No. 129] 387 ' 



Prof. Mapes proposed as the next subject, " The lelatiFe value 

 of mineral manures, and Algae." 



The Club adjom-ned to next Tuesday. 



H. Meigs, Secretary. 



American Institute, ? 

 Farmeri Club, November 18, 1851. 5 



Rev. Joseph Carter in the chair j Henry Meigs, Secretary. 



Professor Mapes. — I proposed the subject for this day — the 

 relative value of mineral man tires. The importance of these in 

 connection with the barn yard manures, cannot be rated too 

 high. Soils become exhausted of some of the minerals as well 

 as the organics. Science readily settles the question as to what 

 mineral (inorganic) substance is absent from the soil, and how 

 much it is necessary to add. Liebig has been unjustly reproach- 

 ed. When he began his investigations, he soon discovered, on 

 examining the constituents of plants, the necessary proportions 

 of the inorganic elements. He found that in the ashes of all 

 plants were the inorganic parts that belong to the earth, and the 

 organic, which properly referred to the atmosphere; that the 

 latter constitute about nine-tenths of the substance of plants. 

 By decay, by distillation, by fermention, &c., the organics find 

 their way to their atmospheric home. He manufactured manure, 

 and sent it to England, without a sufficient regard to the great 

 difference of climate between his country and England ; conse- 

 quently it failed. Had he added to his manure the proper amount 

 of nitrogen, he would have succ-eeded in England. The barn-yard 

 manure, which always contains it, should be added to the miner- 

 al compound. No two farms are exactly alike in their constitu- 

 tion. One wants what another lias sometimes too much of. This 

 variation may be acre by acre. Many have said that a bottom 

 heat must be had for mineral manures. Dr. Johnston has said so. 

 No doubt exists of the necessity of nitrogen, and that is furnished 

 by the mucous and oleaginous parts of barn-yard manure ; these 

 stimulate the growth of })lants. Common sea sand will, with the 

 proper additions, grow plants as well as the richest soils. Liebig 



