820 EXPERIMENT STATION RECORD. [Vol. 38 



nitrate showed that plants grew vigorously when treated with small quantities 

 of lead. The maximum growth was obtained with 0.5 gnx of nitrate per liter 

 of nutritive solution. Not only did larger quantities affect the development of 

 the roots, but they also i-etarded that of the leaves. The same results were 

 obtained in this respect with all the experimental plants, rye, wheat, oats, 

 barley, maize, and peas. The difficulty of spreading the lead nitrate was over- 

 come by making it into a fine powder and mixing it well with the potash salt 

 or sodium nitrate used as manure. Manuring experiments with beets resulted 

 in a certain increase in yield of both roots and sugar which could be attributed 

 to the lead nitrate. Potatoes, on the other hand, proved vei*y sensitive to the 

 action of lead, which caused a decreased yield of tubers and starch." 



In experiments with wheat in sandy loam, " the addition of 44 lbs. of nitric 

 nitrogen to the basic manure increased the grain yield by 880 lbs. ; 56 per cent 

 of this nitrogen was assimilated. The addition of 9 lbs. of lead nitrate only in- 

 creased the grain yield by 187 lbs. as compared with tlie basic manure and only 

 21.5 per cent of the nitrogen was assimilated. The addition of 66 lbs. of nitric 

 nitrogen to the basic manure increased the grain yield by 1,320 lbs. and 82.3 per 

 cent of the nitrogen was assimilated. In this case the addition of 9 lbs. of lead 

 nitrate had a favorable effect on the grain yield, which it increased by 2,123 

 lbs. as compared with the basic manure. . . . 



" There is nothing against the practical use of lead nitrate and, so long as 

 the manufacturer can guarantie a uniform distribution of the lead, the mixing 

 of lead nitrate with potash salts and sodium nitrate on a commercial basis is 

 recommended." 



Commercial stocks of fertilizer and fertilizer materials (J7. S. Dcpt. Agr., 

 Office Sec. Circ. lOJf (1918), pp. 12, fiys. 5). — This circular presents statistical 

 information obtained through the AVar Emergency Fertilizer Survey of October 



1, 1917, regarding the stocks on hand and in transit ; the quantities under con- 

 tract or option for delivery before April 1, 1918 ; comparative figures based on 

 returns from concerns reporting for both 1916 and 1917 ; imports ; and produc- 

 tion of nitrate of soda, potash, sulphuric acid, sulphate of ammonia, slaughter- 

 house and garbage tankage, sulphur, foreign and domestic pyrites, acid and reck 

 phosphate, mixed fertilizers, cottonseed meal and cake, dried blood, raw and 

 steamed bone, fish scrap, cyanamid, and base goods. 



The returns for 1917 showed an increase over 1916 in commercial stocks of 

 potash, sulphate of ammonia, and acid and rock phosphate, while a marked 

 decrease was noted in the case of nitrate of soda, mixed fertilizers, dried blood, 

 slaughterhouse and garbage tankage, and to a less degree of sulphuric acid and 

 foreign and domestic sulphur and pyrites. 



Peat in 1916, J. S. Tuep (U. S. Geol. Survey, Min. Resoiirces U. S., 1916, pt. 



2, pp. 2S9, 290). — Statistics regarding the use of peat as fertilizer and fertilizer 

 filler, stock food, and litter in the United States during 1916 are given. Of the 

 total consumption of 55,548 short tons, 48,106 tons was used as fertilizer and 

 fertilizer filler, as compared with 38,304 tons in 1915. 



AGEICTJLTTJRAL EOT AIT?. 



Sig'nificance of colloidal chemistry in physiology, W. Cbocker (Trans. III. 

 Acad. ScL, S (1915), pp. 47-6S). — This paper deals with the colloidal nature of 

 living cells, general characteristics and water relations of cell colloids, diffusion 

 in a colloidal medium, enzyms and immunity bodies as colloids, some colloidal 

 phenomena of soils, and topics in colloidal chemistry and their bearing upon 

 physiology (as in aging seeds), giving a bibliography of the subject. 



