OBSERVATIONS ON MURIATIC ACID. |g| 



uncommon and rather painful fecretion of tears. I have not 

 yet examined this gas, as there was invariably an inflammation 

 of the mixture, with explofion and rupture of the veffels, al- 

 moft as foon as it began to be evolved. When pure, the 

 r^peroxigenized muriates do not precipitate any of the me- 

 tallic falts, although I believe they decompofe fome. The 

 order in which the bafes feem to be attracted by the acid, is, 

 potafh, foda, barytes, ftrontia, lime, ammonia, magnefia, alu- 

 mina, filica. The other earths I have not tried, and but few 

 of the metallic oxides. 



Firft Species. Hyperoxigenized Muriate ofPotq/Ii. 



This fait is the beft known of all the faline combinations of " yp e t r a £ t mur ' 

 this acid. It has been erroneoufly considered as limply oxige- i 



nized, for its acid is really hyperoxigenized. It is foluble in 

 about fixteen parts of cold water, but in much lefs of warm ; 

 and is eafily feparated, by cryftallization, from muriate of pot- 

 afh. Alcohol can diflblve a fmall portion of it. It feems ca- Probably capable 

 pable of exifting in more Hates than one ; for, in paffing a eiil* ^fo^ flJteL 

 rent of oxigenized muriatic acid, very flowly, arid in the dark, 

 through a folution of potafh, till faturated, I have obtained 

 flexible and fhining needle-like cryftals. This leads me to 

 fufpecl, either a hyperoxigenized muriate of potafh with excefs , 



of acid, or that acid with a fuperaddition of oxigen. It would 

 be fuperfluous to enter into a minute defcription of a fubftance 

 So well known as hyperoxigenized muriate of potafh ; but, it 

 being the fubftance whence I have chiefly attempted to difen- 

 gage the acid, I fhall enter into a particular detail of the a&ion 

 of the more powerful acids upon this fait. 



If concentrate fulphuric acid be poured upon hyperoxigen- Attempt to de- 

 ized muriate of potafh, a violent decrepitation, fometimes but J: " 1 ? *" 5 j' b y 

 rarely accompanied by a flafh, takes place. A thick heavy ed to the fait. 

 vapour, of a greenifh yellow colour, which rifes with difficulty Peculiar vapour. 

 to the top of the veflel, if it be deep, is difengaged. The 

 fmell is not altogether unlike nitrous gas ; but it is peculiarly 

 fetid, and may be compared to that which is emitted by brick- 

 kilns, mixed with that of nitrous gas. It differs much from 

 oxigenized muriatic acid gas ; the latter being pungent and 

 penetrating, the other heavy and oppreffive ; and it does not 

 produce, at leaf! in fo great a degree, the catarrhal fymptoms 

 caufed by the other. At the bottom of this vapour is a bright 



orange- 



