VOL. XXXVIII.J I'HILOSOPHICAL TRANSACTIONS. 5g9 



The phlogistic part is so slightly connected with the other principles, that 

 the least motion, friction, or warmth, sets it on fire. 



The fixed part seems to consist chiefly in the acid salt of the urine; which 

 is at first so intimately concentrated with the phlogistic part, as in deflagration 

 to be hurried up or sublimed along with it; yet being by this operation freed 

 from it, it becomes fixed, and can by no degree of heat be again sublimed. 



Phosphorus may be called a urinous sapo, or soup, as it consists of the saline 

 and oleaginous parts of the urine: but phosphorus is not to be got in so great 

 plenty out of urine alone, as when the faeces alvinae are elixirated along with it, 

 and then brought to a magma fit for distillation : nor is there so great a quan- 

 tity of phosphorus in the urine of other animals, as of men ; nor is it to be 

 got from any natural productions, or any parts of animals or vegetables in their 

 crude state, before they have undergone concoction in the stomach of an animal. 

 How far therefore the liquor gastricus, the bile, and succus pancreaticus may 

 contribute to the formation of it, is a disquisition he does not here enter on, 

 but leaves it to the inquiry of philosophers. 



As to the parts of which phosphorus consists, it may be considered as the 

 soot of a deflagrated oil; and so may every combustible substance be considered 

 as a kind of phosphorus, as consisting of inflammable materials. 



Phosphorus is more immediately compounded of a salt tending to the nature 

 of sal ammoniac, of a urinous salt, of an acid, and an oily phlogiston with a 

 subtle earth ; by means of these salts existing in the urine, the fasces alvinse 

 are the better elixirated, and those particles extracted which contribute to 

 form the phosphorus. With these salts are very intimately combined, in 

 the phosphorus, oleaginous or fat particles, which are the proper materials of 

 that subtle phlogiston, the true domuncula ignis, and indeed the main con- 

 stituents of the whole compound.* 



As for the preparation of this wonderful production, it is done by distilling 

 the saponaceus magma in a close vessel, with a reverberatory fire, much stronger 

 than that used for the distillation of aquafortis, or the other mineral acid spirits; 

 the rest of the proper encheiresis belongs only to the operator to manage se- 

 cundum artem. When this operation succeeds rightly, there comes forth, 

 1st, A thick, unctuous oil. 2dly, A more subtle oil, resembling the oleum phi- 

 losophorum, which is olive oil distilled from brick-dust. 3dly, The fixed acid 

 inclosed in a very subtle acid. Near the end of the distillation, comes over 

 that depurated oil, which constitutes the inflammable part of the phosphorus, 



* Mr. H. represents phosphorus to be a very mixed compound indeed ; whereas in tlie present 

 day this inflammable body is considered as a simple substance, the basis of the phosphoric acid. 



