106 KKPOllT OF NATIONAL MUSEUM, 1!>22. 



ACOKSSIONS DESKRVIXG SPECIAL VDTU.'E. 



In the division of mineral technology four of the fiA^e accessions 

 consist of 28 transparencies, colored and imcolored, which are used 

 verj' appropriately in further amplifying several of the division's 

 industrial exhibits. Twenty of these transparencies were made in 

 the Museum's photographic laboratory — 12 for the natural gas 

 exhibit and 8 for the exhibit showing the manufacture of sodium 

 compounds b}' the Solvay process; four transparencies were received 

 as a gift from the Union Sulphur Co., Xew York City, showing 

 interesting phases of the sulphur-mining industry as practiced in 

 Louisiana ; and four colored transparencies illustrating a like num- 

 ber of the more important uses of Portland cement, received as a gift 

 of the Atlas Portland Cement Co., New York City. The fifth 

 exhibit consists of a case containing a technological chart or flow 

 sheet showing the steps, with products, in the manufacture of the 

 thermal insulator, *■' 85 per cent magnesia."' This exhibit is used 

 in conjunction with the division's asbestos products exhibit and was 

 received as a gift from the Magnesia Association of America, Phila- 

 delphia, Pa. 



Oi the 32 accessions received b}^ the division of mechanical tech- 

 nology and distributed to its several branches of activities, all are 

 worthy of note. Special reference, however, must be given to the 

 following : 



Land transportation.— 'Y\\e exhibit visualizing the development of 

 the locomotive was enhanced by a complete working model, one 

 twent^^-fourth actual size, made of brass and steel, of the " Ameri- 

 can " type locomotive. It illustrates the early twentieth century 

 development of the type used jjrincipally for high-speed passenger 

 service, a type previously unrepresented in the division's collections. 

 The model is loaned by John S. Clarke, Ardmore, Pa. The divi- 

 sion's exhibit relating to the development of the locomotive con- 

 tains many gaps which it was hoped could be gradually closed by 

 the construction of well-made models. The facilities at hand for 

 such work are very limited, however, and the time required would 

 be very extensive. As an alternative, therefore, the division was 

 pleased to I'eceive as a gift from the Baldwin Locomotive Works, 

 Philadelphia, Pa., a series of 71 photographic copies from original 

 negatives and drawings illustrating types of locomotives made by 

 this company between 1832 and 1922. When these photographs are 

 installed in the locomotive series, it is believed that the visitor will 

 obtain a fairly comprehensive idea of this important subject. 



The exhibit illustrating the development of the gasoline automo- 

 bile was enriched through the gift of The Autocar Co., Ardmore, 

 Pa., of an original full-size machine, designed by Louis S. Clarke 

 and constructed in 1901. Its particular feature is that it is shaft 



