The Postal Service has added a little frosting to the normally limited philatelic observance of a presidential inauguration by making its usual "Inauguration Day" machine cancel available at three locations Jan. 20.

The special postmark will be applied at the Washington D.C., Main Post Office, as usual, and also at Plains, Ga., and Ceylon, Minn. Plains is the hometown of President-elect Jimmy Carter, and Ceylon is the birthplace of Vice President-elect Walter F. Mondale.

Mail orders must be received by one of the three post offices prior to Jan. 20. Individuals may address pain or especially cacheted envelopes, affix a 13-cent stamp and send this material to the postmaster at Washington, D.C., 20013; Plains, Ga. 31780, or Ceylon, Minn. 56121. The outer envelope or wrapper should be marked "Inauguration Day Cancels."

Covers bearing previously canceled stamps will postmarked Jan. 20 only when presented in person for what is referred to as handback service, and only when additional stamps at the first-class rate have been affixed. Oversized cards, posters and other memorabilla will be canceled only when presented for handback service.

There is no limit to the number of machine cancellations which may be ordered by mail, but handstamp cancels are limited to 100 per person unless prior approval is obtained from the Stamps Division, U.S. Postal Service, Washington, D.C. 20260.

President-elect Carter's interest in and plans for the Postal Service's philatelic program are not known. He has gone on record as proposing that the Postmaster General be made a presidential appointee, subject to confirmation by the Senate.

The President-elect has also indicated that he will require the Board of Governors to give more time and attention to the management of the Postal Service, and take over the setting of rates after the Postal Rate Commission is abolished.

He has stated that he will support the moratorium on rate increases and service reductions until the Study Commission created by Congress makes its findings known.

One thing is certain - there has been no series of "interviews" by a transition team of postal officials-designate, geared to the purge of officials of the "wrong party."

According to the German Postal Specialist, official organ of the Germany Philatelic Society, the United States Postal Service is expected to set up a special agency in the Federal Republic of Germany for the sale of U.S. stamps. It is hinted that such an agency would be along the lines of those Jacques Minkus operates in this country for Israel and Nationalist China.

A supplement to the Post Service's 1977 Treasury of Stamps album, distributed gratis at about 10,000 post offices across the country before Christmas, is in production, and will provide spaces for the four commemoratives Postmaster General Benjamin Bailar added to this year's schedule Dec. 7.

Those who picked up the 1977 Treasury of Stamps album should contact their local postmaster to ascertain when the supplement page (also free) will be available.

The Vatican City plans to issue five special series of stamps this year, a pack of six postcards reproducing the Architectural Heritage stamps of 1975 and a new type of aerogram.

The special issues will commemorate the 750th anniversary of the death of St. Francis of Assisi, the sixth centenary of the return of Pope Gregory XI from Avignon to Rome and the Feast of the Assumption Two units will feature masterpieces of classical and Christian art contained in the Postifical Museums and Galleries.

North Korea will bring out 19 special issues this year, involving 27 stamps. Included are five "ceramics" sets, and single stamps for Philatelic Week and the 2,600th anniversary of Buddha's birth.

Guyana, The Gambia, Nigeria and Mauritius issued stamps earlier this month publicating the Second World Black and Africa Festival of Arts and Culture, and the British Antarctic Territory released four appropriately long stamps Jan. 4 in support of the Conservation of Whales program.

France has issued, or scheduled for issue, single adhesives relating to its National Police, the Musee de I' Atlantique at Port Louis, Guyane and an oversize art stamp reproducing a Vlaminck still-life, plus pair of semi-postals showing statues in the Brou Church. Andocra produced two butterfly stamps for nature conservation.

Brazil closed off 1976 with a single stamp noting the 25th anniversary of its Thankgiving Day, two adhesives showing navy uniforms of 1808 and 1940, and another single recognizing its Bureau of Standards.

Norway will also participate in the five-nation Nordic omnibus conservation stamp program Feb. 2. Its pair of adhesives (125 and 140 ore) will also show five water lilies floating on pure water under a clear sky.

The America First Day Cover Society has elected new officers for 1977. Unopposed candidates were Mrs. Edward Siakin of Gales Ferry, Conn., president; Allison W. Cusick, Stow, Ohio, executive vice president; Mrs. Marge Finger, Elberon, N.J., executive secretary, Joe Moberty, Kansas City, Missouri, corresponding secretary and George Connes, Boonton, N.J., treasurer.

Milestone of Flight cover No. 47, marking the 40th anniversary of Howard Hughes' record-setting transcontinental flight of Jan. 19, 1937, has been announced by the National Air and Space Museum. Orders ($1.25 per cover, limit of five) may be sent to "Milestones of Flight, National Air and Space Museum Smithsonian Institution, Washington, D.C. 20560. Checks should be payable to the Smithsonian Institution.

There will be changes in the Department of the Treasury and the Bureau of the Mint starting Thursday. Werner Michael Blumenthal will become Secretary of the Treasury, succeeding William E. Simon, and his signature will appear on all United States paper money.

Mrs. Mary Brooks, director of the Bureau of the Mint, plans to retire shortly, even though she could remain for several years as a result of her most recent appointment. Brooks started her term as the 28th Mint director Sept. 18, 1969, and was reappointed in 1974.

The transition is not expected to affect James A. Conlon, who was appointed Director of the Bureau of Engraving and Printing Oct. 5, 1967.

There will be a plethora of inaugural medals, though only those struck by the Franklin Mint will rate as official. Mediallic Art Co. has already announced twin Carter-Mondale inaugural medals in four editions, and the Lincoln Mint is producing a one-inch gold inaugural medal showing President-elect Carter being sworn in by the Chief Justice of the Supreme Court while Vice President-elect Mondale looks on.

Forerunners of inaugural medals were the bronze medals produced in 1893 for Grover Cleveland and in 1897 for William McKinley.

McKinley's second inaurguration, in 1901, was the occasion for the striking of the initial official inaugural medal, and Theodore Roosevelt had two produced in 1905. One - for committee members - was designed by Charles Barber and George Morgan, and the other - for prominent officials - was done by Augustus Saint-Gaudens and Adolph Weinman.

Hank Spangenberger, in the Jan. 5 issue of Coin World, notes that no official inaugural medals were struck for Warren G. Harding and Calvin Coolidge. There were unofficial pieces.

Franklin D. Roosevelt had four official inaugural medals; Dwight D. Eisenhower shared his second inaugural medal with his Vice President, Richard M. Nixon. Nixon, in turn, was portrayed alone on his first official medal, then shared his second with Spiro Agnew.

The first official vice presidential medal was struck for Gerald R. Ford when replaced Agnew in 1973, and Ford was subsequently recognized when he became the 38th President following Nixon's resignation. Ford's Vice President, Nelson A. Rockefeller, was accorded an interim official inaugural medal.

An exhibit of inaugural medals from William McKinley to Jimmy Carter will open tomorrow in the Smithsonian's National Museum of History and Technology and will continue through February. It will be located in the third-floor lounge near the entrance to the Hall of Money and Medals.

The International Criminal Police Organization's General Secretariat, headquartered in Saint-Cloud, France, has released a 60-page listing of forged United States currency. As might be expected 23 of the reported forgeries involved the $20 bill and 22 carried the $100 denomination.

In most instances the red and blue filaments (fibres) were not imitated in the established counterfeits, but there were some examples which had printed red and blue lines simulating the fibres.

A $5 Federal Reserves Bank of Atlanta, Ga., forged banknote did not rate as a deceptive note, but it was passed literally around the world in 2 1/2 years, appearing in New York, London, Madrid, Frankfurt, Paris, Tokyo and Gibraltar.

Virtually every counterfeit U.S. banknote was described as not deceptive (to the informed). It is interesting to note that virtually all of the $5, $20 and $50 counterfeit bills first appeared in the United States or Canada, while the $100 bills made their debut in Switzerland.

Cities within the United States in which counterfeit banknotes first appeared were Los Angeles ($20); Indianapolis ($20); New York ($5); Syosset, N.Y. ($100); Miami ($50); New Orleans ($100); Dayton Beach ($100); Portsmouth, New Hampshire ($20); Bal Harbour, Fla. ($100); Brownsville, Texas ($50); and Honolulu ($20).

Ottawa as a city, and Ontario as a Province, were the locales for most of the discoveries in Canada, and all of the counterfeits "discovered" in Switzerland were printed in Tel Aviv, Israel.

Belgium is releasing a 250-franc silver commemorative coin marking the 25th anniversary of the coronation of King Baudouin. Sales will be in sets of two, with inscriptions in Dutch and French.

Panama has authorized the Franklin Mint to strike 500-balboa gold coins portraying Vasco de Nunez de Balboa on the obverse. This is stated to be the largest and heaviest gold coin ever struck by Franklin Mint. Orders for proofs, priced at $575 apiece, closed Dec. 15.

A listing of numismatic publications presently available is being distributed by James A. Brown, 97 Wilson Ave., Newark, N.Y. 07105.