933 



congresses is Iieitig considered. At present it is believed that an international con- 

 gress of sugar chemists will be held in Brussels in the s])ring of 1893. 



Report of the Darmstadt Statiox for 1891. — Prof. Paul Wagner, the director 

 of the station, reports the examination of 3,010 samples during 1891. Of these, 1,956 

 were fertilizing materials, 603 feeding stuffs, 325 seeds, and the remaining 126 mis- 

 cellaneous. Serious cases of fraud and adulteration in the sale of fertilizers were 

 noticed. Farmers are warned especially against jiurchasing Thomas slag from other 

 than reliable firms, as adulteration of this phosphate is unusually common. Under 

 the name of Thomas slag a material was sold closely resembling it in appearance, 

 but believed to be "pjiddle slag." Although this contained phosphoric acid, none 

 of it was in available form. Rei)eated attempts to render mineral phosphates 

 more easily available by glowing and to give them the appearance and action of 

 Thomas slag have usually resulted unsatisfactorily, although in one or two cases 

 products have been secured of equal value with Thomas slag. The process was, 

 however, found to be too expensive. 



In addition to some 1,200 pot and plant experiments which Mere made during the 

 year, a series of field experiments on a larger scale was commenced to study the 

 application in practice of the theories suggested by the pot experiments. 



Experiments have also been begun to compare the crude with the more concen- 

 trated agricultural chemicals, such as potassium phosphate, potassium nitrate, 

 ammonium nitrate, and ammonium phosphate, which are now being extensively 

 manufactiired for fertilizing purposes. A report on these and ou experiments in 

 manuring fruits are promised in the next annual reiiort. 



