180 MANURE. 



hen's egg weighs about 1000 grains, of which the shell is 

 about 106 grains. Two per cent, of the shell is albumen, or 

 animal matter ; 1 per cent, phosphate of lime and magnesia, 

 and the balance or 97 per cent, carbonate of lime. At an 

 egg a day, this is equal to li ounce of dry chalk per week. 

 Whence comes this? From soil, from brick-dust, from 

 grain, meal, &;c. But it exists not in soil as carbonate of 

 lime. Animals, like plants, decompose the silicate of lime 

 of soil, and recombine the base with carbonic acid, to form 

 egg-shells. Considering the coi^i.tless thousands of eggs 

 which are produced by the birds of every feather in New 

 England, how big a bit of chalk would their shells produce ! 

 So of fresh water clams ; their shells, common throughout 

 New England, are carbonate of lime. These facts speak 

 volumes. Whenever birds cease to lay eggs, or clams to 

 form shells, then, and not till then, may it be said that New 

 England soil is barren, because it contains no lime. 



216. Flesh, fish, fowl, all animal solids, muscle, gristle, 

 skin, sinews, &c., all afford geine, by putrefaction, and evolve 

 vast volumes of ammonia. Salts are more or less present 

 in all animal substances. There are uniformly found, in the 

 soft or fluid portions, some of the following salts : 



MINERAL SALTS. 



Sulphate and phosphate of lime. 

 Phosphates of soda, magnesia and ammonia. 

 Sulphate and muriate of potash and soda. 

 Carbonates of potash, soda, lime, and magnesia. 



VEGETABLE SALTS. 



Benzoate of potash, soda, lime. 

 Acetate, " " " 



Oxalate, 



