INTRODUCTION. 23 
perfect, because our knowledge of facts is incomplete, our 
mental insight weak, and our judgment fallible. But the 
scientific theory which is framed by the contributions of a 
multitude of earnest thinkers and workers, among wkom 
are likely to be the most gifted intellects and most skillftl 
hands, is, in these days, to a great extent worthy of the 
Divine truth in nature, of which it is the completest hu- 
man conception and expression. 
Science employs, in effecting its progress, essentially the 
same methods that are used by merely practical men. 
Its success is commonly more rapid and brilliant, because 
its instruments of observation are finer and more skillfully 
handled; because it experiments more industriously and 
variedly, thus commanding a wider and more fruitful ex- 
perience; because it usually brings a more cultivated im- 
agination and a more disciplined judgment to bear upon 
its work. The devotion of a life to discovery or invention 
is sure to yield greater results than a desultory applica- 
tion made in the intervals of other absorbing pursuits. It 
is then for the interest of the farmer to avail himself of 
the labors of the man of science, when the latter is willing 
to inform himself in the details of practice, so as rightly 
to comprehend the questions which press for a solution. 
It is characteristic of our time that large associations of practical 
agriculturists have recognized the immediate pecuniary advantage to be 
derived from the application of science to their art. This was first done 
at Edinburgh, in 1848, by the establishment of the ‘‘ Agricultural Chem- 
istry Association of Scotland.” 
This organization limited itself to a duration of five years. At the 
expiration of that time, its labors, which had been ably conducted by 
Prof. James F. W. Johnston, were assumed by the Highland and Agri- 
cultural Society of Scotland, and have been prosecuted up to the present 
day by Dr. Anderson. The Royal Ag’1Soc. of England began to employ a 
consulting chemist, Dr. Lyon Playfair, in 1848; and since 1848 most 
valuable investigations, by Prof. Way and Dr. Velcker, have regularly 
appeared in its journal. Other British Ag’l Societies have followed thess 
examples with more or less effect. 
It is, however, in Germany that the most extensive and well-organized 
efforts have been made by associations of agriculturists to help their 
