412 



SCIENCE 



[N. S. Vol. XXV. No. 637 



The Work of the Association of Official 

 Agricultural Chemists on the Analysis 

 of Tanning Materials: F. P. Veitch. 



Soil Acidity m its Relation to Lack of 



Availalle Phosphates: A. R. Whitson 



and C. W. Stoddart. 



Experience has shown that a direct de- 

 termination of the amount of essential ele- 

 ments present in a soil does not show its 

 fertility, since it does not consider the de- 

 gree of availability. It is unquestionably 

 true, however, that the processes by which 

 these elements become available are chem- 

 ical, and depend upon the conditions exist- 

 ing in the soil. A determination of the 

 conditions which influence the rate at which 

 the elements become available and which 

 affect the accumulation of the available 

 material would enable us to diagnose the 

 needs of the soil more quickly and surely 

 than by direct field and pot experiments. 

 Investigations of the fertilizer require- 

 ments of soils during the past two or three 

 years have shown that whenever a soil is 

 acid it needs phosphates. 



Careful tests were made on nineteen 

 soils, thirteen of them acid. All acid soils 

 showed by field or plant-house tests the 

 need of a phosphate fertilizer. Three of 

 the soils, not acid, showed the need of phos- 

 phates, although rather slight in one case. 

 The soils tested were mostly clays from as 

 many different localities in Wisconsin as 

 possible. 



Although there is phosphoric acid pres- 

 ent in these soils in sufficient quantity for 

 many crops it is unavailable, and hence the 

 soils need phosphate fertilizers. The soil 

 acids probably act upon the readily avail- 

 able phosphates, such as the calcium phos- 

 phates, at a more rapid rate than the nor- 

 mal, neutral or alkaline soil moisture, and 

 when once in solution these phosphates are 

 readily washed out by heavy rains, or are 

 fixed by iron and aluminium hydroxides— 



that is, are precipitated and rendered un- 

 available as insoluble iron and aluminium 

 phosphates. When there is sufficient lime 

 in the soil to maintain the phosphoric acid 

 in the form of calcium phosphates, the 

 plant is able to obtain enough phosphorus 

 for its use, since calcium phosphate is 

 soluble enough to supply the needs of a 

 growing crop. 



A Quick Method for the Determination of 

 Moisture in Grain: E. Brown and J. W. 



T. DUVEL. 



By the use of the method and the ap- 

 paratus outlined in this paper, the moisture 

 content of any sample of grain or similar 

 material, can be determined in from twenty 

 to thirty minutes. The method consists 

 primarily in heating the weighed sample 

 of grain in about 100 c.e. of hydrocarbon 

 oil, the moisture expelled being afterwards 

 condensed and measured in a graduated 

 flask reading to tenths per cent. A special 

 apparatus is required for this method of 

 making moisture determinations. 



In the afternoon a number of the chem- 

 ists were given a luncheon at the works of 

 the Schultz Mineral Water Company, after 

 which there was a choice of excursions to 

 the Gas Works, the Pacific Borax Works 

 and the New Jersey Zinc Works at Newark. 

 The same evening there was a subscription 

 dinner at the Waldorf Hotel. 



On Saturday morning the annual meet- 

 ing of the American Chemical Society was 

 held. The secretary reported that the 

 membership was now 3,079, a net gain 'of 

 160 over last year. There are, besides, 187 

 members who have been elected, but who 

 have not yet qualified. Of the latter, 150 

 had applied during the last two months. 

 New local sections have been established in 

 Minnesota, Indiana, Louisiana and at the 

 University of Illinois. 



The report of the treasurer showed that 



