EEPOET OF NATIONAL MUSEUM., 1922. 107 



driven, as over against the chain drive. In the early days of the auto- 

 laobile industry in this country both the steam engine and the 

 internal-combustion engine were experimented with as a source of 

 motive power. One of the most successful of these steam-driven 

 automobiles was that knoAvn as the •' Locomol)ile," operated by a 

 two-cylinder steam engine developed by Stanley. The division was 

 very fortunate in receiving as a gift from Louis S. Clarke, Ard- 

 more, Pa., one of these two-cylinder steam engines used in a Loco- 

 mobile, about 1901. Inasmuch as the automobile truck is the latest 

 development in the transportation of commodities overland, the 

 division was pleased to be able to add to its series of models show- 

 ing the improvements in this type of transportation two one-quarter 

 size models of automobile trucks. These were presented by The 

 x\utocar Co., Ardmore, Pa. 



Metroloijy. — The branch of metrology devoted to mechanical cal- 

 culators Avas enhancetl by the accession of a series of three ma- 

 chines to illustrate the successive steps in the development of the 

 reversible crank type originally patented by F. S. Baldwin in 

 IbTo. This accession is the gift of the Monroe Calculating Machine 

 Co., Orange, N. J. 



During the course of the year the time-keeping collections were 

 further increased by the gift of 27 gold and silver watches and watch 

 movements, heretofore unrepresented in the Museum's collections, 

 i'hese were presented by (ieorge W. Spier, Chevy Chase, Md. 



Electrical engineering. — From time to time in the past the divi- 

 sion has succeeded in procuring objects visualizing improvements 

 in the incandescent electric lamp. Through the gift of 94 incan- 

 descent lamps from the Edison Lamp Works of the General Electric 

 Co., Harrison, N. J., it is gratifying to note that the division now 

 has a complete series of incandescent lamps showing all the steps in 

 the development of the Edison type, beginning with the original 

 patent granted in 1879 and ending with the many varieties in use 

 in 1922. Of this series, all are original lamp.s with the exception 

 of the lamp first developed by Edison in his laboratory in Menlo 

 Park, X. J., in October, 1879, and the model lamp submitted 

 to the Patent Office when application for patent rights was made. 

 These two lamps, however, have been accurately reproduced and 

 form part of the collection. 



PEESERVIXG AND IXSTALLIN'G COLfiBCTIONS. 



One of the important features of the exhibits in the division of 

 mineral technology is working models. The time spent by the pre- 

 parator in maintaining these exhibits has been so great that it was 

 considered advisable to make a study of the conditions in the hope 

 of reducing the time element. As a result a number of mechanical 



