458 PHILOSOPHICAL TRANSACTION*. [ANNO 17QQ. 



cisely the same salt as before. Notwithstanding all this, when I reflected, that 

 borax is generated only in certain climates of the east, and that its acid is found 

 only in particular substances and situations, as has been already mentioned, I could 

 not but suppose the latter to be the produce of a new formation. This being pre- 

 mised, I considered maturely in what manner the decomposition of this new and 

 extraordinary compound might be attempted. Admitting the composition to be 

 formed by the coalition of a number of different substances, it seemed not impro- 

 bable that an acid, penetrating into and dissolving the whole mass, would rather 

 associate with some than with others of its various component parts, and thus 

 produce a separation or change of the latter. Besides, as the sedative salt, strong 

 as its operation is, in a high degree of heat, on almost all neutral salts, has but a 

 faint taste of acid, it might be supposed, that its acid is contained within some 

 unknown species of earth, intimately combined ; or within some sort of inflam- 

 mable matter ; or, according to a phrase used in the new system, there might be a 

 deficiency of acid matter ; that therefore some more powerful acid would probably 

 separate and dissolve the earthy particles, destroy or change the inflammable matter, 

 or impart the acid it might be supposed to want. 



My choice, among the different acids, was fixed on that particular one, which, 

 though not always quick in its operation, never fails to penetrate deep into all 

 soluble substances, is nearly related to all inflammable bodies, and possesses an 

 abundance of acid matter : I mean the oxygenated muriatic acid, prepared with 

 manganese. In the application of this menstruum, I resolved to follow the prac- 

 tice established by the constant experience of both ancient and modern chemists; 

 which has taught us, that difficult decompositions of parts closely united, are more 

 easily effected by a gentle, long continued, digestive heat, and repeated distillation 

 of the same menstruum, than by a heat which is more violent, and operates more 

 quickly. I first made some preliminary experiments, in order to judge what pro- 

 bability there might be of success. 



Exper. 1. I poured 1-^oz. of the above-mentioned acid on 2 dr. of sedative salt, 

 in a retort, to which I adapted a proper receiver, and then placed the mixture in a 

 gentle digestive heat, of from 140° to 200° of Fahrenheit. The fluid was distilled 

 over very slowly, and the salt was dry on the 3d day. The salt in the retort 

 seemed unchanged; nor had the marine acid lost any thing of its usual smell. — 

 Exper. 2. I poured the distilled fluid out of the receiver on the same salt, and 

 exposed them to the same degree of heat as before. The salt again became dry 

 on the 3d day, but there was yet no appearance of any change. — Exper. 3. I re- 

 peated the same process a 3d time. I now perceived during the distillatory diges- 

 tion, several bright yellow spots on the salt, as it ascended the sides of the retort, 

 resembling well-formed am moniacal flowers of iron; more of which I discovered 

 after the entire exhalation of the fluid. — Exper. 4. The above change induced me 

 to repeat the distillation ; and I then perceived, not only as many, but a much 



