MUNICIPAL INVESTMENT TRUST FD INSURED SER 400 DEF ASSET FDS, 487, 1998-10-08

MUNICIPAL INVESTMENT TRUST FD INSURED SER 400 DEF ASSET FDS
487, 1998-10-08

Previous: MACKIE DESIGNS INC, 8-K/A, 1998-10-08

Next: TERA COMPUTER CO WA, 8-K, 1998-10-08

<PAGE>

AS FILED WITH THE SECURITIES AND EXCHANGE COMMISSION ON OCTOBER 8, 1998

REGISTRATION NO. 333-55781

- --------------------------------------------------------------------------------
- --------------------------------------------------------------------------------

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

------------------------------------------

AMENDMENT NO. 1

TO
FORM S-6

------------------------------------------

FOR REGISTRATION UNDER THE SECURITIES ACT
OF 1933 OF SECURITIES OF UNIT INVESTMENT
TRUSTS REGISTERED ON FORM N-8B-2

------------------------------------------

A. EXACT NAME OF TRUST:

MUNICIPAL INVESTMENT TRUST FUND
INSURED SERIES 400
(FORMERLY INSURED SERIES 313)
DEFINED ASSET FUNDS

B. NAME OF DEPOSITOR:

MERRILL LYNCH, PIERCE, FENNER & SMITH INC.

SALOMON SMITH BARNEY INC.

PAINEWEBBER INCORPORATED
DEAN WITTER REYNOLDS INC.

C. COMPLETE ADDRESSES OF DEPOSITORS' PRINCIPAL EXECUTIVE OFFICES:

MERRILL LYNCH, PIERCE,
FENNER &
SMITH INCORPORATED
UNIT INVESTMENT TRUST
DIVISION
P.O. BOX 9051
PRINCETON, NJ 08543-9051 PAINEWEBBER INCORPORATED
1285 AVENUE OF THE
AMERICAS
NEW YORK, NY 10019

SALOMON SMITH BARNEY INC.

388 GREENWICH
STREET--23RD FLOOR
NEW YORK, NY 10013
DEAN WITTER REYNOLDS INC.
TWO WORLD TRADE
CENTER--59TH FLOOR
NEW YORK, NY 10048

D. NAMES AND COMPLETE ADDRESSES OF AGENTS FOR SERVICE:

TERESA KONCICK, ESQ.
P.O. BOX 9051
PRINCETON, NJ 08543-9051 ROBERT E. HOLLEY
1200 HARBOR BLVD.
WEEHAWKEN, NJ 07087

COPIES TO: DOUGLAS LOWE, ESQ.
PIERRE DE SAINT PHALLE, DEAN WITTER REYNOLDS INC.
LAURIE A. HESSLEIN ESQ. TWO WORLD TRADE
388 GREENWICH STREET 450 LEXINGTON AVENUE CENTER--59TH FLOOR
NEW YORK, NY 10013 NEW YORK, NY 10017 NEW YORK, NY 10048

E. TITLE OF SECURITIES BEING REGISTERED:

An indefinite number of Units of Beneficial Interest pursuant to Rule 24f-2
promulgated under the Investment Company Act of 1940, as amended.

F. APPROXIMATE DATE OF PROPOSED SALE TO PUBLIC:

As soon as practicable after the effective date of the Registration Statement.

/ x / Check box if it is proposed that this registration statement will become
effective upon filing on October 8, 1998, pursuant to Rule 487.

- --------------------------------------------------------------------------------
- --------------------------------------------------------------------------------
<PAGE>
DEFINED ASSET FUNDSSM
- --------------------------------------------------------------------------------
- --------------------------------------------------------------------------------

MUNICIPAL INVESTMENT TRUST FUND
INSURED SERIES 400
(A UNIT INVESTMENT TRUST)

O PORTFOLIO OF INSURED LONG TERM MUNICIPAL BONDS
O DESIGNED FOR FEDERALLY TAX-FREE INCOME

O INCOME DISTRIBUTIONS TWICE A YEAR

SPONSORS: -------------------------------------------------
Merrill Lynch, The Securities and Exchange Commission has not
Pierce, Fenner & Smith approved or disapproved these Securities or
Incorporated passed upon the adequacy of this prospectus. Any

Salomon Smith Barney Inc. representation to the contrary is a criminal
PaineWebber Incorporated offense.
Dean Witter Reynolds Inc. Prospectus dated October 8, 1998.

<PAGE>
- --------------------------------------------------------------------------------

Defined Asset FundsSM

DEFINED ASSET FUNDSSM IS AMERICA'S OLDEST AND LARGEST FAMILY OF UNIT INVESTMENT
TRUSTS WITH OVER $115 BILLION SPONSORED IN THE LAST 25 YEARS. OUR FAMILY OF

DEFINED FUNDS HELPS INVESTORS WORK TOWARD THEIR FINANCIAL GOALS WITH A FULL
RANGE OF QUALITY INVESTMENTS, INCLUDING MUNICIPAL, CORPORATE AND GOVERNMENT BOND
PORTFOLIOS, AS WELL AS DOMESTIC AND INTERNATIONAL EQUITY PORTFOLIOS.

DEFINED ASSET FUNDS OFFER A NUMBER OF ADVANTAGES:
O FIXED PORTFOLIO: DEFINED FUNDS FOLLOW A BUY AND HOLD INVESTMENT STRATEGY;
FUNDS ARE NOT MANAGED AND PORTFOLIO CHANGES ARE LIMITED.
O PRESELECTED PORTFOLIOS: WE CHOOSE THE STOCKS AND BONDS IN ADVANCE, SO YOU
KNOW WHAT YOU'RE INVESTING IN.
O PROFESSIONAL RESEARCH: OUR DEDICATED RESEARCH TEAM SEEKS OUT STOCKS OR
BONDS APPROPRIATE FOR A PARTICULAR FUND'S OBJECTIVES.
O ONGOING SUPERVISION: WE MONITOR EACH PORTFOLIO ON AN ONGOING BASIS.
NO MATTER WHAT YOUR INVESTMENT GOALS, TOLERANCE FOR RISK OR TIME HORIZON,
THERE'S PROBABLY A DEFINED ASSET FUND THAT SUITS YOUR INVESTMENT STYLE. YOUR
FINANCIAL PROFESSIONAL CAN HELP YOU SELECT A DEFINED ASSET FUND THAT WORKS BEST
FOR YOUR INVESTMENT PORTFOLIO.

CONTENTS
PAGE
-----------
RISK/RETURN SUMMARY AND PORTFOLIO....................... 3
WHAT YOU CAN EXPECT FROM YOUR INVESTMENT................ 6
INCOME TWICE A YEAR.................................. 6
RETURN FIGURES....................................... 6
RECORDS AND REPORTS.................................. 6
THE RISKS YOU FACE...................................... 7
INTEREST RATE RISK................................... 7
CALL RISK............................................ 7
REDUCED DIVERSIFICATION RISK......................... 7
LIQUIDITY RISK....................................... 7
CONCENTRATION RISK................................... 7
BOND QUALITY RISK.................................... 7
INSURANCE RELATED RISK............................... 7
LITIGATION AND LEGISLATION RISKS..................... 8
SELLING OR EXCHANGING UNITS............................. 8
SPONSORS' SECONDARY MARKET........................... 8
SELLING UNITS TO THE TRUSTEE......................... 8
EXCHANGE OPTION...................................... 9
HOW THE FUND WORKS...................................... 10
PRICING.............................................. 10
EVALUATIONS.......................................... 10
INCOME............................................... 10
EXPENSES............................................. 10
PORTFOLIO CHANGES.................................... 11
FUND TERMINATION..................................... 11
CERTIFICATES......................................... 12
TRUST INDENTURE...................................... 12
LEGAL OPINION........................................ 13
AUDITORS............................................. 13
SPONSORS............................................. 13
TRUSTEE.............................................. 13
UNDERWRITERS' AND SPONSORS' PROFITS.................. 13
PUBLIC DISTRIBUTION.................................. 14
CODE OF ETHICS....................................... 14
YEAR 2000 ISSUES..................................... 14
TAXES................................................... 14

SUPPLEMENTAL INFORMATION................................ 15
FINANCIAL STATEMENTS.................................... 16
REPORT OF INDEPENDENT ACCOUNTANTS.................... 16
STATEMENT OF CONDITION............................... 16

2
<PAGE>
- --------------------------------------------------------------------------------

RISK/RETURN SUMMARY

1. WHAT IS THE FUND'S OBJECTIVE?
The Fund seeks interest income that is exempt from regular
federal income taxes by investing in a fixed portfolio
consisting primarily of insured, 15-to 30-year municipal
revenue bonds.
2. WHAT ARE MUNICIPAL REVENUE BONDS?
Municipal revenue bonds are bonds issued by states,
municipalities and public authorities to finance the cost
of buying, building or improving various projects intended
to generate revenue, such as airports, health care
facilities, housing and municipal electric, water and sewer
utilities. Generally, payments on these bonds depend solely
on the revenues generated by the projects, excise taxes or
state appropriations, and are not backed by the
government's taxing power.
3. WHAT IS THE FUND'S INVESTMENT STRATEGY?
o The Fund plans to hold to maturity 12 insured, long-term
tax-exempt municipal bonds with an aggregate face amount of

$10,000,000, and some short-term bonds reserved to pay the
deferred sales charge. The Fund is a unit investment trust
which means that, unlike a mutual fund, the Fund's
portfolio is not managed.
o The bonds are rated AAA or Aaa by Standard & Poor's,

Moody's or Fitch.
o Most of the bonds cannot be called for several years, and
after that they can be called at a premium declining over
time to par value. Some bonds may be called earlier at par
for extraordinary reasons.
o 100% of the bonds are insured by AAA-rated insurance
companies that guarantee timely payments of principal and
interest on the bonds (but not Fund units or the market
value of the bonds before they mature).

The Portfolio consists of municipal bonds of the following
types:

APPROXIMATE
PORTFOLIO
PERCENTAGE

o Airports/Ports/Highways 10%
o Convention Centers 10%
o General Obligation 1%
o Hospitals/Health Care 38%
o Housing 9%
o Miscellaneous 9%
o Municipal Water/Sewer Utilities 7%
o Special Tax 5%
o State/Local Government
Supported 1%
o State/Local Municipal Electric
Utilities 9%
o Tax Allocation 1%

4. WHAT ARE THE SIGNIFICANT RISKS?
YOU CAN LOSE MONEY BY INVESTING IN THE FUND. THIS CAN
HAPPEN FOR VARIOUS REASONS, INCLUDING:
o Rising interest rates, an issuer's worsening financial
condition or a drop in bond ratings can reduce the price of
your units.

o Because the Fund is concentrated in Hospital/Health Care

bonds, adverse developments in this industry may affect the
value of your units.
o Assuming no changes in interest rates, when you sell your
units, they will generally be worth less than your cost
because your cost included a sales fee.
o The Fund will receive early returns of principal if bonds
are called or sold before they mature. If this happens your
income will decline and you may not be able to reinvest the
money you receive at as high a yield or as long a maturity.

5. IS THIS FUND APPROPRIATE FOR YOU?
Yes, if you want federally tax-free income. You will
benefit from a professionally selected and supervised
portfolio whose risk is reduced by investing in insured
bonds of several different issuers.
The Fund is not appropriate for you if you want a
speculative investment that changes to take advantage of
market movements, if you do not want a tax-advantaged
investment or if you cannot tolerate any risk.

3
<PAGE>
- --------------------------------------------------------------------------------

DEFINED PORTFOLIO

- --------------------------------------------------------------------------------

Insured Series--400

<TABLE><CAPTION>
RATING COST
PORTFOLIO TITLE COUPON MATURITY (1) OF ISSUES (2) TO FUND (3)
- --------------------------------------------------------------------------------------------------------------
AIRPORT/PORTS/HIGHWAYS (10 %):
<S> <C> <C> <C> <C>
1. $1,000,000 City of Manchester, NH, Gen. 4.50% 1/1/28 AAA $ 950,040.00
Airport Rev. Bonds, Ser. 1998 A (MBIA
Ins.)
2. $5,000 State of Ohio Tpke. Rev. Bonds, 3.80 2/15/01 AAA 5,050.35
Ser. 1998 B (Financial Guaranty Ins.) (4)

CONVENTION CENTERS (10 %):

3. $1,000,000 Washington Conv. Ctr. Auth., 4.75 10/1/28 AAA 976,540.00
Washington, DC, Sr. Lien Dedicated Tax
Rev. Bonds, Ser. 1998 (AMBAC Ins.)

GENERAL OBLIGATION BONDS (1 %):

4. $70,000 County of Pike, Commonwealth of 3.80 10/1/99 Aaa(m) 70,538.30
Pennsylvania, Gen. Oblig. Bonds, Ser. 1998
(AMBAC Ins.) (4)

HOSPITALS/HEALTH CARE (38 %):

5. $55,000 California Statewide Cmntys. Dev. 5.25 8/15/00 AAA 56,962.40
Auth., Sutter Hlth. Oblig. Grp. (AMBAC
Ins.) (4)
6. $1,000,000 Illinois Hlth. Fac. Auth., Rev. 5.00 7/1/24 AAA 1,004,040.00
Bonds (Loyola Univ. Hlth. Sys.), Ser. 1997
A (MBIA Ins.)
7. $1,000,000 Iowa Fin. Auth., Hosp. Facs. 5.125 1/1/28 AAA 1,015,350.00
Rev. Bonds (Iowa Hlth. Sys.), Ser. 1998 A
(MBIA Ins.)
8. $1,000,000 Michigan State Hosp. Fin. 5.00 8/15/31 AAA 1,000,000.00
Auth., Rev. and Rfdg. Bonds (Oakwood
Oblig. Grp.), Ser. 1998 A (FSA Ins.)
9. $820,000 Hospital Auth. of St. Joseph 4.625 8/15/28 AAA 791,004.80
Cnty., IN, Hlth. Sys. Bonds (Memorial
Hlth. Sys.), Ser. 1998 A (MBIA Ins.)

HOUSING (9 %):

10. $1,000,000 Housing Auth. of the City of 5.20 11/1/27 Aaa(m) 1,007,750.00
Bellingham, WA, Hsg. Rfdg. Rev. Bonds
(Pacific Rim and Cascade Meadows
Projs.), Ser. 1998 (MBIA Ins.)
</TABLE>

- ------------------------------------
(1) Approximately 98% of the bonds are callable 2006-2008.
(2) All ratings are by Standard & Poor's Ratings Group unless followed by
'(m)', which indicates a Moody's Investors Service rating or by '(f)',
which indicates a Fitch IBCA rating. An AAA rating indicates highest
quality bonds with a very strong capacity to pay interest and repay
principal.

------------------------------------

PLEASE NOTE THAT IF THIS PROSPECTUS IS USED AS A PRELIMINARY
PROSPECTUS
FOR A FUTURE FUND IN THIS SERIES, THE PORTFOLIO WILL CONTAIN
DIFFERENT
BONDS FROM THOSE DESCRIBED ABOVE.
(Continued on next page)

<PAGE>
- --------------------------------------------------------------------------------
DEFINED PORTFOLIO
- --------------------------------------------------------------------------------

Insured Series--400 (Continued)

<TABLE><CAPTION>
RATING COST
PORTFOLIO TITLE COUPON MATURITY (1) OF ISSUES (2) TO FUND (3)
- --------------------------------------------------------------------------------------------------------------
MISCELLANEOUS (9 %):
<S> <C> <C> <C> <C>
11. $1,000,000 Central Falls Detention Fac. 5.00% 1/15/23 AAA $ 1,004,200.00
Corp., RI, Detention Fac. Rev. Rfdg.
Bonds (The Donald W. Wyatt Detention
Fac.), Ser. 1998 A (FSA Ins.)

MUNICIPAL WATER/SEWER UTILITIES (7 %):

12. $200,000 East Bay Mun. Util. Dist. 4.75 6/1/34 AAA 198,288.00
(Alameda and Contra Costa Cntys., CA),
Wtr. Sys. Sub. Rev. Bonds, Ser. 1998
(MBIA Ins.)
13. $500,000 Mississippi Dev. Bank (City of 5.00 7/1/23 AAA 501,870.00
D'Iberville), Spec. Oblig. Bonds
(Combined Wtr. and Swr. Sys. Rev. Rfdg.
Proj.), Ser. 1998 (AMBAC Ins.)
14. $15,000 Middlesex Cnty. Util. Auth., Swr. 6.20 3/15/01 AAA 15,992.70
Rev. Bonds, Ser. 1991 A (Financial
Guaranty Ins.)(4)

SPECIAL TAX (5 %):

15. $480,000 Marion Cnty. Conv. and Rec. 5.00% 6/1/27 AAA 481,934.40
Facs. Auth., IN, Excise Taxes Lease
Rental Rev. Sr. Bonds, Ser. 1997 A (MBIA
Ins.)

STATE/LOCAL GOVERNMENT SUPPORTED (1 %):

16. $15,000 Casino Reinvestment Dev. Auth., 5.00 10/1/99 AAA 15,288.45
NJ, Parking Fee Rev. Bonds, Ser. 1997 A
(FSA Ins.)(4)

STATE/LOCAL MUNICIPAL ELECTRIC UTILITIES (9 %):

17. $1,000,000 Intermountain Pwr. Agy., UT, 5.00 7/1/21 AAA 1,007,590.00
Pwr. Supply Rev. Rfdg. Bonds, Ser. 1996 D
(FSA Ins.)

TAX ALLOCATION (1 %):

18. $20,000 Miami Beach Redev. Agy., FL, Tax 3.85 12/1/00 AAA 20,246.60
Increment Rev. Bonds (City Ctr./Historic
Conv. Village), Ser. 1998 B (MBIA
Ins.)(4)
--------------------
$ 10,122,686.00
--------------------
--------------------
</TABLE>

- ------------------------------------
(3) Approximately 60% of the bonds were deposited at a premium, 10% at par and
30% at a discount from par. Sponsors' profit on deposit was $136,125.65.

(4) The interest and principal on these bonds will be used to pay the deferred
sales charge obligations of the investors, and these amounts are not
included in the calculation of Estimated Current and Long Term Returns.
------------------------------------

PLEASE NOTE THAT IF THIS PROSPECTUS IS USED AS A PRELIMINARY
PROSPECTUS
FOR A FUTURE FUND IN THIS SERIES, THE PORTFOLIO WILL CONTAIN
DIFFERENT
BONDS FROM THOSE DESCRIBED ABOVE.

<PAGE>

DEFINING YOUR INCOME AND
ESTIMATING YOUR RETURN

WHAT YOU MAY EXPECT (RECORD DAY: 10th day of
each April and October)
First payment per 1,000 units (4/25/99) $ 24.20
Regular Semi-Annual Income per 1,000 units
(each April and October beginning 10/25/99): $ 23.94
Annual Income per 1,000 units: $ 47.88
These figures are estimates on the business day before the
initial date of deposit; actual payments may vary.

Estimated Current Return 4.67%
Estimated Long Term Return 4.64%
These returns will vary (see page 6)

6. WHAT ARE THE FUND'S FEES AND EXPENSES?
This table shows the costs and expenses you may pay,
directly or indirectly, when you invest in the Fund.

INVESTOR FEES
2.90%
Maximum Sales Fee (Load) on new purchases
(as a percentage of $1,000 invested)

You will pay an up-front sales fee of 1.00%, as well as a
total deferred sales fee of $19.00 ($2.38 per 1,000 units
quarterly in the first year and $2.37 per 1,000 units
quarterly in the second year). Employees of some of the
Sponsors and their affiliates may be charged a reduced
sales fee of no less than $5.00 per 1,000 Units.
The maximum sales fee is reduced if you invest at least
$100,000, as follows:

YOUR MAXIMUM
SALES FEE
IF YOU INVEST: WILL BE:
----------------------------------- -----------------

Less than $100,000 2.90%

$100,000 to $249,999 2.65%
$250,000 to $499,999 2.40%
$500,000 to $999,999 2.15%
$1,000,000 and over 1.90%
Maximum Exchange Fee 1.90%

ESTIMATED ANNUAL FUND OPERATING EXPENSES

AS A % OF AMOUNT
$1,000 PER 1,000
INVESTED UNITS
---------- -----------

.062% $ 0.63
Trustee's Fee
.035% $ 0.36
Portfolio Supervision,
Bookkeeping and
Administrative Fees
.013% $ 0.13
Evaluator's Fee
.021% $ 0.21
Other Operating Expenses
---------- -----------
.131% $ 1.33
TOTAL

AMOUNT
PER 1,000
UNITS
---------------------
$ 2.00
ORGANIZATIONAL COSTS (deducted from
Fund assets at the close of the
initial offering period)

EXAMPLE
This example may help you compare the cost of investing in
the Fund to the cost of investing in other funds.
The example assumes that you invest $10,000 in the Fund for
the periods indicated and sell all your units at the end of
those periods. The example also assumes a 5% return on your
investment each year and that the Fund's operating expenses
stay the same. Although your actual costs may be higher or
lower, based on these assumptions your costs would be:

1 Year 3 Years 5 Years 10 Years
$134 $163 $194 $287

You will pay the following expenses if you do not sell
your units:

1 Year 3 Years 5 Years 10 Years
$125 $163 $194 $287

7. HOW HAVE SIMILAR FUNDS PERFORMED IN THE PAST?
In the following chart we show past performance of prior

municipal Insured Series, which had the same investment
objectives, strategies and types of bonds as this Fund.
These prior Series differed in that they charged a higher
sales fee. These prior Insured Series were offered between
January 1, 1988 and October 31, 1996 and were outstanding

on June 30, 1998. OF COURSE, PAST PERFORMANCE OF PRIOR
SERIES IS NO GUARANTEE OF FUTURE RESULTS OF THIS FUND.
AVERAGE ANNUAL COMPOUND TOTAL RETURNS
FOR PRIOR SERIES
Reflecting all expenses. For periods ended 6/30/98.

WITH SALES FEE NO SALES FEE
1 YEAR 5 YEARS 1 YEAR 5 YEARS

- ---------------------------------------------------------------
High 5.98% 5.51% 12.07% 6.55%
Average 4.11 4.45 7.58 5.50
Low 0.22 3.71 2.57 4.56
- ---------------------------------------------------------------

Average
Sales fee 3.36% 5.20%

- ----------------------------------------------------------------

Note: All returns represent changes in unit price with distributions reinvested
into the Municipal Fund Investment Accumulation Program.

8. IS THE FUND MANAGED?
Unlike a mutual fund, the Fund is not managed and bonds are
not sold because of market changes. Rather, experienced

4
<PAGE>

Defined Asset Funds financial analysts regularly review the
bonds in the Fund. The Fund may sell a bond if certain
adverse credit or other conditions exist.
9. HOW DO I BUY UNITS?
You can buy units from any of the Sponsors and other
broker-dealers. The Sponsors are listed later in this
prospectus. Some banks may offer units for sale through
special arrangements with the Sponsors, although certain
legal restrictions may apply.

The minimum investment is $250.
UNIT PRICE PER 1,000 UNITS $1,024.31
(as of October 7, 1998)

Unit price is based on the net asset value of the Fund plus
the up-front sales fee. An amount equal to any principal
cash, as well as net accrued but undistributed interest on
the unit, is added to the unit price. Unit price also
includes the estimated organization costs shown on the
previous page. An independent evaluator prices the bonds at
3:30 p.m. Eastern time every business day. Unit price
changes every day with changes in the prices of the bonds in
the Fund.
UNIT PAR VALUE $1.00
Unit par value means the total amount of money you should
generally receive on each unit by the termination of the
Fund (other than interest and premium on the bonds). This
total amount assumes that all bonds in the Fund are either
paid at maturity or called by the issuer at par or are sold
by the Fund at par. If you sell your units before the Fund
terminates, you may receive more or less than the unit par
value.
10. HOW DO I SELL UNITS?
You may sell your units at any time to any Sponsor or the
Trustee for the net asset

value determined at the close of business
on the date of sale, less any remaining
deferred sales fee. You will not pay any other fee when you
sell your units.
11. HOW ARE DISTRIBUTIONS MADE AND TAXED?
The Fund pays income twice a year. In the opinion of bond
counsel when each bond was issued, interest on the bonds in
this Fund is generally 100% exempt from regular federal
income tax. A portion of the income may also be exempt from
state and local personal income taxes, depending on where
you live.
You will also receive principal payments if bonds are sold
or called or mature, when the cash available is more than
$10.00 per 1,000 units. You will be subject to tax on any
gain realized by the Fund on the disposition of bonds.
12. WHAT OTHER SERVICES ARE AVAILABLE?
REINVESTMENT
You will receive your income in cash unless you choose to
compound your income by reinvesting at no sales fee in the
Municipal Fund Investment Accumulation Program, Inc. This
Program is an open-end mutual fund with a comparable
investment objective except that those bonds will generally
not be insured. Income from this Program will generally be
subject to state and local income taxes. For more complete
information about the Program, including charges and fees,
ask the Trustee for the Program's prospectus. Read it
carefully before you invest. The Trustee must receive your
written election to reinvest at least 10 days before the
record day of an income payment.
EXCHANGE PRIVILEGES
You may exchange units of this Fund for units of certain
other Defined Asset Funds. You may also exchange into this
Fund from certain other funds. We charge a reduced sales fee
on exchanges.

- --------------------------------------------------------------------------------
TAX-FREE VS. TAXABLE INCOME: A COMPARISON OF TAXABLE AND TAX-FREE YIELDS

EFFECTIVE
TAXABLE INCOME 1998* % TAX TAX-FREE YIELD OF
SINGLE RETURN JOINT RETURN BRACKET 3% 3.5% 4% 4.5% 5% 5.5% 6% 6.5%
IS EQUIVALENT TO A TAXABLE YIELD OF
- ----------------------------------------------------------------------------------------------------------
<S> <C> <C> <C> <C> <C> <C> <C> <C> <C> <C>
$ 0- 25,350 $ 0- 42,350 15.00 3.53 4.12 4.71 5.29 5.88 6.47 7.06 7.65
- ----------------------------------------------------------------------------------------------------------
$ 25,351- 61,400 $ 42,351-102,300 28.00 4.17 4.86 5.56 6.25 6.94 7.64 8.33 9.03
- ----------------------------------------------------------------------------------------------------------
$ 61,401-128,100 $102,301-155,950 31.00 4.35 5.07 5.80 6.52 7.25 7.97 8.70 9.42
- ----------------------------------------------------------------------------------------------------------
$128,101-278,450 $155,951-278,450 36.00 4.69 5.47 6.25 7.03 7.81 8.59 9.38 10.16
- ----------------------------------------------------------------------------------------------------------
OVER $278,450 OVER $278,450 39.60 4.97 5.79 6.62 7.45 8.28 9.11 9.93 10.76
- --------------------------------------------------------------------------------------------------
</TABLE>

To compare the yield of a taxable security with the yield of a tax-free
security, find your taxable income and read across. The table incorporates 1998
federal income tax rates and assumes that all income would otherwise be taxed at
the investor's highest tax rate. Yield figures are for example only.

*Based upon net amount subject to federal income tax after deductions and
exemptions. This table does not reflect the possible effect of other tax
factors, such as alternative minimum tax, personal exemptions, the phase out of
exemptions, itemized deductions, the possible partial disallowance of deductions
or state or local taxation. Consequently, you should consult your own tax
advisers in this regard.

5
<PAGE>
WHAT YOU CAN EXPECT FROM YOUR INVESTMENT

INCOME TWICE A YEAR

The Fund will pay you regular income twice a year. Your income may vary because
of:
o elimination of one or more bonds from the Fund's portfolio because of
calls, redemptions or sales;
o a change in the Fund's expenses; or
o the failure by a bond's issuer to pay interest.

Changes in interest rates generally will not affect your income because the
portfolio is fixed.

Along with your income, you will receive your share of any available bond
principal.

RETURN FIGURES

We cannot predict your actual return, which will vary with unit price, how long
you hold your investment and changes in the portfolio, interest income and
expenses.

Estimated Current Return equals the estimated annual cash to be received from
the bonds in the Fund less estimated annual Fund expenses, divided by the Unit
Price (including the maximum sales fee):

Estimated Annual Estimated
Interest Income - Annual Expenses
- -------------------------------------------------
Unit Price

Estimated Long Term Return is a measure of the estimated return over the
estimated life of the Fund. Unlike Estimated Current Return, Estimated Long Term
Return reflects maturities, discounts and premiums of the bonds in the Fund. It
is an average of the yields to maturity (or in certain cases, to an earlier call
date) of the individual bonds in the portfolio, adjusted to reflect the Fund's
maximum sales fee and estimated expenses. We calculate the average yield for the
portfolio by weighting each bond's yield by its market value and the time
remaining to the call or maturity date.

Yields on individual bonds depend on many factors including general conditions
of the bond markets, the size of a particular offering and the maturity and
quality rating of the particular issues. Yields can vary among bonds with
similar maturities, coupons and ratings.

These return quotations are designed to be comparative rather than predictive.

RECORDS AND REPORTS

You will receive:
o a statement of income payments twice a year;
o a notice from the Trustee when new bonds are deposited in exchange or
substitution for bonds originally deposited;
o an annual report on Fund activity; and
o annual tax information. This will also be sent to the IRS. You must report the
amount of tax-exempt interest received during the year.

You may request:
o copies of bond evaluations to enable you to comply with federal and state tax
reporting requirements; and
o audited financial statements of the Fund.

You may inspect records of Fund transactions at the Trustee's office during
regular business hours.

6
<PAGE>
THE RISKS YOU FACE

INTEREST RATE RISK

Investing involves risks, including the risk that your investment will decline
in value if interest rates rise. Generally, bonds with longer maturities will
change in value more than bonds with shorter maturities. Bonds in the Fund are
more likely to be called when interest rates decline. This would result in early
returns of principal to you and may result in early termination of the Fund. Of
course, we cannot predict how interest rates may change.

CALL RISK

Many bonds can be prepaid or 'called' by the issuer before their stated
maturity.

For example, an issuer might call its bonds if it no longer needs the money for
the original purpose or, during periods of falling interest rates, if the
issuer's bonds have a coupon higher than current market rates. If the bonds are
called, your income will decline and you may not be able to reinvest the money
you receive at as high a yield or as long a maturity. An early call at par of a
premium bond will reduce your return.

REDUCED DIVERSIFICATION RISK

If many investors sell their units, the Fund will have to sell bonds. This could
reduce the diversification of your investment and increase your share of Fund
expenses.

LIQUIDITY RISK

The bonds will generally trade in the over-the-counter market. We cannot assure
you that a liquid trading market will exist, especially since current law may
restrict the Fund from selling bonds to any Sponsor. The value of the bonds, and
of your investment, may be reduced if trading in bonds is limited or absent.

CONCENTRATION RISK

When a certain type of bond makes up 25% or more of the portfolio, the Fund is
said to be 'concentrated' in that bond type, which makes the Fund less
diversified.

Here is what you should know about the Fund's concentration in hospital and
health care bonds.
o payment for these bonds depends on revenues from private third-party payors
and government programs, including Medicare and Medicaid, which have
generally undertaken cost containment measures to limit payments to health
care providers;
o hospitals face competition resulting from hospital mergers and
affiliations;
o hospitals need to reduce costs as HMOs increase market penetration and
hospital supply and drug companies raise prices; and
o hospitals and health care providers are subject to various legal claims by
patients and others and are adversely affected by increasing costs of
insurance.

Changes to the portfolio from bond redemptions, maturities and sales may affect
the Fund's concentration over time.

BOND QUALITY RISK

A reduction in a bond's rating may decrease its value and, indirectly, the value
of your investment in the Fund.

INSURANCE RELATED RISK

The bonds are backed by insurance companies (as shown under Defined Portfolio).
Insurance policies generally make payments only according to a bond's original
payment schedule and do not make early payments when a bond defaults or becomes
taxable.

7
<PAGE>
Although the federal government does not regulate the insurance business,
various state laws and federal initiatives and tax law changes could
significantly affect the insurance business. The claims-paying ability of the
insurance companies is generally rated AAA by Standard & Poor's or another
nationally recognized rating organization. The insurance company ratings are
subject to change at any time at the discretion of the rating agencies.

LITIGATION AND LEGISLATION RISKS

We do not know of any pending litigation that might have a material adverse
effect upon the Fund.

Future tax legislation could affect the value of the portfolio by:
o limiting real property taxes,
o reducing tax rates,
o imposing a flat or other form of tax, or
o exempting investment income from tax.

SELLING OR EXCHANGING UNITS

You can sell your units at any time for a price based on net asset value. Your
net asset value is calculated each business day by:
o adding the value of the bonds, net accrued interest, cash and any other
Fund assets;
o subtracting accrued but unpaid Fund expenses, unreimbursed Trustee
advances, cash held to buy back units or for distribution to investors and
any other Fund liabilities; and
o dividing the result by the number of outstanding units.

Your net asset value when you sell may be more or less than your cost because of
sales fees, market movements and changes in the portfolio.

As of the close of the initial offering period, the price you receive will be
reduced to reflect estimated organization costs.

If you sell your units before the final deferred sales fee installment, the
amount of any remaining installments will be deducted from your proceeds.

SPONSORS' SECONDARY MARKET

While we are not obligated to do so, we will buy back units at net asset value
without any other fee or charge other than any remaining deferred sales charge.
We may resell the units to other buyers or to the Trustee. You should consult
your financial professional for current market prices to determine if other
broker-dealers or banks are offering higher prices.

We have maintained a secondary market continuously for over 25 years, but we
could discontinue it without prior notice for any business reason.

SELLING UNITS TO THE TRUSTEE

Regardless of whether we maintain a secondary market, you can sell your units to
the Trustee at any time by sending the Trustee a letter (with any outstanding
certificates if you hold Unit certificates). You must properly endorse your
certificates (or execute a written transfer instrument with signatures
guaranteed by an eligible institution). Sometimes, additional documents are
needed such as a trust document, certificate of corporate authority, certificate
of death or appointment as executor, administrator or guardian.

Within seven days after your request and the necessary documents are received,
the Trustee will mail a check to you. Contact the Trustee for additional
information.

8
<PAGE>
As long as we are maintaining a secondary market, the Trustee will sell your
units to us at a price based on net asset value. If there is no secondary
market, the Trustee may sell your units in the over-the-counter market for a
higher price, but it is not obligated to do so. In that case, you will receive
the net proceeds of the sale.

If the Fund does not have cash available to pay you for units you are selling,
the agent for the Sponsors will select bonds to be sold. Bonds will be selected
based on market and credit factors. These sales could be made at times when the
bonds would not otherwise be sold and may result in your receiving less than the
unit par value and also reduce the size and diversity of the Fund.

If you acquire 25% or more of the outstanding units of the Fund and you sell
units with a value exceeding $250,000, the Trustee may choose to pay you 'in
kind' by distributing bonds and cash with a total value equal to the price of
those units. The Trustee will try to distribute bonds in the portfolio pro rata,
but it reserves the right to distribute only one or a few bonds. The Trustee
will act as your agent in an in kind distribution and will either hold the bonds
for your account or sell them as you instruct. You must pay any transaction
costs as well as transfer and ongoing custodial fees on sales of bonds
distributed in kind.

There could be a delay in paying you for your units:
o if the New York Stock Exchange is closed (other than customary weekend and
holiday closings);
o if the SEC determines that trading on the New York Stock Exchange is
restricted or that an emergency exists making sale or evaluation of the
bonds not reasonably practicable; and
o for any other period permitted by SEC order.

EXCHANGE OPTION

You may exchange units of certain Defined Asset Funds for units of this Fund at
a maximum exchange fee of 1.90%. You may exchange units of this Fund for units
of certain other funds at a reduced sales fee if your investment goals change.
To exchange units, you should talk to your financial professional about what
funds are exchangeable, suitable and currently available.

Normally, an exchange is taxable and you must recognize any gain or loss on the
exchange. However, the IRS may try to disallow a loss if the portfolios of the
two funds are not materially different; you should consult your own tax adviser.

We may amend or terminate this exchange option at any time without notice.

9
<PAGE>
HOW THE FUND WORKS

PRICING

The price of a unit includes interest accrued on the bonds, less expenses, from
the initial date of deposit up to, but not including, the settlement date, which
is usually three business days after the purchase date of the unit.

Bonds also carry accrued but unpaid interest up to the initial date of deposit.
To avoid having you pay this additional accrued interest (which earns no return)
when you buy, the Trustee advances this amount to the Sponsors. The Trustee
recovers this advance from interest received on the bonds.

In addition, a portion of the price of a unit consists of cash to pay all or
some of the costs of organizing the Fund including:
o cost of initial preparation of legal documents;
o federal and state registration fees;
o initial fees and expenses of the Trustee;
o initial audit; and
o legal expenses and other out-of-pocket expenses.

EVALUATIONS

An independent Evaluator values the bonds on each business day (excluding
Saturdays, Sundays and the following holidays as observed by the New York Stock
Exchange: New Year's Day, Presidents' Day, Martin Luther King, Jr. Day, Good
Friday, Memorial Day, Independence Day, Labor Day, Thanksgiving and Christmas).
Bond values are based on current bid or offer prices for the bonds or comparable
bonds. In the past, the difference between bid and offer prices of publicly
offered tax-exempt bonds has ranged from 0.5% of face amount on actively traded
issues to 3.5% on inactively traded issues; the difference has averaged between
1 and 2%.

INCOME

Interest on any bonds purchased on a when-issued basis or for a delayed delivery
does not begin to accrue until the bonds are delivered to the Fund. The Trustee
may reduce its fee to provide you with tax-exempt income for this non-accrual
period. If a bond is not delivered on time and the Trustee's annual fee and
expenses do not cover the additional accrued interest, we will treat the
contract to buy the bond as failed.

The Trustee credits interest to an Income Account and other receipts to a
Capital Account. The Trustee may establish a Reserve Account by withdrawing from
these accounts amounts it considers appropriate to pay any material liability.
These accounts do not bear interest.

EXPENSES

The Trustee is paid monthly. It also benefits when it holds cash for the Fund in
non-interest bearing accounts. The Trustee may also receive additional amounts:
o to reimburse the Trustee for the Fund's operating expenses;
o for extraordinary services and costs of indemnifying the Trustee and the
Sponsors;
o costs of actions taken to protect the Fund and other legal fees and
expenses;
o expenses for keeping the Fund's registration statement current; and
o Fund termination expenses and any governmental charges.

10
<PAGE>
The Sponsors are currently reimbursed up to 45 cents per $1,000 face amount
annually for providing portfolio supervisory, bookkeeping and administrative
services and for any other expenses properly chargeable to the Fund. While this
fee may exceed the amount of these costs and expenses attributable to this Fund,
the total of these fees for all Series of Defined Asset Funds will not exceed
the aggregate amount attributable to all of these Series for any calendar year.
The Fund also pays the Evaluator's fees.

The Trustee's, Sponsors' and Evaluator's fees may be adjusted for inflation
without investors' approval.

Quarterly deferred sales fees you owe are paid with interest and principal from

certain bonds. If these amounts are not enough, the rest will be paid out of
distributions to you from the Fund's Capital and Income Accounts.

The Sponsors will pay advertising and selling expenses at no charge to the Fund.
If Fund expenses exceed initial estimates, the Fund will owe the excess. The
Trustee has a lien on Fund assets to secure reimbursement of Fund expenses and
may sell bonds if cash is not available.

PORTFOLIO CHANGES

The Sponsors and Trustee are not liable for any default or defect in a bond; if
a contract to buy any bond fails in the first 90 days of the Fund, we generally
will deposit a replacement tax-exempt bond with a similar yield, maturity,
rating and price.

Unlike a mutual fund, the portfolio is designed to remain intact and we may keep
bonds in the portfolio even if their credit quality declines or other adverse
financial circumstances occur. However, we may sell a bond in certain cases if
we believe that certain adverse credit conditions exist or if a bond becomes
taxable.

If we maintain a secondary market in units but are unable to sell the units that
we buy in the secondary market, we will redeem units, which will affect the size
and composition of the portfolio. Units offered in the secondary market may not
represent the same face amount of bonds that they did originally.

We decide whether or not to offer units for sale that we acquire in the
secondary market after reviewing:
o diversity of the portfolio;
o size of the Fund relative to its original size;
o ratio of Fund expenses to income;
o current and long-term returns;
o degree to which units may be selling at a premium over par; and
o cost of maintaining a current prospectus.

FUND TERMINATION

The Fund will terminate following the stated maturity or sale of the last bond
in the portfolio. The Fund may also terminate earlier with the consent of
investors holding 51% of the units or if total assets of the Fund have fallen
below 40% of the face amount of bonds deposited. We will decide whether to
terminate the Fund early based on the same factors used in deciding whether or
not to offer units in the secondary market.

When the Fund is about to terminate you will receive a notice, and you will be
unable to sell your units after that time. On or shortly before termination, we
will sell any remaining bonds, and you will receive your final distribution.

11
<PAGE>
Any bond that cannot be sold at a reasonable price may continue to be held by
the Trustee in a liquidating trust pending its final sale.

You will pay your share of the expenses associated with termination, including
brokerage costs in selling bonds. This may reduce the amount you receive as your
final distribution.

CERTIFICATES

Certificates for units are issued on request. You may transfer certificates by
complying with the requirements for redeeming certificates, described above. You
can replace lost or mutilated certificates by delivering satisfactory indemnity
and paying the associated costs.

TRUST INDENTURE

The Fund is a 'unit investment trust' governed by a Trust Indenture, a contract
among the Sponsors, the Trustee and the Evaluator, which sets forth their duties
and obligations and your rights. A copy of the Indenture is available to you on
request to the Trustee. The following summarizes certain provisions of the
Indenture.

The Sponsors and the Trustee may amend the Indenture without your consent:
o to cure ambiguities;
o to correct or supplement any defective or inconsistent provision;
o to make any amendment required by any governmental agency; or
o to make other changes determined not to be materially adverse to your best
interest (as determined by the Sponsors).
Investors holding 51% of the units may amend the Indenture. Every investor must
consent to any amendment that changes the 51% requirement. No amendment may
reduce your interest in the Fund without your written consent.

The Trustee may resign by notifying the Sponsors. The Sponsors may remove the
Trustee without your consent if:
o it fails to perform its duties and the Sponsors determine that its
replacement is in your best interest; or
o it becomes incapable of acting or bankrupt or its affairs are taken over by
public authorities.
Investors holding 51% of the units may remove the Trustee. The Evaluator may
resign or be removed by the Sponsors and the Trustee without the consent of
investors. The resignation or removal of either becomes effective when a
successor accepts appointment. The Sponsors will try to appoint a successor
promptly; however, if no successor has accepted within 30 days after notice of
resignation, the resigning Trustee or Evaluator may petition a court to appoint
a successor.

Any Sponsor may resign as long as one Sponsor with a net worth of $2 million
remains and agrees to the resignation. The remaining Sponsors and the Trustee
may appoint a replacement. If there is only one Sponsor and it fails to perform
its duties or becomes bankrupt the Trustee may:
o remove it and appoint a replacement Sponsor;
o liquidate the Fund; or
o continue to act as Trustee without a Sponsor.

Merrill Lynch, Pierce, Fenner & Smith Incorporated acts as agent for the
Sponsors.

12
<PAGE>
The Trust Indenture contains customary provisions limiting the liability of the
Trustee, the Sponsors and the Evaluator.
LEGAL OPINION
Davis Polk & Wardwell, 450 Lexington Avenue, New York, New York 10017, as
special counsel for the Sponsors, has given an opinion that the units are
validly issued.

AUDITORS

Deloitte & Touche LLP, 2 World Financial Center, New York, New York 10281,
independent accountants, audited the Statement of Condition included in this
prospectus.

SPONSORS

The Sponsors and their underwriting percentages are:

MERRILL LYNCH, PIERCE, FENNER & SMITH INCORPORATED (a wholly-owned subsidiary of
Merrill Lynch & Co., Inc.)
P.O. Box 9051,

Princeton, NJ 08543-9051 60.00%

SALOMON SMITH BARNEY INC.
(an indirectly wholly-owned subsidiary of
The Travelers Inc.)
388 Greenwich Street--23rd Floor,
New York, NY 10013 15.00%

DEAN WITTER REYNOLDS INC. (a principal operating subsidiary of Morgan Stanley
Dean Witter & Co.)
Two World Trade Center--59th Floor,
New York, NY 10048 5.00%
PAINEWEBBER INCORPORATED (a wholly-owned subsidiary of PaineWebber Group Inc.)
1285 Avenue of the Americas,
New York, NY 10019 20.00%

100.00%

Each Sponsor is a Delaware corporation and it, or its predecessor, has acted as
sponsor to many unit investment trusts. As a registered broker-dealer each
Sponsor buys and sells securities (including investment company shares) for
others (including investment companies) and participates as an underwriter in
various selling groups.

TRUSTEE

The Bank of New York, 101 Barclay Street-- 17 W, New York, New York 10268, is
the Trustee. It is supervised by the Federal Deposit Insurance Corporation, the
Board of Governors of the Federal Reserve System and New York State banking
authorities.

UNDERWRITERS' AND SPONSORS' PROFITS

Underwriters receive sales charges when they sell units. Sponsors also realize a
profit or loss on deposit of the bonds shown under Defined Portfolio. Any cash
made available by you to the Sponsors before the settlement date for those units
may be used in the Sponsors' businesses to the extent permitted by federal law
and may benefit the Sponsors.

A Sponsor or Underwriter may realize profits or sustain losses on bonds in the
Fund which were acquired from underwriting syndicates of which it was a member.

We bought approximately 20% of the bonds in the portfolio from one or more of

the Sponsors (as sole underwriter, managing underwriter or member of an
underwriting syndicate).

13
<PAGE>
During the initial offering period, the Sponsors also may realize profits or
sustain losses on units they hold. In maintaining a secondary market, the
Sponsors will also realize profits or sustain losses in the amount of any
difference between the prices at which they buy units and the prices at which
they resell or redeem them.

PUBLIC DISTRIBUTION

During the initial offering period, units will be distributed to the public by
the Sponsors and dealers who are members of the National Association of
Securities Dealers, Inc. This period is 30 days or less if all units are sold.
The Sponsors may extend the initial period up to 120 days.

The Sponsors do not intend to qualify units for sale in any foreign countries.
This prospectus does not constitute an offer to sell units in any country where
units cannot lawfully be sold.

In the initial offering period, the concession to dealers will be $21 per 1,000
units. We may change the concession at any time. Dealers may resell units to
other dealers with a concession not in excess of the original concession to
dealers.

CODE OF ETHICS

Merrill Lynch, as agent for the Sponsors, has adopted a code of ethics requiring
preclearance and reporting of personal securities transactions by its employees
with access to information on portfolio transactions. The goal of the code is to
prevent fraud, deception or misconduct against the Fund and to provide
reasonable standards of conduct.

YEAR 2000 ISSUES

Many computer systems were designed in such a way that they may be unable to
distinguish between the year 2000 and the year 1900 (commonly known as the 'Year
2000 Problem'). We do not expect that the computer system changes necessary to
prepare for the Year 2000 will cause any major operational difficulties for the
Fund.

TAXES

The following summary describes some of the important income tax consequences of
holding units. It assumes that you are not a dealer, financial institution,
insurance company or other investor with special circumstances. You should
consult your own tax adviser about your particular circumstances.

At the date of issue of each bond, counsel for the issuer delivered an opinion
to the effect that interest on the bond is exempt from regular federal income
tax. However, interest may be subject to state and local taxes and federal
alternative minimum tax. Neither we nor our counsel have reviewed the issuance
of the bonds, related proceedings or the basis for the opinions of counsel for
the issuers. We cannot assure you that the issuer (or other users) have complied
or will comply with any requirements necessary for a bond to be tax-exempt. If
any of the bonds were determined not to be tax-exempt, you could be required to
pay income tax for current and prior years, and if the Fund were to sell the
bond, it might have to sell it at a substantial discount.

In the opinion of our counsel, under existing law:

GENERAL TREATMENT OF THE FUND AND YOUR INVESTMENT

The Fund will not be taxed as a corporation for federal income tax purposes, and
you will

14
<PAGE>
be considered to own directly your share of each bond in the Fund.

INCOME OR LOSS UPON DISPOSITION

When all or part of your share of a bond is disposed of (for example, when the
Fund sells, exchanges or redeems a bond or when you sell or exchange your
units), you will generally recognize capital gain or loss. Your gain, however,
will generally be ordinary income to the extent of any accrued 'market
discount'. Generally you will have market discount to the extent that your basis
in a bond when you purchase a unit is less than its stated redemption price at
maturity (or, if it is an original issue discount bond, the issue price
increased by original issue discount that has accrued on the bond before your
purchase). You should consult your tax adviser in this regard.

If your net long-term capital gains exceed your net short-term capital losses,
the excess may be subject to tax at a lower rate than ordinary income. Any
capital gain from the Fund will be long-term if you are considered to have held
your investment on each bond for more than one year and short-term if you held
it for one year or less. If you are an individual and sell your units after
holding them for more than 12 months, you may be entitled to a 20% maximum
federal tax rate on any resulting gains. Consult your tax adviser in this
regard. Because the deductibility of capital losses is subject to limitations,
you may not be able to deduct all of your capital losses.

YOUR BASIS IN THE BONDS

Your aggregate basis in the bonds will be equal to the cost of your units,
including any sales charges and the organizational expenses you pay, adjusted to
reflect any accruals of 'original issue discount,' 'acquisition premium' and
'bond premium'. You should consult your tax adviser in this regard.

EXPENSES

If you are not a corporate investor, you will not be entitled to a deduction for
your share of fees and expenses of the Fund. Also, if you borrowed money in
order to purchase or carry your units, you will not be able to deduct the
interest on this borrowing for federal income tax purposes. The IRS may treat
your purchase of units as made with borrowed money even if the money is not
directly traceable to the purchase of units.

STATE AND LOCAL TAXES

Under the income tax laws of the State and City of New York, the Fund will not
be taxed as a corporation. If you are a New York taxpayer, your income from the
Fund will not be tax-exempt in New York except to the extent that the income is
earned on bonds that are tax-exempt for New York purposes. Depending on where
you live, your income from the Fund may be subject to state and local taxation.
You should consult your tax adviser in this regard.

SUPPLEMENTAL INFORMATION

You can receive at no cost supplemental information about the Fund by calling
the Trustee. The supplemental information includes more detailed risk disclosure
about the types of bonds that may be in the Fund's portfolio, general risk
disclosure concerning any insurance securing certain bonds, and general
information about the structure and operation of the Fund. The supplemental
information is also available from the SEC.

15
<PAGE>
REPORT OF INDEPENDENT ACCOUNTANTS

The Sponsors, Trustee and Holders of Municipal Investment Trust Fund, Insured
Series 400, Defined Asset Funds (the 'Fund'):

We have audited the accompanying statement of condition and the related defined
portfolio included in the prospectus of the Fund as of October 8, 1998. This

financial statement is the responsibility of the Trustee. Our responsibility is
to express an opinion on this financial statement based on our audit.

We conducted our audit in accordance with generally accepted auditing standards.
Those standards require that we plan and perform the audit to obtain reasonable
assurance about whether the financial statement is free of material
misstatement. An audit includes examining, on a test basis, evidence supporting
the amounts and disclosures in the financial statement. Our procedures included
confirmation of cash, securities and an irrevocable letter of credit deposited
for the purchase of securities, as described in the statement of condition, with
the Trustee. An audit also includes assessing the accounting principles used and
significant estimates made by the Trustee, as well as evaluating the overall
financial statement presentation. We believe that our audit provides a
reasonable basis for our opinion.

In our opinion, the financial statement referred to above presents fairly, in
all material respects, the financial position of the Fund as of October 8, 1998

in conformity with generally accepted accounting principles.

DELOITTE & TOUCHE LLP
NEW YORK, N.Y.

OCTOBER 8, 1998
STATEMENT OF CONDITION AS OF OCTOBER 8, 1998

TRUST PROPERTY

Investments--Bonds and Contracts to purchase Bonds(1) $ 10,122,686.00
Cash 20,000.00
Accrued interest to Initial Date of Deposit on underlying
Bonds 102,437.39
--------------------
Total $ 10,245,123.39
--------------------
--------------------
LIABILITIES AND INTEREST OF HOLDERS
Liabilities: Advance by Trustee for accrued interest (2) $ 102,437.39
Reimbursement of Sponsors for organization expenses (3) 20,000.00
--------------------
Subtotal 122,437.39
--------------------
Interest of Holders of 10,000,000 Units of fractional
undivided interest outstanding:
Cost to investors (3)(4)(5) 10,243,086.00
Organization expenses (3) and gross underwriting
commissions(4) (120,400.00)
--------------------
Subtotal 10,122,686.00
--------------------
Total $ 10,245,123.39
--------------------
--------------------

- ---------------

(1) Aggregate cost to the Fund of the bonds listed under Defined
Portfolio is based upon the offer side evaluation determined by the Evaluator at
the evaluation time on the business day prior to the Initial Date of Deposit.
The contracts to purchase the bonds are collateralized by an irrevocable letter
of credit which has been issued by The San Paolo Bank, New York Branch, in the
amount of $8,062,001.12 and deposited with the Trustee. The amount of the letter
of credit includes $7,980,288.20 for the purchase of $8,105,000 face amount of
the bonds, plus $81,712.92 for accrued interest.

(2) Representing a special distribution to the Sponsors by the Trustee
of an amount equal to the accrued interest on the bonds.
(3) A portion of the Unit Price consists of cash in an amount
sufficient to pay for costs incurred in establishing the Fund. These costs have
been estimated at $2.00 per 1,000 Units. A distribution will be made at the
close of the initial offering period to an account maintained by the Trustee
from which the organization expense obligation of the investors to the Sponsors
will be satisfied.
(4) Assumes the maximum up-front sales fee per 1,000 units of 1.00% of
the Unit Price. A deferred sales fee of $19.00 per 1,000 Units is payable over a
two-year period ($2.38 per 1,000 Units quarterly in the first year and $2.37 per
1,000 units quarterly in the second year). Distributions will be made to an
account maintained by the Trustee from which the deferred sales fee obligation
of the investors will be satisfied. If units are redeemed prior to the final
deferred sales charge deduction, the remaining portion of the deferred sales fee
applicable to such units will be transferred to the account on the redemption
date.
(5) Aggregate Unit Price (exclusive of interest) computed on the basis
of the offer side evaluation of the underlying bonds as of the evaluation time
on the business day prior to the Initial Date of Deposit.

16
<PAGE>
Defined
Asset FundsSM

HAVE QUESTIONS ? MUNICIPAL INVESTMENT TRUST FUND
Request the most recent free INSURED SERIES 400
Information Supplement (A Unit Investment Trust)

that gives more details about ---------------------------------------
the Fund, by calling: This Prospectus does not contain
The Bank of New York complete information about the
1-800-221-7771 investment company filed with the
Securities and Exchange Commission in
Washington, D.C. under the:

o Securities Act of 1933 (file no.
333-55781) and
o Investment Company Act of 1940 (file
no. 811-1777).

TO OBTAIN COPIES AT PRESCRIBED RATES--
WRITE: Public Reference Section of the
Commission
450 Fifth Street, N.W., Washington,
D.C. 20549-6009
CALL: 1-800-SEC-0330.
VISIT: http://www.sec.gov.
---------------------------------------
No person is authorized to give any
information or representations about
this Fund not contained in this
Prospectus or the Information
Supplement, and you should not rely on
any other information.
---------------------------------------
When units of this Fund are no longer
available, this Prospectus may be used
as a preliminary prospectus for a
future series, but some of the
information in this Prospectus will be
changed for that series.
Units of any future series may not be
sold nor may offers to buy be accepted
until that series has become effective
with the Securities and Exchange
Commission. No units can be sold in any
State where a sale would be illegal.

70138--10/98

<PAGE>
PART II
ADDITIONAL INFORMATION NOT INCLUDED IN THE PROSPECTUS

A. The following information relating to the Depositors is incorporated by
reference to the SEC filings indicated and made a part of this Registration
Statement.

I. Bonding arrangements of each of the Depositors are incorporated by reference
to Item A of Part II to the Registration Statement on Form S-6 under the
Securities Act of 1933 for Municipal Investment Trust Fund, Monthly Payment
Series--573 Defined Asset Funds (Reg. No. 333-08241).

II. The date of organization of each of the Depositors is set forth in Item B
of Part II to the Registration Statement on Form S-6 under the Securities Act of
1933 for Municipal Investment Trust Fund, Monthly Payment Series--573 Defined
Asset Funds (Reg. No. 333-08241) and is herein incorporated by reference
thereto.

III. The Charter and By-Laws of each of the Depositors are incorporated herein
by reference to Exhibits 1.3 through 1.12 to the Registration Statement on Form
S-6 under the Securities Act of 1933 for Municipal Investment Trust Fund,
Monthly Payment Series--573 Defined Asset Funds (Reg. No. 333-08241).

IV. Information as to Officers and Directors of the Depositors has been filed
pursuant to Schedules A and D of Form BD under Rules 15b1-1 and 15b3-1 of the
Securities Exchange Act of 1934 and is incorporated by reference to the SEC
filings indicated and made a part of this Registration Statement:

Merrill Lynch, Pierce, Fenner & Smith Incorporated 8-7221

Salomon Smith Barney Inc. ................................ 8-8177
PaineWebber Incorporated.................................. 8-16267
Dean Witter Reynolds Inc. ................................ 8-14172

------------------------------------

B. The Internal Revenue Service Employer Identification Numbers of the
Sponsors and Trustee are as follows:

Merrill Lynch, Pierce, Fenner & Smith Incorporated 13-5674085
Salomon Smith Barney Inc. ................................ 13-1912900

PaineWebber Incorporated.................................. 13-2638166
Dean Witter Reynolds Inc. ................................ 94-0899825
The Bank of New York, Trustee............................. 13-4941102

UNDERTAKING

The Sponsors undertake that they will not instruct the Trustee to accept from
(i) AMBAC Indemnity Corporation; Financial Guaranty Insurance Company, MBIA
Insurance Corporation or any other insurance company affiliated with any of the

Sponsors, in settlement of any claim, less than an amount sufficient to pay any
principal or interest (and, in the case of a taxability redemption, premium)
then due on any Security in accordance with the municipal bond guaranty
insurance policy attached to such Security or (ii) any affiliate of the Sponsors
who has any obligation with respect to any Security, less than the full amount
due pursuant to the obligation, unless such instructions have been approved by
the Securities and Exchange Commission pursuant to Rule 17d-1 under the
Investment Company Act of 1940.

II-1
<PAGE>
SERIES OF DEFINED ASSET FUNDS
DESIGNATED PURSUANT TO RULE 487 UNDER THE SECURITIES ACT OF 1933

SEC
SERIES NUMBER FILE NUMBER
- --------------------------------------------------------------------------------
Defined Asset Funds Municipal Defined Fund.................. 333-58397

CONTENTS OF REGISTRATION STATEMENT
The Registration Statement on Form S-6 comprises the following papers and
documents:

The facing sheet of Form S-6.

The Cross-Reference Sheet (incorporated by reference to the Cross-Reference
Sheet to the Registration Statement of Defined Asset Funds Municipal Series,
1933 Act File No. 33-54565).

The Prospectus.

Additional Information not included in the Prospectus (Part II).

The following exhibits:

1.1 --Form of Trust Indenture (incorporated by reference to Exhibit 1.1 to
the Registration Statement of Defined Asset Funds Municipal Defined
Fund Series 2, 1933 Act File No. 333-62185).
1.1.1 --Form of Standard Terms and Conditions of Trust Effective October 21,
1993 (incorporated by reference to Exhibit 1.1.1 to the Registration
Statement of Municipal Investment Trust Fund, Multistate Series-48,
1933 Act File No. 33-50247).
1.2 --Form of Master Agreement Among Underwriters (incorporated by reference
to Exhibit 1.2 to the Registration Statement of The Corporate Income
Fund, One Hundred Ninety-Fourth Monthly Payment Series, 1933 Act File
No. 2-90925).
2.1 --Form of Certificate of Beneficial Interest (included in Exhibit
1.1.1).
3.1 --Opinion of counsel as to the legality of the securities being issued
including their consent to the use of their name under the headings
'How The Fund Works--'Legal Opinion' in the Prospectus.
4.1 --Consent of the Evaluator.
5.1 --Consent of independent accountants.

9.1 --Information Supplement (incorporated by reference to Exhibit 9.1 to
Amendment No. 4 to the Registration Statement of Municipal Investment
Trust Fund, Insured Series--207, 1933 Act File No. 33-54037).

R-1
<PAGE>
DEFINED ASSET FUNDS

MUNICIPAL INVESTMENT TRUST FUND
SIGNATURES

The registrant hereby identifies the series number of Defined Asset Funds
listed on page R-1 for the purposes of the representations required by Rule 487
and represents the following:

1) That the portfolio securities deposited in the series as to which this
registration statement is being filed do not differ materially in type
or quality from those deposited in such previous series;

2) That, except to the extent necessary to identify the specific portfolio
securities deposited in, and to provide essential information for, the
series with respect to which this registration statement is being filed,
this registration statement does not contain disclosures that differ in
any material respect from those contained in the registration statements
for such previous series as to which the effective date was determined
by the Commission or the staff; and

3) That it has complied with Rule 460 under the Securities Act of 1933.

PURSUANT TO THE REQUIREMENTS OF THE SECURITIES ACT OF 1933, THE REGISTRANT
HAS DULY CAUSED THIS REGISTRATION STATEMENT OR AMENDMENT TO THE REGISTRATION
STATEMENT TO BE SIGNED ON ITS BEHALF BY THE UNDERSIGNED THEREUNTO DULY

AUTHORIZED IN THE CITY OF NEW YORK AND STATE OF NEW YORK ON THE 8TH DAY OF
OCTOBER, 1998.

SIGNATURES APPEAR ON PAGES R-3, R-4, R-5 AND R-6.

A majority of the members of the Board of Directors of Merrill Lynch,
Pierce, Fenner & Smith Incorporated has signed this Registration Statement or
Amendment to the Registration Statement pursuant to Powers of Attorney
authorizing the person signing this Registration Statement or Amendment to the
Registration Statement to do so on behalf of such members.

A majority of the members of the Board of Directors of Salomon Smith Barney

Inc. has signed this Registration Statement or Amendment to the Registration
Statement pursuant to Powers of Attorney authorizing the person signing this
Registration Statement or Amendment to the Registration Statement to do so on
behalf of such members.

A majority of the members of the Executive Committee of the Board of
Directors of PaineWebber Incorporated has signed this Registration Statement or
Amendment to the Registration Statement pursuant to Powers of Attorney
authorizing the person signing this Registration Statement or Amendment to the
Registration Statement to do so on behalf of such members.

A majority of the members of the Board of Directors of Dean Witter Reynolds
Inc. has signed this Registration Statement or Amendment to the Registration
Statement pursuant to Powers of Attorney authorizing the person signing this
Registration Statement or Amendment to the Registration Statement to do so on
behalf of such members.

R-2
<PAGE>
MERRILL LYNCH, PIERCE, FENNER & SMITH INCORPORATED
DEPOSITOR

By the following persons, who constitute Powers of Attorney have been filed
a majority of under
the Board of Directors of Merrill Form SE and the following 1933 Act
Lynch, Pierce, File
Fenner & Smith Incorporated: Number: 33-43466 and 33-51607

HERBERT M. ALLISON, JR.
BARRY S. FREIDBERG
EDWARD L. GOLDBERG
STEPHEN L. HAMMERMAN
JEROME P. KENNEY
DAVID H. KOMANSKY
DANIEL T. NAPOLI
THOMAS H. PATRICK
JOHN L. STEFFENS
ROGER M. VASEY
ARTHUR H. ZEIKEL

ERNEST V. FABIO

(As authorized signatory for Merrill Lynch, Pierce,
Fenner & Smith Incorporated and
Attorney-in-fact for the persons listed above)

R-3
<PAGE>

SALOMON SMITH BARNEY INC.
DEPOSITOR

By the following persons, who constitute a majority of Powers of Attorney
the Board of Directors of Salomon Smith Barney Inc.: have been filed

under the 1933 Act
File Numbers:
33-49753,
33-55073,
333-41765 and
333-10441

JAMES DIMON
DERYCK C. MAUGHAN

By GINA LEMON
(As authorized signatory for

Salomon Smith Barney Inc. and

Attorney-in-fact for the persons listed above)

R-4
<PAGE>
PAINEWEBBER INCORPORATED
DEPOSITOR

By the following persons, who constitute Powers of Attorney have been filed
the Board of Directors of PaineWebber under
Incorporated: the following 1933 Act File
Number: 2-61279

MARGO N. ALEXANDER
TERRY L. ATKINSON
BRIAN M. BAREFOOT
STEVEN P. BAUM
MICHAEL CULP
REGINA A. DOLAN
JOSEPH J. GRANO, JR.
EDWARD M. KERSCHNER
JAMES P. MacGILVRAY
DONALD B. MARRON
ROBERT H. SILVER
MARK B. SUTTON
By
ROBERT E. HOLLEY
(As authorized signatory for
PaineWebber Incorporated
and Attorney-in-fact for the persons listed above)

R-5
<PAGE>
DEAN WITTER REYNOLDS INC.
DEPOSITOR

By the following persons, who constitute Powers of Attorney have been filed
a majority of under Form SE and the following 1933
the Board of Directors of Dean Witter Act File Numbers: 33-17085 and
Reynolds Inc.: 333-13039

RICHARD M. DeMARTINI
ROBERT J. DWYER
CHRISTINE A. EDWARDS
CHARLES A. FIUMEFREDDO
JAMES F. HIGGINS
MITCHELL M. MERIN
STEPHEN R. MILLER
RICHARD F. POWERS III
PHILIP J. PURCELL
THOMAS C. SCHNEIDER
WILLIAM B. SMITH
By
MICHAEL D. BROWNE
(As authorized signatory for
Dean Witter Reynolds Inc.
and Attorney-in-fact for the persons listed above)

R-6

<PAGE>
EXHIBIT 3.1
DAVIS POLK & WARDWELL
450 LEXINGTON AVENUE
NEW YORK, NEW YORK 10017
(212) 450-4000

OCTOBER 8, 1998

Municipal Investment Trust Fund,
Insured Series 400

Defined Asset Funds

Merrill Lynch, Pierce, Fenner & Smith Incorporated

Salomon Smith Barney Inc.

PaineWebber Incorporated
Dean Witter Reynolds Inc.
c/o Merrill Lynch, Pierce, Fenner & Smith Incorporated
Defined Asset Funds
P.O. Box 9051
Princeton, NJ 08543-9051

Dear Sirs:

We have acted as special counsel for you, as sponsors (the Sponsors) of
Municipal Investment Trust Fund, Insured Series 400, Defined Asset Funds (the

'Fund'), in connection with the issuance of units of fractional undivided
interest in the Fund (the 'Units') in accordance with the Trust Indenture
relating to the Fund (the 'Indenture').

We have examined and are familiar with originals or copies, certified or
otherwise identified to our satisfaction, of such documents and instruments as
we have deemed necessary or advisable for the purpose of this opinion.

Based upon the foregoing, we are of the opinion that (i) the execution and
delivery of the Indenture and the issuance of the Units have been duly
authorized by the Sponsors and (ii) the Units, when duly issued and delivered by
the Sponsors and the Trustee in accordance with the Indenture, will be legally
issued, fully paid and non-assessable.

We hereby consent to the use of this opinion as Exhibit 3.1 to the
Registration Statement relating to the Units filed under the Securities Act of
1933 and to the use of our name in such Registration Statement and in the
related prospectus under the heading 'How the Fund Works--Legal Opinion'.

Very truly yours,

DAVIS POLK & WARDWELL

<PAGE>
EXHIBIT 4.1

KENNY INFORMATION SYSTEMS,
A Division of J. J. Kenny Co., Inc.
65 Broadway
New York, New York 10006
Telephone: 212/770-4422
Fax: 212/797-8681
Frank A. Ciccotto, Jr.
Vice President

October 8, 1998

Merrill Lynch Pierce Fenner & Smith
Incorporated
Defined Asset Funds
P.O. Box 9051
Princeton, NJ 08543-9051
The Bank of New York
101 Barclay Street--17W
New York, N.Y. 10268

Re: Municipal Investment Trust Fund,
Insured Series 400
Defined Asset Funds

Gentlemen:

We have examined the Registration Statement File No. 333-55781 for the

above-captioned fund. We hereby acknowledge that Kenny Information Systems, a
Division of J. J. Kenny Co., Inc. is currently acting as the evaluator for the
fund. We hereby consent to the use in the Registration Statement of the
reference to Kenny Information Systems, a Division of J. J. Kenny Co., Inc. as
evaluator.

In addition, we hereby confirm that the ratings indicated in the
Registration Statement for the respective bonds comprising the trust portfolio
are the ratings indicated in our KENNYBASE database as of the date of the
Evaluation Report.

You are hereby authorized to file a copy of this letter with the Securities
and Exchange Commission.

Sincerely,

FRANK A. CICCOTTO, JR.
VICE PRESIDENT

<PAGE>
EXHIBIT 5.1
CONSENT OF INDEPENDENT ACCOUNTANTS

The Sponsors and Trustee of Municipal Investment Trust Fund, Insured Series 400,
Defined Asset Funds:

We consent to the use in this Registration Statement No. 333-55781 of our report
dated October 8, 1998 relating to the Statement of Condition of Municipal
Investment Trust Fund, Insured Series 400, Defined Asset Funds, and to the
reference to us under the heading 'How the Fund Works--Auditors' in the
Prospectus which is a part of this Registration Statement.

DELOITTE & TOUCHE LLP
New York, N.Y.
October 8, 1998

<ARTICLE> 6
<MULTIPLIER> 1

<S> <C>
<PERIOD-TYPE> OTHER
<FISCAL-YEAR-END> SEP-30-1998
<PERIOD-END> OCT-08-1998
<INVESTMENTS-AT-COST> 10,122,686
<INVESTMENTS-AT-VALUE> 10,122,686
<RECEIVABLES> 102,437
<ASSETS-OTHER> 20,000
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 10,245,123
<PAYABLE-FOR-SECURITIES> 0
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 122,437
<TOTAL-LIABILITIES> 122,437
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 10,122,686
<SHARES-COMMON-STOCK> 10,000,000
<SHARES-COMMON-PRIOR> 0
<ACCUMULATED-NII-CURRENT> 0
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> 0
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> 0
<NET-ASSETS> 10,122,686
<DIVIDEND-INCOME> 0
<INTEREST-INCOME> 0
<OTHER-INCOME> 0
<EXPENSES-NET> 0
<NET-INVESTMENT-INCOME> 0
<REALIZED-GAINS-CURRENT> 0
<APPREC-INCREASE-CURRENT> 0
<NET-CHANGE-FROM-OPS> 0
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> 0
<DISTRIBUTIONS-OF-GAINS> 0
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 10,000,000
<NUMBER-OF-SHARES-REDEEMED> 0
<SHARES-REINVESTED> 0
<NET-CHANGE-IN-ASSETS> 0
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> 0
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 0
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 0
<AVERAGE-NET-ASSETS> 0
<PER-SHARE-NAV-BEGIN> 0
<PER-SHARE-NII> 0
<PER-SHARE-GAIN-APPREC> 0
<PER-SHARE-DIVIDEND> 0
<PER-SHARE-DISTRIBUTIONS> 0
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 0
<EXPENSE-RATIO> 0
<AVG-DEBT-OUTSTANDING> 0
<AVG-DEBT-PER-SHARE> 0

</TABLE>