REPORT OF THE CHEMIST. 



TJ. S. Department of Agriculture, 



Bureau of Chemistry, 

 Washington, D. C, July 24, 1901. 



Sir : I beg to submit herewith a statement of the work carried on 

 in tlie Division of Chemistry for the fiscal year ended June 30, 1901, 

 with plan of work in the Bureau of Chemistry for 1902 and proposed 

 work for 1903. 



Respectfully, H. W. Wiley, 



Chemist. 

 Hon. James Wilson, Secretary. 



WORK OF THE YEAR. 

 NEW WORK. 



The most important new work during the year was the establish- 

 ment of a laboratory for the investigation of the physical and chem- 

 ical properties of the materials used in building roads. This work 

 has both a high scientific and practical value in the construction of 

 good roads. 



It is a well-known fact that the agricultural value of farm products 

 depends largely upon the accessibility to markets. Accessibility to a 

 market is not judged alone by distance in miles from the place where 

 the crop is grown; it is judged rather by the facilities and cheapness 

 of transportation. New York City is a market which is reasonably 

 accessible to the West India Islands, on account of the cheapness of 

 transportation by water. It is, however, judged from a market point 

 of view, at a great distance from many places in New York State, in 

 the Adirondacks for instance. Farms which lie within a few miles of 

 a market are often so difficult to reach as to render it almost impossible 

 to realize any profit on the products of their fields. The building of 

 good roads is, therefore, directly related to the progress of agriculture. 



It is perfectly evident that many millions of dollars have been 

 wasted in the building of roads because the nature of the material 

 used for surfacing has not been known. The surface of a road must 

 be hard enough to resist the ordinary wear and tear of traffic, and 

 should be composed of materials which, when reduced to powder, 

 have a certain cementing value which prevents the comminuted 

 particles from being removed by wind and water. The character of 

 the materials used in a road must also be adapted to the kind of 

 traffic to which the road is to be subjected. A roadway constructed 

 for the light carriage traffic of a city and its suburbs should be com- 

 posed of quite different materials, placed in a different manner, from 

 a road over which heavily loaded wagons are to be drawn. 



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