ggg EXPERIMENT STATION EECOED. 



native asphalt in 1911; at New York, N. T., and Ridgewood, N. J., with oil- 

 cement concrete in 1910; at Boise, Idaho, with oil-gravel macadam in 1910; at 

 Ames, Iowa, with oil-asphalt gravel in 1910; at Knoxville, Tenn., with tar and 

 oil preparations in 1910; at Yoiingstown, Ohio, with slag, slag and lime, slag 

 and waste sulphite liquor preparation, and slag and tar in 1909; at Newton, 

 Mass., with asphaltic preparations, tar preparations, residual oil, and molasses- 

 oil-lime in 1908; at Garden City, Dodge City, Bucklin, and Ford, Kans., with 

 sand-clay in 1908 ; and at Bowling Green, Ky., with Kentucky rock asphalt in 

 1907 are also included. 



Proceedings of good roads institute held at University of North Carolina, 

 March 17-19, 1914 (N. C. Geol. and Econ. Survey, Econ. Paper 39 (1914), 

 pp. Ill, pis. If, figs. 15). — This report includes the following special articles: 

 Road Surveying and Mapping, by T. F. Hickerson ; The Use of the Abney Hand 

 Level, by T. F. Ilickerson ; Economics of Road Construction, by W. S. Fallis ; 

 Sand Clay and Topsoil Roads the Economic Roads for NQrth Carolina, by J. H. 

 Pratt ; Natural Sand Clays in the North Carolina Piedmont Belt, by J. E. Smith ; 

 Dirt Roads, by J. H. Pratt ; Drainage of Roads, by T. F. Hickerson ; County 

 Highway Bridges, by J. M. Ambler ; Culverts, by R. T. Brown ; Road Machinery 

 Required in County Road Construction, by N. C. Hughes, jr. ; Road Surfacing 

 Materials in North Carolina, by C. Cobb ; and Lignin Liquor as a Binder for 

 Macadam, Gravel, and Sand-clay Roads, by G. N. Moore. 



Steam as the by-product of internal combustion engines, J. B. Meriam 

 (Gas Engine, 16 (1914), No. 11, pp. 704-709, figs. 6).— The author shows by dis- 

 cussion and experiment that if an inclosed cooling system is used and only 

 steam is allowed to escape, all of the water used must eventually be turned into 

 steam. The total heat units of the fuel lost to the water jackets are fully 

 recovered and restored to the steam. In tests of such a system no difficulty or 

 detrimental effects were experienced when operating the engine at maximum 

 load with the jackets under full steam pressure and temperature. "Another 

 marked advantage in this process is found in the fact that the thermal efficiency 

 of the engine is improved so that the fuel consumed is at least 2 per cent less 

 at maximum load and fully 15 per cent less at one-foui-tli load." 



Increasing output of gas engines {Poicer, 40 {1914), No. 10, pp. 340, 341, 

 figs. 4)- — A method is described for increasing the output of gas engines, in 

 which the burnt gases are first scavenged and tlie working charge then admitted 

 under pressure, thus increasing the weight of the charge and consequently rais- 

 ing the mean effective pressure. 



Gas-engine valve setting, G. W. MtJENCH (Poicer, 40 (1914), No. 15, pp. 

 547, 54s, fig. 1). — This pai>er discusses the causes leading to altered valve 

 timing and gives simple directions for the proper resetting of the valve gear. 



Oil engines for pump irrigation and the cost of pumping, G. E. P. Smith 

 (Arizona Sta. Bui. 74 (1915), pp. 379-450, pis. 4, figs. i6).— This bulletin de- 

 scribes fuel oils and their tests and oil engines of the Diesel, modified gasoline 

 engine, and hot-ball groups, reports tests of the last two types as to fuel economy, 

 capacity, speed regulation, and power development, discusses oil engine charac- 

 teristics based on the tests reported, and gives data on the cost of pumping for 

 irrigation. 



It is pointed out that ga.soline is too expensive a fuel for pumping engines in 

 Arizona. Cheap distillates of from 39 to 44° Baume with low flash point are 

 deemed the most advisable to use at the present time, these being preferably 

 purchased in carload lots. 



It is thought that Diesel engines are not adapted to farm conditions. " Pour- 

 cycle gasoline engines with electric ignition and suction fuel feed can be modified 

 to burn heavier distillates successfully by feeding water with the charge. 



