1910] BUEAL ENGINEERING. 495 



crested to a certain limit and then decreased witli increasing speed. By 

 steadily increasing tlie working depth in sand and loam soil under the same 

 working conditions the draft increased in approximate proportion to the depth 

 until an optimum draft with reference to cross section was reached, and 

 thereafter increased faster than the depth. Steadily increasing the width of 

 plowing produced results in draft similar to those produced by varying the 

 depth of plowing only in sand soil. 



The soils were artificially compressed. The plowing draft increased with 

 increasing compactness of a uniformly damp sand soil at a rate greater than 

 a proportional rate. The draft also increased with the increasing dampness 

 of a sand soil up to a certain limit and thereafter decreased. In a soil 

 dampened irregularly the draft increased with decreasing dampness. The 

 practical application of these methods and results to field conditions is also 

 discussed. 



Comparison of team and tractor for hauling gravel, O. L. Kipp (Municipal 

 Engin., 50 {1916), No. 4, pp. 138, 139).— Data, are presented from the gravel 

 checker's records on five team-hauling jobs totaling 22 miles of road gravelled 

 and 1 tractor-hauling job covering 3.6 miles of road gravelled, the gravel being 

 placed at the rate of 15 cu. yds. per 100-ft. station on each job. A 36-60 horse- 

 power caterpillar gas tractor and a train of 3.5-yd. reversible spreader wagons 

 with a 50-yd. storage bin and a belt conveyor loader were used. 



" It would appear that the cost of hauling by tractor was considerably less 

 than by teams. The advantage in favor of the tractor would have been 

 greater had there been more power available. A 40-80 tractor would have made 

 a much better showing. Another factor cutting down the capacity of the 

 train was the inability of the loading equipment to supply gravel fast 

 enough. ... It would appear that efficiency in team hauling and con- 

 sequent low cost is largely dependent upon, and might easily be secured by, 

 obtaining the maximum efficiency in loading." Features in favor of tractor 

 hauling were that, first, by applying the gravel in two courses with a tractor the 

 gravel is rolled without additional cost and the road is ready for travel as 

 soon as the gravel is applied, instead of a month or more later, as with teams ; 

 and second, by loading into a bin, thence to wagons, and thence to the road, 

 an efficient mix of the materials is obtained. 



Knots and splices, I. D. Charlton {Wash. Agr., 9 {1916), No. 7, pp. 191- 

 195, figs. 4)- — A few of the more simple and common knots used in farm work 

 with rope are described and illustrated. 



Barns for Wisconsin dairy farms, F. M. White and C. I. Geiffith {Wis- 

 consin Sta. Bui. 266 {1916), pp. 32, figs. 25).— This bulletin discusses the gen- 

 eral requirements of and the more important factors to be considered in the 

 construction of barns for dairy farms to meet Wisconsin conditions and de- 

 scribes three general-purpose barns, one single story dairy barn, and a pioneer 

 barn. Rectangular barns are considered more satisfactory than round ones, 

 and gambrel roofs are preferred to gable roofs. 



Construction of fresh air brooders, H. E. Upton {Brit. Columbia Dept. Agr., 

 Live-stock Branch, Circ. 3, 2. ed. {1913), pp. 6, figs. 6).— This structure is 

 briefly described and illustrated. 



Winter storage of potatoes. E. Schaffnit {Ztschr. Landw. Kammer Braun- 

 schiceig, 84 {1915), No. 28, pp. 245-249, figs. 2). — In outlining the conditions for 

 proper winter storage of potatoes, it is pointed out that the potatoes must be 

 absolutely protected from frost, and must, at the same time, be kept dry and 

 not too warm, as both heat and dampness are favorable to the rotting of 

 potatoes. 



