720 EXPERIMENT STATION EECORD. 



" It was further sliowu that uf amino acids as such only ti'aces are present, 

 and that such compounds are only obtainable after treating with hot concen- 

 trated hydrochloric acid ; 000 gm. of dry humic acid yielded the following decom- 

 position products: Alanin 2.30 gm., leucin 2.16, alanin+aminovalerianic acid 

 0.11, aminovalerianic acid 0.57, copper salt of active prolin 0.67, copper salt 

 of inactive prolin 0.5, aspartic acid 0.06, impure aspartic acid 2.16, glutamic 

 acid present, tyrosin trace, histidin trace, ammonia 1.0, copper salts of un- 

 known acids 30.3. Of course, these tiuantities show tlie niininium amount of 

 the yield, as a part of these substances are lost during the puritication process." 



Nitragin, O. Molina and C. Macias (AgrkuUor YYuvatan], 1 (1907), Xo. 10, 

 PI). l~jl)-l5S). — This article contains the instructions of the commission of agri- 

 cultural parasitology of Mexico regarding the use of this material, with a view 

 to testing it on a large scale by farnjers. 



Cereals and bacteria, W. B. Bottomley {Country Life {London], 22 (1907), 

 No. 560, i). .'/(ji), fig. 1). — This is a brief announcement of the isolation of nitro- 

 gen-fixing bacteria which increase the yield of barley, wheat, and oats when dis- 

 tributed in the soil on which these crops are grown. 



Purpose and plan of an experimental field for bacteriological investiga- 

 tions, W. KRUiiER (Landir. Jiihrl)., .36 {1907), Xo. 3, pp. 371-382). — A system 

 of experiments for this purpose as outlined for use in cooperative work by the 

 German Agricultural Society is briefly described. 



Soil fertility, M. Whitney, trans, by H. Fabre (Ann. Ecole Xat. A(jr. Mont- 

 pellier, n. so:. 7 (1907), No. 2, pp. 89-130). — A translation of Farmers' Bulletin 

 257 of this Department (E. S. R., 18, p. 119). 



The maintenance of fertility (Ohio Stn. Bui. J S3, pp. 190-228, figs. -{, 

 dgms. 2). — The experiments reported in this bulletin began in 1S07 and have 

 included laboratory, stable, and field investigations with manure from a large 

 number of growing and fattening steers, dairy cows, and sheep. 



T^he report deals with the amount and composition of manure produced by 

 different animals under varying conditions, the deterioration and preservation 

 of the manure, and its effectiveness as shown in field experiments with various 

 crops. 



In tlie experiments steers fed on a cemented floor iiroduced 3s.o lbs. of ex- 

 crement, exclusive of bedding (which averaged about 7 lbs. additional), per 

 1,000 lbs. live weight per day. Three-fourths of the nitrogen and phosphorus 

 and seven-eighths of the potassium given in the feed and bedding were recov- 

 ered in the manure thus produced. The quantity of manure produced by dairy 

 cows was considerably larger than that from fattening steers. Lambs fed 

 under shelter on an earth floor, on which the manure was permitted to ac- 

 cumulate, produced 20.86 lbs. of excrement, exclusive of bedding (which aver- 

 aged 3.20 lbs. additional), per day and per 1,000 lbs. of live weight. About 

 two-thirds of the nitrogen, four-fifths or more of the phosphorus, and nine-tenths 

 of the potassium contained in the feed and bedding were recovered in the 

 manure from lambs thus fed. 



" When manure was exposed for 3 months in an open barnyard during the 

 winter and early spring it lost nearly one-third of its total fertilizing value, 

 as shown by chemical analysis. When such manure was compared with fresh 

 manure in field experiments the ton of yard manure produced increase to the 

 value of $2.15, as a 10-year average, while the ton of fresh manure gave an 

 average increase of $2.06 for the same period, showing a loss in effectiveness 

 of 81 cts. per ton, or 27 per cent. 



" When either fresh or yard manure was reenforced with gyiisum or kainit 

 its effectiveness was decidedly increased, but when floats or acid phosphate 



