6 REPOET OF NATIONAL MUSEUM, 1923. 



industry and their use as substitutes for such natural raw materials 

 as ivorj", bone, horn, tortoise shell, amber, etc. Beautiful specimens 

 of silks, woolen fabrics and mohair upholstery textiles were con- 

 tributed by American manufacturers to show the progress of textile 

 industries in this country. Specimens illustrating the manufacture 

 and use of sulphite wood, and samples of cypress wood believed to 

 be over 30,000 years old were added to the collections in the section 

 of wood technology. The division of medicine received specimens 

 showing the use of chaulmoogra. oil derivatives in the treatment of 

 leprosy; ancient surgical instruments; Italian hospital supplies of 

 the type used in the World War; also medical manuscripts. 



In the division of mechanical technology the objects acquired 

 now make possible the visualization of the development of methods 

 of communication from those of smoke and fire to those of wireless 

 telegraphy with all of the essential intermediate steps. A model 

 illustrating the manufacture of coal gas and carburetted water gas 

 was made especially for the Museum, also series of models illustrat- 

 ing mechanical principles and the fundamental elements and devices 

 used in machines. 



Almost the beginning and the end of type composition were illus- 

 trated in the year's acquisitions by a leaf of the Gutenberg Bible, 

 one of the first books printed from movable type, and by examples 

 of the monotype system of casting and composing justified lines of 

 single type. There were also wood block prints and etchings by 

 Helen Hyde and by other American artists, pictorial photographic 

 prints by American and foreign photographers of note, and an early 

 motion picture projector. 



The large historical military collection of the Military Service In- 

 stitution for many years displayed on Governors Island, N. Y,, was 

 transferred to the National Museum, some of its most popular com- 

 ponents being the war horse of Gen. Philip H. Sheridan famous for 

 the ride to Winchester; a cannon captured from the British troops 

 commanded by General Burgoyne at Saratoga in 1777; a mortar 

 made by D. King of Philadelphia ; and a sword owned by Commo- 

 dore Stephen Decatur, U. S. Navy. This collection, forming a sepa- 

 rate exhibition unit, was installed in a small room on the second 

 floor of the southeast range of the Arts and Industries Building, 

 which was opened as an exhibition hall for the first time this year. 



Of unparalleled importance is the large collection of numismatic 

 material formerly exhibited in the U. S. Mint in Philadelphia, which 

 was transferred to the Museum by the U. S. Treasury Department in 

 June, 1923. This contains an exceptionally fine collection of United 

 States coins, medals, and paper currency besides a large number of 

 ancient coins, a fair representation of mediaeval European coins, and 



