Oyster and Clam Shell Manures

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J. H. Salisbury, State Chemist, New York, has, in the " Plow, Loom and Anvil," presented an analysis of oyster and clam shells, to which the attention of our farmers, near our coasts, should be specially directed. " The common clam shell (Venus mercena-ra)—100 parts of the dry unburned shell gave of Silica......none. Phosphates of iron, lime, and magnesia l'25O Carbonate of li"i . . . . 69 204 Sulphate of lime .... 0-815 Lime, probably combined with organic matter.....13907 Magnesia.....l-400 Potassa......1-847 Chloride of sodium . . . 6-101 Organic matter .... 6 050 100614 Shell of the common oyster (Ostrea borea-lis) —100 parts of the fresh shell, deprived of water, gave of Phosphate of iron, lime, and mrgnesia 0-842 Carbonate of lime . . . 86203 Sulphates of lime .... 2061 Lime, probably combined with organic matter.....6'036 Magnesia . . . . . 0'338 Potassa .....0 191 Soda and chloride of sodium , . 0-690 Organic......3613 99613 From these analyses it will be seen that the shells of the clam contain a much larger percentage of phosphates, magnesia, potassa, and soda, than those of the oyster, while the latter are much the richest in lime and sulphuric tfcid. Soils, containing already a sufficient quantity of lime for present demands, and where the object is merely to compensate for the gradual waste, shells unburned may answer quite as good a purpose as those which have been burned. When used before burning, owing to their compact texture, they are acted upon but slowly by the ordinary agents to which they are subjected, and hence it requires a much larger quantity of them than of burned shells to exert, in a given time, the same degree of influence upon the soil. Unburned, their effects are not materially different—throwing aside the small quantity of animal matter and soluble salts they contain— trom ordinary limestones broken equally fine and disposed of in a similar manner. A locomotive engine factory has been established at Pittsburg, Pa., with a capital of 8150,000. The shares are $5,000 each.

Scientific American Magazine Vol 8 Issue 36This article was published with the title “Oyster and Clam Shell Manures” in Scientific American Magazine Vol. 8 No. 36 (), p. 283
doi:10.1038/scientificamerican05211853-283d

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