BUREAU OF PUBLIC ROADS. 383 



ADDRESSES, LECTURES, AND PAPERS. 



Technical advice has been rendered during the year on legishition, 

 organization, management, construction, and maintenance. This 

 work has been carried on through conferences, lectures, and the pres- 

 entation of papers. Efforts were made during the year to limit this 

 work to meetings and conferences of official bodies of sufficient State 

 or nation-wide importance to justify tlie attendance of department 

 representatives. Practically all propaganda work has been discop- 

 tinued during the period of the war. 



A total of. 149 lectures was delivered, as compared with 263 during 

 1917 and 655 in 1916. The total attendance at such meetings was 

 19,561, as compared With 43,184 in 1917 and 92,610 in 1916. 



MODELS AND EXHIBITS. 



Practical demonstrations by means of models and other exhibit 

 materials were made during the year to illustrate the various activi- 

 ties of the office. This exhibit material was built and maintained by 

 the office, but all expenses of transportation and installation were 

 paid by the organizations benefited. All exhibit work was carried 

 on in cooperation with the Office of Exhibits of the Department. 

 Exhibits were made at nine places during the year as follows : State 

 Fair, Hutchinson, Kans., September, 1917; International Wheat 

 Show, Wichita, Kans., October 1 to 13; National Farm and Live 

 Stock Show, New Orleans, La., November 10 to 19; Massachusetts 

 Institute of Technology, February to October ; New York Electrical 

 Exposition, October 10 to 20; Eochester (New York) Industrial 

 Exposition, September; International Exposition, Cleveland, Ohio, 

 September 1 to 9 ; State Fair, Dallas, Tex., October 13 to 28 ; Albe- 

 marle Highway Association and Chamber of Commerce, Charlottes- 

 ville, Va., November, 



PHOTOGRAPHIC WORK. 



The photographic laboratory developed 1,630 negatives, made 6,276 

 prints, 649 lantern slides, 177 bromide enlargements, and 555 photo- 

 stat prints. In addition to this work 1,332 lantern slides were col- 

 ored for lecture work and 5,235 maps were mounted on cloth. For 

 the benefit of various individuals and organizations, including em- 

 ployees of the office, 1,913 lantern slides, 5,203 prints, and 425 bromide 

 enlargements were loaned. At the close of the year the photographic 

 files contained 19,728 negatives, 51,332 prints, and 12,640 lantern 

 slides. 



ROAD MATERIAL TESTS AND RESEARCH. 



Research work, as compared with the preceding fiscal year, fell off 

 materially. This was due to loss of employees and inability to 

 replace them with experienced men ; also to the fact that cooperation 

 with other branches of the Government in war activities and super- 

 vision of material specifications and tests for Federal aid activities 

 consumed much time. Considerable assistance was given to the Fuel 

 Administration in connection with its activities on the United States 

 Highways Council. This work has to do with recommendations rela- 

 tive to granting permits for securing bituminous materials for road 



