22 BULLETIN 220, U. S. DEPARTMENT OF AGRICULTURE. 



example in the use of the small culvert where the walk leads over 

 the ditch before reaching the road. This same use of the culvert is 

 made at the driveway entrance to the house. Architectural features 

 of Monticello, the former home of Thomas Jefferson, were followed 

 in the construction of this dwelling. The rustic summer house and 

 the spring house in its cool white furnish pleasing sights across the 

 fields, which have been cleared of undergrowth and left with only a 

 few well-placed trees and shrubs. 



ROAD MACHINERY. 



Many good roads were built before the invention of road-building 

 machinery, but modern machinery has done much to simplify the 

 process and reduce the cost of road construction. The power-driven 

 road roller has made possible the construction of a macadam road in 

 a few days or weeks, where formerly traffic was required to make its 

 way laboriously over the loose stones for months before the surface 

 became even' reasonably consolidated. 



The steam road roller was invented by M. Louis Lemoine, of Bor- 

 deaux, France. The French Government granted him a patent in 

 1859. The first English patent was granted to Messrs. Clark and 

 Bathe in 1863. The first steam road roller used in the United States 

 was imported from England in 1868, and its first use was on the 

 United States arsenal grounds hi Philadelphia. 



The stone crusher has greatly reduced the labor of preparing broken 

 stone. It was the invention, in 1858, of Eli Whitney Blake, of New 

 Haven, Conn. He was a nephew of Eli Whitney, the inventor of the 

 cotton gin. Mr. Blake's crusher was used first in Central Park, New 

 York City, in crushing rock for concrete. In 1859 the city of Hart- 

 ford, Conn., purchased one of these crushers for use in the improve- 

 ment of its streets and roads. This was the first successful application 

 of mechanical power to breaking stone for road-building purposes. 



CRUSHER PLANT. 



Figure 1, represents a portable stone-crusher plant. A crusher 

 plant is indispensable in the construction of first-class broken-stone 

 roads, and if such work is to be done well and cheaply the plant must 

 be complete and conveniently arranged. 



Sometimes the crusher can be located so near the quarry that the 

 rock may be sent down grade in tramcars and delivered to the mouth 

 of the crusher by gravity, thus saving much hand labor. The crusher 

 should be provided with an elevator for delivering the broken stone 

 to the screen, which separates the material into proper sizes. The 

 screen should be in three sections. The first section usually contains 

 openings 1 inch in diameter. Through these openings the fragments 

 of ^tone known as "screenings" drop into a bin corresponding to 



