clxviii GENERAL SUMMARY OF SCIENTIFIC AND 



Dr. Mayer, of the University of Heidelberg, described ex- 

 periments on the absorptive power of leaves from ammonia, 

 from which it appeared that, contrary to the usual belief, 

 leguminous plants have no special facility for absorbing com- 

 bined atmospheric nitrogen. 



Dr. Von Wolff reported experiments on the effects of dif- 

 ferent amounts of phosphoric acid on the development of oat 

 plants grown in aqueous solutions. 



Besides the experiments here referred to, a large number 

 of investigations upon the nutrition of animals and plants, 

 and alliedsubjects, have been in progress in the German sta- 

 tions during the past year. Among the most important of 

 these researches are those upon the functions of the differ- 

 ent ingredients of food in animal nutrition, which are carried 

 on by means of the respiration apparatus. 



The sources of supply and the means of regulating the sale 

 of commercial fertilizers are subjects of ever-increasing in- 

 terest. Examinations of the deposits of Peruvian guano are 

 calculated to relieve the fears of those who were antici- 

 pating a speedy exhaustion of this article. 



The analyses of fertilizers, for the purpose of control of 

 the trade in these articles, are becoming year by year more 

 common, and their necessity better understood. In the ex- 

 periment station at Halle, in Germany, the number of these 

 analyses made annually has been increasing, until now it is 

 over one thousand. In the laboratory of Professor Voelcker, 

 of London, chemist of the Royal Agricultural Society of 

 England, where analyses of fertilizers are made for members 

 of the society and others, the amount of this work has grown 

 to such a decree that five or six assistant chemists are em- 

 ployed, who analyze about two thousand samples per year. 

 Professor Goessman, of the Massachusetts Agricultural Col- 

 lege, has been appointed inspector of fertilizers for that state. 

 His first report has appeared, and is a very valuable pam- 

 phlet upon the sources of supply and quality of the more 

 important fertilizing materials used in Massachusetts. The 

 Report for the Connecticut Board of Agriculture for 1873 

 contains the report of Professor Johnson on the analyses of 

 thirty-one fertilizers in common use in the state. A report 

 by Professor White on the analyses of fertilizers sold in 

 the State of Georgia is also worthy of mention. While the 



