RURAL ENGINEERING. 89 



body, $G,000; electric hoist, $250; horsepower spreader with rotary pump and 

 piping, $700 ; 500 gal, tar kettle, $300 ; double kerosene burner outfit, $200 ; and 

 tools and accessories, $50 ; total $7,500. 



Changes noted in a tar exposed to traflB.c and weathering when used in a 

 road surface, W. W. Crosry (Surveyor, Jfl {1012), Xo. 1055, pp. 526, 521). — 

 The results of tests of the carbon-free extract of portions of a coal-gas tar- 

 road surface, which had been exposed to weather and traffic for 3 years, are 

 reported. 



Among the changes noted, the lowering of the melting and initial boiling 

 points is very marked. The opinion is expressed that the distillation of bitumin- 

 ous compounds is materially affected by the presence of free carbon, and that 

 a secondary analysis should be made of all bituminous materials containing it 

 in appreciable amounts. 



Highway laws of the United States {Good Roads, n. aer., 3 {1912), No. IJf, 

 pp. 215-223). — Brief digests are given in this article of the laws affecting road 

 administration, construction, and maintenance in the several States. 



Concrete construction on the live-stock farm ( U. 8. Dept. Agr., Farmers^ 

 Bui. JjSl, pp. 32, figs. 2ff). — This bulletin deals with the construction of con- 

 crete feeding floors, manure pits and basins, and dipping vats. 



The advantages of a concrete feeding floor pointed out are cheapness, dura- 

 bility, sanitarj' qualities, saving of grain, labor, and manure, and neat appear- 

 ance. The essential details of construction of concrete feeding floors for cattle, 

 hogs, sheep, and poultry are discussed under the subheads of materials, location, 

 grading, drainage, necessary equipment, apportioning and mixing the concrete, 

 general method of construction, and curing. A short statement of cost is also 

 given. 



The wastefulness of the ordinary methods of manure storage is pointed out 

 and directions are given fo;- the proportioning of concrete and the general con- 

 struction of concrete manure basins and shallow manure pits. The important 

 points to be considered in the planning, construction, and care of concrete dip- 

 ping vats are also pointed out and discussed, and the construction details are 

 given. 



The action of alkali salts upon Portland cement, E. Burke and R. M. 

 PiNCKNEY {Jour. Indus, and Engin. Cliein., 3 {1911), Xo. 5, pp. 311-326). — Pre- 

 viously noted from another source (E. S. R., 25, p. 490). 



Practical barns in use on northwestern farms, S. K. Haugen et al. 

 {Farmer, 31 {1912), Xo. 16, pp. 58',, 58S-591, figs. 23).— Plans and descriptions 

 are given of barns as worked out and proved satisfactory by actual farm ex- 

 perience. 



Economy in sanitary bam construction, H. G. Lotter {Farmer, 31 {1912), 

 Xo. 16, p. 583, figs. 3). — The author describes economic methods of sanitary 

 cow barn construction, and discusses, as the main essentials of construction, 

 drainage, warmth, ventilation, light, and easy handling of feed and refuse. 



Cement silo construction, M. S. King {Cement and Engin. Xeics, 2 If {1912), 

 Xo. Jf, pp. 123^125). — The author points out the essential requirements of silos 

 and deals especially with masonry silos, discussing their lasting qualities and 

 such construction details as reenforcing, foundations, doors, and roofs. 



Open-air poultry houses for all climates, P. T. Woods {Chicago, 1912, pp. 

 86, pi. 1, figs. J,.'i). — Many types of open-air poultry houses are illustrated and 

 described. 



Electricity in agriculture and reference to central rural plants, H. Wallem 

 {Die Elektrizitat in der Landwirtschaft und deren Beziehungen zu Uberland- 

 zentralen. Diss. Tech. Hochschule Karlsruhe, 1910, pp. 1,6, figs. 21). — This 

 pamphlet deals with the use of electricity in the operation of agricultural 



