18 



which facts and thoughts were formerly recorded, with 

 the marvelous product of the steam printing press, and 

 your wonder will be not that the ancients knew so little, 

 but that, with such imperfect means, they learned so 

 much; and you will readily acknowledge that not until 

 the discovery of the art of printing was it possible to get 

 together and compile a grand record of facts and ex- 

 periments, under different climates, at different altitudes, 

 in different soils, and under a multitude of varying con- 

 ditions, from which the man of science might deduce 

 general agricultural truths, and without which his 

 efforts would be comparatively vain. 



I have thus very briefly and imperfectly remarked upon 

 some of the reasons for the slow growth of agricultural 

 knowledge. But there is one of them which I have only 

 mentioned, about which a word, at least, should be said. 

 " Chemistry," says the Encyclopaedia Brittanica, " as a 

 regular branch of natural science, is of comparatively re- 

 cent origin, and can hardly be said to date from an ear- 

 lier period than the latter third of the past century. * * 

 From the very nature of chemistry it was impossible that 

 it should take a truly scientific form until the balance 

 was applied to it," which was first done by Lavoisier a 

 little more than one hundred years ago. But, in the 

 opinion of many of the ablest writers on the subject, 

 there cannot be, without the application of chemistry, 

 a true and perfect scientific agriculture ; and hence Ag- 

 ricultural Chemistry forms a part of the regular course 

 of instruction in all schools in Europe and America, in- 

 stituted for the purpose of promoting agricultural knowl- 

 edge. And here it may be well to notice an objection, 

 which though often made and often answered, is yet fre- 

 quently repeated and perhaps will ever be. 



How, says one, can a farmer, engaged from youth to 

 old age in manual labor on his farm, acquire this scien- 

 tific knowledge, so much vaunted and said to be so ne- 



