618

Alkalies and Neutral Salts.

part in.

not very generally prescribed by the physician, although thismay be readily disguised by a small quantity of lemon juice, orof cream of tartar, added to the solution. The dose is fromj$ss. to >pj., but in the effloresced state half of these quantitiesis sufficient.

PHOSPHAS SODiE, Edin. Phosphate of Soda.

" Take of bones, burnt to whiteness and reduced to powder,ten pounds, sulphuric acid, six pounds; subcarbonate of soda, asufficient quantity. Mix the powdered bones with the sulphuricacid in an earthen vessel; then add the water, and again mix :keep the vessel in a vapour-bath for three days: after which, dilutethe matter with nine pounds more of boiling water, and strainthrough a strong linen cloth, pouring boiling water graduallyover it until the whole of the phosphoric acid be washed out.Set the strained liquor apart that the impurities may subside,from which pour it off, and evaporate it to nine pounds. Tothis liquor, separated from its impurities, and heated in anearthen vessel, add a warm solution of subcarbonate of soda,until the effervescence cease: then strain, and set the liquoraside, that crystals may form. These being removed, add tothe liquor, if necessary, a little subcarbonate of soda, that thephosphoric acid may be accurately saturated; and dispose itby evaporation again, to yield crystals, as long as these shallbe produced. Finally, let the crystals be preserved in a well-closed vessel."

Dublin.

" Take of burnt bones reduced to powder, Jive pounds ;sulphuric acid three pounds and a half. Mix the powder withthe sulphuric acid in an earthen vessel; add, gradually, fivepints of water, and agitate the mixture. Digest for threedays, adding from time to time more water, lest the materialsshould become dry, and continue the agitation; then pourover them five pints of boiling water, and strain through a linenrag, pouring on, at intervals, boiling water, until all the acidbe washed out. Set the liquor apart that the impurities maysubside, from which decant it, and evaporate it to one half;then add three pounds ten ounces of carbonate of soda (dis-solved in a sufficient quantity of warm water); filter, andobtain crystals by repeated evaporation and cooling. Thecrystals are to be preserved in well-closed vessels.

" If the salt be not sufficiently pure, repeat the solution andcrystallization."

Syti. Phosphate de Soude (F.), Phosphorsaures Natruro (G.\ Fosfato diSoda (I.).

When bones are burnt to whiteness, the residue is chieflyphosphate of lime, 100 parts of which consist of 4i parts of