322 EXPERIMENT STATION RECORD. 



The electro-chemical problem of nitrogen fixation, P. A. Guye {Monit. ScL, 

 k. ser., 21 (1907), I, pp. 225-236; ahs. in Chem. ZentbL, 1907, I, No. 23, p. 

 1647). — The general problem is stated and the Frank-Caro and electro-chemical 

 processes are discussed. 



The author believes that the problem of electro-chemical preparation of 

 nitric acid will only be completely solved when methods of liquefaction of the 

 air and the separation of its constituents have been perfected. The solution 

 of the problem also depends upon the production of cheap electrical power from 

 coal. The author estimates the present cost per pound of production of nitric 

 nitrogen to be 11.4 cts. in form of lime niter, and 10.5 cts. in form of nitric acid 

 assuming the cost of power to be $10 per kilowatt year. His estimate of the 

 cost per pound of nitrogen in the form of cyanamid varies from 12 to 14 cts. 



The fixation of the nitrogen of the air and lime niter, A. Rigaut (Rev. f>ci. 

 [Parish, 5. ser., 7 (1907), No. 25, pp. 778-780).— The cost of the production of 

 nitrates from the nitrogen of the air by electrical processes and the agricultural 

 value of the product so obtained are briefly discussed mainly on the basis of a 

 recent article by Guye noted above. 



The use of feldspathic rocks as fei'tilizers, A. S. Cushman (V. 8. Dept. 

 Agr., Bur. Plant Indus. Bui. 104, PP- 32). — The importance of potash as a con- 

 stituent of fertilizers, the occurrence of potash in nature, the availability of 

 the potash of ground rock, the effect of fineness of grinding, cost of ground feld- 

 spar, and extraction of potash from ground feldspar (E. S. R., 18, p. 717) are 

 discussed and the literature of the subject I'eviewed. A limited number of 

 greenhouse and field experiments in which fine ground feldspar was used jon 

 tobacco are briefly reported. 



The general conclusion reached is that " systematic and long-continued ex- 

 perimentation is the only possible method of obtaining conclusive information 

 on the subject. The evidence so far o^^ained appears to indicate that under 

 certain conditions and with certain croijs feldspar can be made useful if it is 

 ground sufliciently fine. On the other hand, it is highly probable that under 

 other conditions the addition of ground feldspar to the land would be a useless 

 waste of money. At the present stage of the investigation it would be ex- 

 tremely unwise for anyone to attempt to use ground rock, except on an experi- 

 mental scale that would not entail great financial loss. . . . 



" It is extremely unlikely that ground rock will ever entirely displace the use 

 of potash salts, for its availability must inevitably depend upon many modify- 

 ing conditions, such as the nature of the soil, the amount of moisture present, 

 the character of the other fertilizers used, and the varying root action of differ- 

 ent crops. With tobacco the results so far obtained have been encouraging, but 

 it is possible that this plant, which is a voracious feeder, can make use of the 

 potash in fine-ground feldspar to a greater extent than other fast-growing crops, 

 such as potatoes and the cereals, some of which mature in practically GO days 

 and must therefore find their i>lant food in a highly available condition." 



Influence of calcium carbonate on the development of yellow lupine in 

 podzol (Bleisand) soil, A. F. Khandurin (Zhur. Opuitn. Agron. [Russ. Jaw. 

 Expt. Landw.], 7 (1906), No. 6, pp. 667-676, figs. 10).— The author found that 

 calcium carbonate is useful for the development of lupines in the early stages 

 of their growth but injurious at later stages. The carbonate interferes with 

 the full development of the root tubercles, whose function in supplying nitrogen 

 is of greater importance "in the later stages of the growth of the lupines. — p. 

 fireman. 



Analyses of commercial fertilizers, B. L. Hartwell et al. (Rhode Island 

 Sta. Bui. 122, pp. 177-187). — "This bulletin contains the analyses of such 

 potato and vegetable fertilizers found on sale in the State in the spring of 1907 



