RURAL ECONOMICS. 191 



Revolution counters on both engines and brakes showed a variation in belt 

 slippage of from 0.3 to 1.5 per cent. 



Gasoline tractors average<l close to 4 times as many horsepower hours per 

 unit of fuel as steam tractors, while kerosene tractors secured about 3 times 

 the fuel elficiency of the steam tractors. Excluding labor costs, however, the 

 steam tractors developed brake horsepower at a rough average of 20 per cent 

 less than the kerosene engines and every steamer defeated every gasoline 

 tractor on fuel cost per unit of brake power. This is considered a powerful 

 factor in retaining the moderate-sized steam tractor of from 50 to 75 b. h. p. 

 wherever threshing is of greater importance than plowing. 



Tables of data are appended showing the most important points of compari- 

 son, the total scores, and the relative standings. 



Mechanical cultivation in Germany, F. Bornemann and B. Donath {Die 

 Motorkultur in Deutschland. Berlin, 1913, pp. VIII +230, figs. 121).— This book, 

 based on the results of extended experiments, deals, in connection with mechan- 

 ical cultivation, with economy in the purchase of motor cultivating machinery 

 in Germany, and calls attention to the special points to be considered in the 

 judgment and choice of the various types for various classes of work. A chap- 

 ter on historical development is followed by a discussion of the relation of 

 mechanical cultivation to political and actual working economy. 



From a comparison of motor plows and scarifiers with steam tractor plows 

 it is concluded that the first two are best adapted to shallow surface cultivation 

 while the last is adapted to deep plowing. A comparison of mechanical and 

 electrical cultivation indicates that the first is on the whole the cheaper. An 

 exhaustive discussion of the mechanical details of motor cultivating machinery 

 calls particular attention to those points to be criticized in selecting or buying 

 machinery for various works. 



Descriptions of several single systems include both disk and moldboard 

 plows, among which, are (1) a plow and motor built together in a single 

 frame, (2) one in which they are in separate frames and connected by chains 

 or other coupling, (8) rope and windlass-drawn gang plows, (4) rotating 

 disk plows, and (5) motor scarifiers. 



In conclusion it is stated that so far no motor cultivators have been put 

 upon the market which are adapted to all conditions, and that their profitable 

 use is a matter depending on the good judgment of the owner. 



Various devices for drying the autumn forag-e harvest, Rahm {Illus. 

 Landic. Ztg., 32 {1912), Xo. 80, pp. 741, 7^2, figs. i7).— Several devices are 

 illustrated and described which are used in Germany, Sweden, and the hill lands 

 of other European countries. Among these are wooden rail frames, post and 

 wire frames, and posts fitted with teeth. 



RURAL ECONOMICS. 



Cooperation and nationality, G. W. Russell {DuUin, 1912, pp. 104). — The 

 various rural activities as they bear upon the social and economic life of a 

 nation and its rural population are discussed in this volume in chapters with 

 the following headings: The problem of rural life, past. and present conditions, 

 need for an agricultural revolution, the rise of agricultural cooperation, build- 

 ing up a new social order, town and country, organized communities and po- 

 litical life, the creation of citizens, women on the land, union of men and women 

 workers, farmers and the State, ideals of the new rural society, and life finding 

 its level. 



The legal status of farmers' cooperative associations {Internat. Inst. Agr. 

 [Romc^, Mo. Bui. Econ. and Soc. Intel, 4 {1913), No. 10, pp. 18-25).— This 



