Phosphates of lime

Bone, or osseous tissue, is composed of osteocytes and osteoclasts embedded in a calcified matrix. Hard tissue consists of about 50% water and 50% solids. The solids are composed of cartilaginous material hardened with inorganic salts, such as calcium carbonate and phosphate of lime. 

Kalk. m. lime (equivalent, in old names of salts, to calcium as, phosphorsauerer Kalk, phosphate of lime, calcium phosphate) limestone (Old Chem.) cabc. —. tzender —, caustic lime, quicklime. — gelfischter —, slaked lime. — gebraonter —, quicklime. 

Mr. Hatchett observed that the external skeleton of crustaceans and the egg shells of birds contain more calcium carbonate than calcium phosphate but that in bones the phosphate predominates. It is possible, said he, .. . that some bones may be found composed only of phosphate of lime and that thus shells containing only carbonate of lime and bones containing only phosphate of lime will form the two extremities in the chain.. . . ... 

In Franco, a considerable quantity of glue is made from hones, which are digested in hydrochloric acid, for the purpose of removing the phosphate of lime. 

AH the residues of the oalcinatiou, or of the distillation of animal matters, are fitted for the fabrication of prussiate of potassa, with the exception of animal black, which, in cousequonce of the great quantity of phosphate of lime contained in it, would produce, by calcination with the carbonata of potassa, a corresponding quantity of phosphate of potassa instead of prussian blue.. - ... 

In a recent paper, just received from Baron Liebig, and which contains numerous experimental data, the good effects of chloride of sodium, nitrate of soda, and salts of ammonia are shown to depend, not so much on their intrinsic value, as upon their capacity of dissolving large quantities of phosphate of lime, thus rendering this important salt easily convoyable to the roots of the plants. 

The remarkable fact of the presence, in the watery solution, of phosphate of ]imo, usually considered an insoluble compound, is explained by the observation of Wohler, that bone-dust, moistened will, a little water, in the course of a fow days yields to water a considerable quantity of phosphate of lime, and tins solubility rapidly increases with the putrefaction of the gelatine of bones. Hence, wherever earthy phosphates exist with organic matter, water will invariably dissolve a portion, progressively with the decomposition of the organic matter by fermentation. This fact is of the utmost importance to agriculture. 

Distillation.—The perfectly diy mixture of acid phosphate of lime and charcoal is ground to fine powder in an iron mortar, aud transferred as quickly as possible into the retorts. These, which are of earthenware, are arranged eido by ride in a reverberatory furnace, as shown in Tig. 396. The neck of the retort fits into tho... 

Colored glazes are made with the addition of nearly pure oxides of manganese, copper, iron, chromium, cobalt, et cetera ) opaque glasses, ot enamels, by the addition of oxide of tin, or phosphate of lime for which see Porcelain True and Earthenware, Some of the ordinary lead glazes for soft porcelain are given below —... 

It is most conveniently prepared by adding carbonate of soda to the solution of acid phosphate of lime, obtained by treating bene earth with sulphuric acid. The liquor should be maintained at a boiling temperature and the carbonate of soda must be added as long as effervescence continued, or until the solution has an alkaline reaction. The effervescence is duo to the escape of carbonic acid tbe soda unites with the free phosphoric acid and with a portion of the add of the superphosphate, while at the same time phosphate of lime, or a mixture of this and carbonate of lime, is precipitated. This insoluble matter is removed by filtration, and the liquor is then boiled down and allowed to crystallize. To obtain an additional quantity of the salt from tbe motheT-liquors, it is neocssaiy first to examine if these, manifest an acid or an alkaline reaction. In the first case, more carbonate of soda must he added to restore the alkaline reaction, and the liquor again evaporated and sot aside to crystallize. 

If, on the contrary, too much carbonate of soda has been added originally, the crystak obtained will require to be washed, a fresh portion of the acid phosphate of lime added, the solution evaporated, and again allowed... 

Insoluble salts 0-12 soluble 0-16 consisting of phosphates of lime and magnesia, alumina, sulphate snd oxalate of lime, acetates, malate of 0-28 lime, potassa, and soda, alkaline chlorides, and sulphates,. J... 

Under salts, el cetera, are included malic acid and gum, nitrogenous "subatanoes, fatty matters, aromatic substances, coloring matters, essential oil, chlorophyle, malamide, oxalate and phosphate of lime, phosphata of magnesia, chloride of, ammonium, silicate, nitrate, sulphate, and oxalate of potassa oxalate of soda, chlorides of sodium and potassium, peetates and pectinates of... 

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