518 EXPERIMENT STATION RECORD. 



The amount of nitrogen fixed per gram of Beijerinck's mannit solution was 

 increased from 2.23 mg. to 10.3 mg. by addition of the iron solution. The form 

 of the iron was also found to have an important influence, there being a much 

 greater fixation of nitrogen with applications of iron in form of Thomas phos- 

 phate and of iron silicate, than with equal applications in the form of other 

 compounds of organic as well as of inorganic character. The beneficial effect 

 increased with the larger amounts of iron. 



The author states that although the exact nature of the action of the iron 

 has not been definitely determined, it would seem that the main process is one 

 in which the iron acts as a catalytic agent, changing the nitrogen of the air 

 to nitrite. In this form it is taken up by the bacteria, whereupon new nitrite 

 is formed, the process going on continually. * 



The influence of stall manure upon the bacterial flora of the soil, J. C. 

 Temple {Ccntbl. Bakt. [etc.], 2. Aht., S.'i {1912), No. 8-9, pp. 204-223) .—These 

 investigations have already been noted from another source (E. S. R., 26, p. 31). 



Earthworms and the fertility of the soil, C. Beauge (Jour. Agr. Prat., n. 

 ser., 23 (1912), Ko. 16, pp. 506, 5()7).— Investigations carried on by the British 

 Government in the valley of the White Nile in the Sudan indicate that the great 

 fertility of the soil of this valley is due in large part to the work of earthworms. 

 Observations are recorded from which it is estimated that the castings of 

 earthworms on these soils during the 6 months of the most active gi'owing 

 season of the year amounts to 239,580 lbs. per acre. The author reports similar 

 observations in Upper Egypt from which it is estimated that the castings in 

 this region amount to 58,785 lbs. during the 6 months. 



[Maintenance of soil fertility in China, Korea, and Japan], F. H. King 

 (In Farmers of Forty Centuries. Madison, Wis., 1911, pp. /X+4-}^, pi. 1, 

 figs. 21i8). — The results are here given of a study of the agricultural methods 

 and practices of these countries, particularly of the intensive methods of soil 

 management, developed by a people who with almost no fertilizer resources 

 except those of the farm, the home, and the town, have maintained the pro- 

 ductiveness of fields for more than 3,000 years, supporting a population of nearly 

 500,000,000 people upon an area smaller than the improved farm lands of the 

 United States. The secret of this success is shown to be utilization of the 

 products of the soil so that there shall be no waste of fertility. 



"Almost every foot of land is made to contribute material for food, fuel, or 

 fabric. Everything which can be made edible serves as food for man or 

 domestic animals. Whatever can not be eaten or worn is used for fuel. The 

 wastes of the body, of fuel, and of fabric worn beyond other use are taken back 

 to the field ; before doing so they are housed against waste from weather, com- 

 pounded with intelligence and forethought, and patiently labored with through 

 one, three, or even six months, to bring them into the most efficient form to 

 serve as manure for the soil or as feed for the crop." 



In Japan there were in 1907 " some 5,814.362 households of farmers tilling 

 15,201,969 acres and feeding 3,522,877 additional households, or 51,742.398 people. 

 This is an average of 3.4 people to the acre of cultivated land, each farmer's 

 household tilling an average of 2.6 acres. The lands yet to be reclaimed are 

 being put under cultivation rapidly, the amount improved in 1907 being 64.448 

 acres. If the new lands to be reclaimed can be made as productive as those 

 now in use there should be opportunity for an increase in population to the 

 extent of about 35,000,000 without changing the present ratio of 3.4 people to 

 the acre of cultivated land." 



In the author's opinion, the agriculture of the newer nations would be 

 greatly benefited by a careful consideration of the intensive methods of these 

 countries. 



