vi editor's preface. 



considerable quantity of phosphates for their formation, — 

 for they are shown by analysis to contain a large propor- 

 tion, — it follows as a consequence, that the richer in these 

 the food of cattle is, the better they must thrive, the quicker 

 they will be ready for market, and the more they must im- 

 prove in their general condition. There is, however, one 

 consideration often overlooked. A surface of land has only 

 room for a certain quantity of vegetation, and all attempts 

 to make it bear more must fail. If a manure be given 

 which will make the Indian com plant grow to double the 

 usual size, and bear double the usual quantity of heads, it 

 must have more room to grow, and must not be planted so 

 close as in the usual manner. In manuring with abundance 

 of guano, if only the same distance be allowed from hill to 

 hill, the circulation of the air and the ingress of the rays of 

 the sun are so much impeded, that the plants are drawn 

 up, and smut or mildew supervenes. 



The great principle of the absorption and powerful reten- 

 tion, for the use of vegetation, by clay, of the valuable 

 alkaline salts of potash, soda, and ammonia, which was first 

 publicly promulgated by the editor, in January, 1851, in 

 Boston, the discussions on which by Professor Way have 

 created considerable interest in Engand, may here be inci- 

 dentally alluded to, as it will certainly not escape the sa- 

 gacity of Dr. Stockhardt. 



The practice of manuring with clay is not new to many 

 intelligent farmers; it strengthens, as they term it, light 



