6 WORCESTER COUNTY HORTICULTURAL SOCIETY. [1881. 



is danger that tlie advantage of chemistry in agricnlture will be 

 under-estimated. 



Dr. Playfair's translation of Liebig's great and useful work — 

 Chemistry in its Relations to Agricnlture and Physiology— awak- 

 ened many hopes that were destined to disappointment. In this 

 country, the New York Ti-ibune following the suggestions of 

 Liebig's book gave too much countenance in its invahiable agri- 

 cultural department to the notion tliat a farmer can tell by a 

 chemical analysis of his soil just how to treat his crops. 



At this time, seventy years since the era of Liebig's Chemistr}'', 

 all opinions seem to agree that chemistry is a valuable auxiliary 

 to agriculture, but cannot claim to be its leader. As one wise 

 man called theology " sanctified common sense " so good agri- 

 culture is instructed common sense. But chemistry has done 

 some service to agriculture and will yet do much more. The 

 nature of fertilizers has been effectively investigated, and more 

 recently that of feeding stuffs — the latter being the theme of a 

 valuable book just published by Dr. Armsby of the Connecticut 

 Agricultural Station at New Haven. 



As to soil, the physical conditions are quite as important as the 

 chemical, and, for this reason, the chemical analysis of soils taken 

 by itself fails of being a sure guide to the proper treatment of 

 soils. Take Feat as an illustration : at first, the fact that it con- 

 sists largely of carbon was taken as proof of its value as a fertil- 

 izer. It was applied fresh from the pit, with disastrous results, 

 and was of course abandoned as worthless. The reaction was 

 as unreasonable as the first position ; for a close study of the 

 physical properties of this substance shows a vast capacity for 

 storing water, and when it is freed from deleterious acids it is 

 very useful on leachy soils as a reservoir for water. A proof of 

 this may be seen on a sharp slope in the Free Institute grounds, 

 where I have succeeded in producitig a good durable turf on a 

 bank of hard pan and gravel by laying down first two inches of 

 dry peat, then two inches of compost, harrowing in the grass 

 seed and rolling. It is specially noteworthy that there has been 

 no wash from the foot of the slope. The grass close up to the 

 limit of the fertilized slope seems not to receive the least 

 encouragement from it. 



Again, in the matter of nitrogen compounds Dr. Armsby has 

 shown that the soil does absorb free nitrogen from the air and 

 prepare it for plant food ; i. e. the soil acts first physically I)y 

 absorbing the nitrogen into its pores, and then chemically by 

 putting this absorbed nitrogen in shape for the nutriment of the 

 plant. This explains the importance of keeping all soils light 

 and porous by frequent stirring. 



