IV PREFACE. 



made up largely from the " Anleitung zur Quant itativen 

 Chemischen Analyse, von Dr. C. R. Fresenius, 5te 



Auflage, 1866." 



Concerning late improvements in methods of analysis, 

 the Zeitschrift far Analytische Chemie, by the same au- 

 thority, has been frequently consulted. 



The scheme of qualitative analysis has worked well in 

 my own hands, and with my own students, but, neverthe- 

 less, I would have preferred to give it a more careful 

 trial before publishing it. 



Valuable assistance in testing this and other methods 

 of analysis has been received from Mr. T. B. Comstock, 

 while a student in my laboratory. 



The use of the old system of atomic weights, and of 

 the old nomenclature, would doubtless have made the 

 book more simple to the majority of students at first, but, 

 nevertheless, it seemed more expedient to follow the com- 

 mon usage in the best recent works on chemistry. The 

 same may be said in regard to the use of the centigrade 

 thermometer and the metric system of weights and 

 measures. 



Although the work lias been somewhat hastily prepared 

 to meet a pressing want in my own laboratory, I trust it 

 may yet be found to answer a good purpose in other lab- 

 oratories where agricultural chemistry is made a specialty. 



G. C. C. 



Cornell University, College of ) 

 Agriculture, August, 1869. f 



