GERMAN AGRICULTURAL EXPERIMENT .STATIONS. 109 



The control work in dairy lines extends in various directions. Where 

 numerous fanners supply milk to a creamery for butter making, it is 

 obvious that every farmer should be paid on the basis of the fat content 

 of the milk furnished by him. Consequently the payment for milk 

 according to its fat content has become quite general and the majority 

 of creameries, for instance, in Schleswig-Holstein and the Prussian 

 Province of Saxony, have their milk tested for fat regularly at the dairy 

 experiment stations or dairy divisions. For this purpose each creamery 

 on certain days takes small samples of the milk brought by each patron 

 and sends these samples to the experiment station for analysis. 



The dairy division of the experiment station at Halle made in this 

 way some 20,000 analyses of milk for fat during the past year, and the 

 number will probably increase to 30,000 the present year. The test is 

 made by Wollny's refractrometer method, which has been found to be 

 the best for examination on a large scale. 



The examination of samples of butter for adulteration, etc. also 

 naturally falls to the dairy experiment station. As this dairy work lias 

 as yet assumed considerable proportions in only a few States in Ger- 

 many, it is safe to predict that t lie near future will bring ;i great in- 

 crease in the work required of the experiment stations, which in the 

 nature of the case they can not neglect to take up. 



STUDIES OF Till: FERTILIZER REQUIREMENTS OF THE SOIL. 



The agricultural experiment stations must by their analytical icorlc 

 determine for the farmer the condition of his soil as to the fertilizing 

 ingredients il contains <<n<l its fertilizer requirements. 



It was a long time before the agricultural experiment stations could 

 do work in this held which was directly beneficial. It was first neces- 

 sary to settle many preliminary questions before advice could be given 

 with some degree of certainty as to the result. For a time too much 

 was expected of the chemical examination and too great stress was laid 

 on the composition of the soil. It is true that the productiveness of 

 the soil depends upon the presence of certain quantities of definite con- 

 stituents, which are determined by chemical analysis, but without cer- 

 tain physical properties a soil with the best conditions as to fertilizer 

 constituents cannot be relied upon to show satisfactory productiveness. 

 Consequently, it very soon became necessary for the agricultural 

 experiment stations to elaborate methods for the physical examination 

 of soils as well as for chemical analysis; and on this problem the experi- 

 ment stations are still industriously working to day. 



It has long been known that the physical properties of cultivated 

 soils are of -equal importance with the chemical composition, and no agri- 

 cultural chemist would to day take exception to this. Often chemical and 

 physical problems are closely connected with each other. An example 

 of this is the lime question, which is at present the important question 

 relating to soils. In this very matter one-sided chemical investigation 



