788 ANNUAL REPORTS OF DEPARTMENT OF AGRICULTURE. 



On November 1, 1900, an cn<jjinccr from tlic Office, accompanied 

 by tlie Oflice photogjrapher, loft Wasliington on an extended tour, 

 for the purpose of securing pliotograplis and other data concerning 

 road construction and maintenance throughout tlie territory covered. 

 Tlxe object of tliis tour was to collect information for use in reportin|^ 

 the results of certain object-lesson and experimental work which 

 had been conducted by the Oflice and for illustrating^ certain contem- 

 plated publications, and also to afford a source of mformation from 

 which the engineers of the Oflice could post themselves as to the con- 

 ditions existing in those sections of the States visited, before enter- 

 ing upon any liighway work therein. This tour covered the period 

 from November 1, 1909, to January 8, 1910, and much valuable 

 data was obtained. It was not intended that the results of this 

 investigation should be published separately, but that they should be 

 for use as above outlined. 



Anotlier very important investigation was begun to ascertain the 

 economic eifect of road improvement upon communities. In this 

 work counties which liad voted to issue bonds for road purposes 

 were selected in different sections of the country and, before the bonds 

 were issued or the work of improvement begun, a careful study of 

 the agricultural and road conditions was matle along the line of the 

 roads to be improved. The following facts, illustrated by photo- 

 graphs, were ascertainefl : The value of tlie land; the character of the 

 crops hauled to market; the size of the loads; the distance to the 

 market; the cost of marketing the crops; the area of productivity of 

 the different crops; the condition of the schools and farm life; the 

 efficiency of the rural mail delivery service; railroad statistics of 

 incoming and outgoing freights at the points of investigation. This 

 investigation was begun in January, 1910, and will cover a period of 

 several years, since it can not be completed until the proceeds of the 

 bonds have been expended and the effects of the improved roads 

 noted. After the roads are completed, it is proposed' to examine 

 them again and note the beneficial effects which the improvements 

 have had upon conditions, illustrating these facts by new photo- 

 graphs. The information obtained by tliis investigation is intended 

 for publication as a comprehensive bulletin, showing the economic 

 value of road improvement. 



INVESTIGATIONS OF SLAG AND CEMENT. 



The work carried on in the petrographic laboratory embraced, 

 besides the usual routine examination of rocks for road making, an 

 extensive study of blast-furnace and open-hearth slags and Portland 

 cement clinkers to determine their road-making qualities. The 

 work is essentially a continuation and extension, under more favor- 

 able circumstances, of that of last year and the results have been 

 proportionately greater. 



Samples of basic open-hearth slag have been obtained from the 

 larger steel mills of the country and the laboratory investigations 

 have demonstrated that practically all of them are well adapted to 

 road construction, especially when used as binding material. These 

 conclusions have been amply confirmed by actual service tests, as in 

 the case of the experimental slag roads constructed last 3^ear under 

 the auspices of the Office, at Youngstown, Ohio, and Ithaca, N. Y. 



