1028 EXPERIMENT STATION RECORD. 



The pots were placed in porcelain saucers and the water c'ontent of the soil was 

 maintained at about 25 per cent of the water capacity of the soils by addition from 

 below. At the end of the period the nitrites and nitrates in the soil were ob- 

 tained for determination as follows: "One hundred grams of soil were shaken in a 

 2-liter bottle, provided with a stopper, with 1 liter of distilled water. After shaking 

 for 5 minutes the liquid holding the nitrites and nitrates in solution was filtered, 

 about a gram of freshly precipitated and washed aluminum cream added to the fil- 

 trate and the latter shaken. It was then filtered again, 100 cc, representing one- 

 tenth of the nitrates held in solution, carefully measured off for the determination 

 of nitrates, and 100 cc. for the determination of nitrites." The influence of varying 

 amounts of common salt and of sulphur, and of stirring the soil, on the nitrification 

 of ammonium sulphate was studied in the pot experiments. In the experiments in 

 flasks the influence of varying amounts of water and of sodium chlorid, ferrous sul- 

 phate, calcium carbonate and sulphate, and large quantities of organic matter was 

 studied. The results obtained with the pots were inconclusive. In the experiments 

 in flasks it was found that with amounts of water varying from 8 to 12 cc. per 100 gm. 

 soil there was little difference in the rate of nitrification. "There was a distinct 

 diminution in the amount of nitrates produced as the amount of salt was increased, 

 still the differences were not very great, and from this experiment we must conclude 

 that quantities of salt up to 0.1 per cent, or 3,500 lbs. to the acre, while they retard 

 nitrification, do not stop it entirely." 



Ferrous sulphate in amounts varying from 10 to 100 mg. per 100 gm. of soil appar- 

 ently had little effect. " Where equivalent amounts of gypsum were used the nitri- 

 ficatit)n was, on the whole, fairly uniform, and slighter than in the flasks where 

 calcium carbonate was used. ... It appears that more nitrate was formed where 1 

 per cent of organic matter was present than where only 0.5 per cent was present." 



The life of the soil, C. Bauvekd (Jour.Soc. Agr. Suisse Romande, 43 {1902), No. 1, 

 pp. 17-20). — A brief review of an article by Chuard on this subject. 



On the emission and absorbtion of heat and their importance in relation to 

 the temperature of the earth's surface, N. Ekholm [Meteor. Ztscltr. [17e*t»a], 19 

 {190;?), Xo. l,pp. 1-26, fiij. 1). 



The adaptation of seeds to soil, 8. Castex {Bui. Ayr. Ahjerle el Tiuiisie, S {1902), 

 No. 5, pp. 121-124). — A brief discussion of the influence of the chemical properties 

 of the soil on the seed and its offspring. 



FERTILIZERS. 



Contribution on the treatment of barnyard manure with absorbents to pre- 

 vent the loss of nitrogen in form of ammonia compounds, H. D. Haskins 



{Mossadm.^eilsiSta. B)iL 81, pji. 17, IS). — Experiments to determine the relative absorb- 

 tive power for ammonia of magnesium sulphate (kieserite) , potassium-magnesium sul- 

 phate, kainit, potassium sulphate, and calcium sulphate are referred to. Although 

 the results, "in all probal)ility, do not re]>resent the actual nitrogen al)sorption power 

 of the chemicals as used in ordinary farm practice," they show that calcium sulphate 

 (gypsum) possesses the lowest absorptive capacity for anunonia of any of the materials 

 tested, the results with magnesium sulphate being highest in this respect. 



Permanence of manure, T. Jamiesox (Proc. Agr. Re.^earch Assoc. [Al/erdeenshire}, 

 1901, pp. 26-42, dgms. 6). — A summary of 17 years' experiments undertaken for the 

 purpose of securing "precise and reliable information upon the relative permanence 

 of different forms of manure" to be used in determining the compensation for unex- 

 hausted manure under the "Agricultural Holdings Act." The fertilizers used were 

 various forms of bone, superphosphate, coprolite, and sodium and potassium nitrates. 

 The results showed that by the fifth year the fertilizers had become practically 



