REPORT OF THE SECRETARY. 155 



prompt reports of progress along all lines. This information will 

 be disseminated in such a way that the work in the various States 

 can be so correlated and coordinated as to minimize the duplication 

 which is now so much in evidence. 



TESTING OF ROAD MATERIALS. 



In the routine testing and examination of road materials great 

 progress has been made along established lines. The total number 

 of samples tested during the year was 1,168, an increase of 59 per 

 cent over the number received and tested during the preceding year. 

 In addition to these routine tests, investigations were made with a 

 view to the utilization of slag and other by-products in road building, 

 and these were extended to comprise field experiments through the 

 construction of short sections of road at Youngstown, Ohio, and 

 Ithaca, N. Y. These investigations have developed the fact that 

 practically all the basic open-hearth slags are well adapted to road 

 construction, especially when used as binding materials. It has been 

 found that by adding quicklime to blast-furnace slag screenings the 

 cementing properties are greatly increased. These investigations 

 will be continued during the next fiscal year. 



CULVERTS AND BRIDGES FOR HIGHWAYS. 



The need for better culverts and bridges for our public highways 

 is becoming evident, both from the point of view of economy and 

 safety for the public. Information on this subject in suitable form 

 has been in the past, and still remains, fragmentary and scattered. 



By far the larger number of such structures that are needed are of 

 the shorter spans — 50 feet or less — ^and in the past they have been 

 built of timber, which is, however, constantly increasing in price, and 

 requires a relatively much larger expenditure for maintenance. Much 

 economy can be effected, and more durable and safer structures can 

 be built out of concrete or masonry, provided that the required infor- 

 mation and skilled supervision may be had. 



Owing to the fact that the individual pieces of work are small, 

 those in responsible charge have not felt warranted in incurring the 

 expense incident to the employment of skilled engineering assistants. 



Such information as is referred to above is now being collected, 

 and it is hoped that much of value will be in shape for publication 

 and distribution during the coming fiscal year. 



The published information will be supplemented by personal inspec- 

 tion and advice by engineers of the Office when request is made 

 through the local authorities. 



