FIELD CROPS. 941 



and analyses of the silage gases obtained from them were made in connection with 

 these experiments, and the results are given in a table. An excess of residual gas 

 over what should be expected if only the residual nitrogen of the air originally in the 

 silo were present was found and its occurrence is discussed. That the air in the silo 

 becomes rarefied was demonstrated bv the development of a negative pressure in the 

 bottles which at times j)rodnced a suctional effect quite marked. In one experiment 

 silage exposed to the air did not mold, and lost in weight only 0.3 lb. or 0.4 per cent 

 from May 15 to September 18. This silage although appearing normal was less acid 

 than ordinary silage, and had a decidedly abnormal taste. Forcing fresh air tlirough 

 a silo did not injure the appearance of the .silage, but gave it a bad odor and made it 

 unpalatable. 



From the data obtained the author draws the following conclusions: 



"We know that during the early stages of the ensiling process, carbon dioxid is 

 given off in large volumes. Hydrogen is given off from normal clover silage in both 

 the earlier and later stages, and it is probably a constituent of the earlier gases from 

 normal corn silage but produced only in small quantities. Nitrogen, other than that 

 of the residual air, is likely to be proven to be a notable component of the gases from 

 normal silage at all times. AVater vapor and other volatile products escape with the 

 gases of normal silage at all times, but their quantitative relations have not been 

 sufficiently investigated to permit any statement as to how large the loss from these 

 sources may be. 



"Changes take place in normal silage which can not be measured liy either a loss 

 of weight or the escape of gaseous or volatile products, and these must be investigated 

 before the changes in feeding value due to the ensiling process can be estimated and 

 understood. The more loosely silage is packed in the silo and the larger the volume 

 of entangled air the greater will be the unavoidable losses. The more open and 

 porous the silo walls are, the larger will be the volume of air drawn into the silage 

 by suction and forced in by wind pressure and barometric changes. The larger 

 losses near the upper surface of the silage, and especially at the sides, are measurably 

 increased by what may be designated silage breathing. The loss from this source 

 could certainly be reduced and possibly to a notable extent by providing a metal 

 cover under the roof which, when the silo is filled and the doors closed, would leave 

 the silo nearly air tight. Such an arrangement would reduce the breathing and thus 

 lessen the loss." 



Growing alfalfa, W. C. Currie {Fan)i Sludents' Ret:, 6 {1901), Xo. 10, pp. 146, 

 147). — A note on growing alfalfa in the Platte River Valley in Nebraska. 



Studies on Boheniian barley, B. Pkoch.^zka {('eutbl. Agr. Chem., 30 {1901), 

 No. 10, pp. 695-699). — This article is a discussion of Bohemian barleys. It recom- 

 mends that in all breeding experiments the variability in plants and the power of 

 transmission of the derived forms be carefully considered. The different species of 

 barley are described and several varieties comjiared. 



The efiFects of the growth of berseem on the soil, G. P. Fo.\I)E.n {.Tour. Kliediv. 

 Agr. Sor. nnd School Agr., S {1901), Xo. .3, pp. 1.34-140, pis. -2). — This article discusses 

 mainly the value of leguminous crops for soil improvement, and points out especially 

 the adaptation of berseem for this purpose. 



Some facts on the maize crop, G. P. Fo.vdex {Jour. Klwdir. Agr. Soc. and School 

 Agr., 3 {1901), No. 3, ])p. 130-133). — This article is a popular discussion on corn cul- 

 ture in Egypt. 



History of cotton, (i. P. Fo.\J)EX {Jour. Khedir. Agr. Soc. and School Agr., 3 

 {1901), Xo. 4, pp. ns-lS.'i). — Historical notes on cotton culture. 



Flax culture in Argentina, (". D. Girol.v {Bol. Agr. y Ganaderia, 1 (1901), Xo. ,J, 

 pp. 7S-9-5]. — General directions and stati.«tics. 



Johnson grass, C. K. Bali, ( U. S. Dcpl. .\gr., Burran of I'lunl fnifnsiri/ linl. 11, 

 pj). .^2, fig. 1) . — This bulletin gives a description of .Johnson grass, an<l discus.ses its 



