492 . Transactions of the American Institute. 



stance that will add to its efficacy, can afford to invest monej' in 

 commercial manures. Under these circumstances he can each year 

 safely and profitably invest a portion of his capital in the purchase 

 of reliable kinds. IVIineral food cannot be appropriated by plants 

 except in solution. There is no doubt that the most economical 

 method of applying manures, is. to reduce them to i\ liquid. How- 

 ever, this method is not always practicable, and in default we must 

 avail ourselves of the next best plan of receiving equal distribution. 

 In case the ground is very rich, it makes but little difference 

 whether the manure is decomposed, but if the crop has to draw 

 the whole or a large part of its sustenance from the manure as 

 applied, then thoroughly rotted manure is the best. The maxim, 

 *' What is gained in speed is lost by power," is as true in agricul- 

 ture as in physics. Farmers that desire immediate effects no 

 longer rely on unfermented manure, or coarsely ground bones, but 

 use instead manure fully decomposed, and bones ground to the 

 fineness of wheat flour. 



The section of country lying south of the Potomac, including all 

 'the Southern States, has for many years depended mainly on Peru- 

 rian guano. But, strange as it may seem, the farmers in many 

 parts have lost confidence in its reliability. Not that it fails to 

 produce large and quick returns, but because its stimulating effects 

 on the soil are found to cause a sure deterioration year by year. 

 The land, productive from its temporary excitement, aa it were, 

 becomes exhausted of its inherent vitality, and, to produce the 

 same yield, a constantly increasing amount is demanded every 

 season. 



Agriculture and political economy say the same thing on this 

 point. Sooner or later Southern planters and Northern farmers 

 will find it in every way to their profit to depend on ground bone, 

 superphosphate of lime and fish guano. The bone and superphos- 

 phates are well known, but the latter should be in more general 

 use. It is two-thirds as valuable as Peruvian guano, and the price 

 per ton is only one-third as much. It is a valuable fertilizer, and 

 deserves the attention of our farmers. At this point the query 

 may arise, "What constitutes a good fertilizer?" This is fully 

 answered by giving the constituents that are found in the ashes 

 of cultivated plants. Phosphoric and sulphuric acids, potash, 

 lime, soda and a few other mineral substances of minor import- 

 ance. In connection with these, to secure a good fertilizer, a 

 certain percentage of matter should be present that on decompo- 



