PRESIDENT HITCHCOCK'S ADDRESS. 171 



of chemistry, enough manure may be derived to add one third 

 to the present produce of our soil. But I cannot go into details. 



Allow me also to repeat a suggestion made in my report on 

 the Agricultural Geology of Massachusetts, respecting the use 

 of what I call Muck Sa?id, dug from a considerable depth in 

 the earth. It is well known to the chemist, that most of the 

 salts so useful upon land, are dissolved by rains, and carried 

 downwards through the soil, till they meet with a water-bear- 

 ing stratum. There they will accumulate ; and now, let that 

 stratum, — known by springs issuing from it, — be dug up and 

 spread over the surface, and these salts will exert their appro- 

 priate influence upon the crops. This very principle is the 

 chief secret of the good effects of subsoil ploughing ; and I 

 doubt not but it will yet lead to valuable results in the use of 

 substances drawn from a still greater depth. In some instances, 

 they certainly have produced astonishing effects. 



Some very ingenious suggestions have lately been thrown out 

 by Liebig, respecting the formation of an artificial manure, that 

 will be almost sure to produce good crops on every soil. It must 

 contain all the ingredients that actually exist in the crops raised 

 by the farmer. Now these have been ascertained with a good 

 degree of accuracy. In the ashes of wheat, beans, peas, pota- 

 toes, clover, and hay, for instance, we find alkaline carbonates, 

 carbonate of lime, phosphate of lime, phosphate of magnesia, 

 sulphate of potash, or soda, magnesia, chloride of iodine, or 

 potassium, phosphate of iron, and magnesia, and carbonate of 

 potash and soda. Silex we need not take into the account, 

 since it exists in all soils. If now to these inorganic substances 

 we add those that are organic, — vegetable or animal, — we shall 

 have all that is essential to sustain the crops that have been 

 named. Hence Liebig suggests, that if we mix the earthy and 

 alkaline phosphates, sulphate of potash, common salt, and chlo- 

 ride of potassium, the salts of lime, and the salts of ammonia, 

 with decaying vegetable matters, we shall obtain a manure that 

 can hardly fail to do admirable service, far more, certainly, than 

 the manures now in use ; especially if these substances may be 

 brought into such a state, that rains shall not wash them away, 

 as they now do. By the same principles, peculiar manures 



