790 EXPERIMENT STATION EECOBD. [Vol.38 



liness; comfort, and humanity in the convict camp are not inconsistent with 

 economy and efficiency in the work of the inmates." 



Progress reports of experim.ents in dust prevention and road preservation, 

 1916 {U. S. Dept. Agr. Bui. 586 (1918), pp. 78).— New experiments begun by 

 the Office of Public Roads and Rural Engineering during the year 1916 are 

 described. These included experiments on bituminous macadam and bitu- 

 minous gravel construction on the Ru.=;sel Road in Alexandria County, Va. ; 

 bituminous gravel concrete and earth-oil asphalt on the Alexandfia-Accotink 

 Road in Fairfax County, Va. ; and the bituminous surface treatment of a new 

 gravel road leading from Gum Spring to Mount Vernon in Fairfax County, Va. 

 In addition special experiments with corrugated metal culverts were initiated 

 on the Texas post road in Comal and Hays Counties, Tex. 



Supplementary reports on experiments previously reported (E. S. R., 36, p. 

 188) are also included on bituminous macadam and bituminous concrete on 

 Mount Vernon Avenue Road, Alexandria County, Va., 1915 ; bituminous surface 

 treatment on Falls Road, Montgomery County, Md., 1915 ; bituminous macadam 

 on Bradley Lane, Montgomery County, Md., 1915; bituminous concrete at 

 Washington, D. C, 1915; oil asphalt-coralline rock at Buena Vista, Fla., 1915; 

 oil a.sphalt-sand at Jupiter, Palm Beach County, Fla., 1915; bituminous sand 

 and oil-limestone mixing methods at We.st Palm Beach, Fla., 1915; sand- 

 asphalt at Ocala, Fla., 1915 ; oils, tar preparation, and calcium chlorid-coralline 

 rock at Lemon City, Fla., 1914; oil, tar, and oil asphalt-coralline rock at West 

 Palm Beach Fla., 1914; oil-coralline rock at Miami, Fla., 1913; bituminous 

 surface treatment on Rockville Pike, Montgomery County, Md., 1913; tar 

 preparation and oil surface treatment at Washington, D. C, 1912 ; bituminous 

 concrete, cement concrete, oil cement concrete, vitrified brick, and bituminous 

 surface treatment on concrete at Chevy Chase, Md., 1912; bitimiinous con- 

 struction and surface treatment at Chevy Chase, Md,, 1911; oil cenaent con- 

 crete, oil asphalt, and tar and fluxed native asphalt at Jamaica, N. Y., 1911; 

 oil asphalt gravel at Ames, Iowa, 1910; tar and oil preparations at Knoxville, 

 Tenn., 1910; slag, lime, waste sulphite liquor, and tar at Youngstown, Ohio, 

 1910; sand-clay at Dodge City, Garden City, Bucklin, and Ford, Kai^, 1908; 

 and Kentucky rock asphalt at* Bowling Green, Ky., 1907. 



Mechanical culture and draft animals, -H. de Lappakent (Jow. Agr. Prat^ 

 n. ser., SO (1917), No. 10, pp. 177, 178). — Data from French sources are given 

 on the cost of maintenance of horses, mules, and cattle 'as draft animals, it 

 being shown thaH; cattle can be maintained for about one-fourth, the expense 

 of horses and mules. The economic conclusion is drawn that the development 

 of mechanical culture should involve the raising of cattle for draft animals, 

 thus making a great reduction in the number of mules and horses actually 

 needed, particularly in regions where the use of cattle as draft animals is not 

 unusual. ^ , 



Review of mechanical cultivation, M. Ringelmann {Bui. Soe. Encour. 

 Indus. Nat. [Paris'], 116 {1917), I, No. 2, pp. S99-418, figs. 7).— This outlines the 

 duties of the French Service for soil cultivation, reviews recent mechanical 

 cultivation experiments in France, and describes French, English, and Ameri- 

 can medianical cultivating machinery. 



Tests of mechanical cultivation, J. Dissoubrat {Prog. Agr. et Vit. {Ed. 

 VEst-Centre), S7 {1916), Nos. 49, pp. 542-548; 50,' pp. .561-563) .—F.onr days' 

 plowing tests of five tractors on stony calcareous clay soil, tenacious calcareous 

 day, siliceous clay, and rocky calcareous clay soil are reported and discussed. 



Tests of mechanical cultivation, E. Zachakeayicz {Rap. Trav. Dir. Scrv. 

 Agr. [Dept. Vauclus^, Prance], 1915-16, pp. 786-199).— Tests of six French 

 tractors on deep and shallow plowing are reported. 



