89'2 EXPJERIMENT STATION RECORD. [Vol. 43 



Lower valuos of tension must be used for inclined or vertical drives or if the 

 distance between pulley centers is unduly short. These belts are said to be 

 particularly suitable for slow drives, large pulleys, and long spans, and can be 

 substituted directly for leather belts of the same width and will transmit con- 

 siderably more power than leather. However, they lack the elasticity of 

 leather. 



EflPeots of oils, s^'^asos, and deoree of tannage on the physical properties 

 of russet harness leather, R. C. Bowker and J. B. Churchill ({/. -S. Dept. 

 Com., Bur. Standards Technol. Paper 160 {1920), pp. 18. figs. 19). — Studies on 

 the effects of the amount and kind of stuffing content and on the degree of 

 tannage on the physical properties of harness leather are reported. Russet 

 harness leather was u.sed. 



It was found that the amount of stuffing content affects the tensile strength 

 of the leather and that there is a point beyond which the amount of stuffing 

 content used does not add to the strength and may actually serve to decrease it. 

 The tensile strength was found to be greater for leather tanned a short time 

 than for leather given a long-time tannage, and the longer-time tannage pro- 

 duced leather more resistant to shear when used with a buckle. 



Stuffing with a mixture of 50 per cent Breton mineral oil and 50 per cent 

 tallow did not affect the physical properties of new leather in a manner differ- 

 ent from that of a mixture of 50 per cent cod oil and 50 per cent tallow. 



Notes on power farming, R. W. Lohman (Jour. Soc. Automotive Engin., 7 

 {1920), No. 2. pp. 160-174, 185, figs. 37). — Data on some of the methods and ap- 

 paratus which can be used to advantage in large-scale farming operations are 

 reported, together with numerous illustrations. These include especially dif- 

 ferent types of tillage, traction, and harvesting machinery. 



The cultivation of cereals and mechanical cultivators, L. Malpeaux {Vie 

 Agr. et Rurale, 9 {1920), No. 20, pp. 3^0-346, figs. 4).— Hoes, harrows, rollers, 

 and cultivators for the cultivation of cereals and truck crops are described, 

 and evidence as to the importance of their proper use in increasing crop yields 

 is presented. 



List of farm building plans {Iowa State Col. Agr. Ext. Bui. S3 {1919), 4 

 rev., pp. 8, fig. 1). — This is the fourth revision of this bulletin. 



Farm building ventilation, R. L. Patty {S. Dak. Agr. Col. Ext. Circ. SI 

 {1920), pp. 12, figs. 11). — Practical information on the installation of ventila- 

 tion systems in dairy and stock bams to properly meet South Dakota conditions 

 is given. 



Buildings for small holders: Experiments in adaptation, S. D. Meadows 

 {Jour. Min. Agr. [London], 27 {1920), No. 5, pp. 1,67-478, pi. 1, figs. 6).— -Plan 

 drawings of houses for small farms in England are presented and discussed. 



Small portable granary, M. R. Bentley {Okla.' Agr. Col. Ext. Circ. 119 

 (1920), pp. [4], figs. 3). — A small portable frame granary adapted to Oklahoma 

 conditions is described and illustrated. 



Design of circular reinforced concrete bins, W. W. Hay (Concrete [De- 

 troit], 17 (1920), No. 3, pp. 73-76, figs. 7).— Formulas and graphic data on the 

 design of circular reinforced concrete bins for the storage of grain are given. 



The Department of Agriculture cold storage plant, L. A. Hawkins (Better 

 Fruit, 14 (1920), No. 10, pp. 10, 36, figs. 2).— This cold storage plant for fruit 

 and vegetables is described and illustrated. 



Housing farm poultry, A. G. Philips (Indiana Sta. Circ. 98 (1920), pp. 22, 

 figs. 22).— The principles underlying pi-actical poultry house building are ex- 

 plained and illustrated with drawings, and working plans are given for model 

 houses to care for 100 and 150 fowls, together with poultry -house equipment, 

 Including indoor and outdoor feed hoppers. 



