ALKALI volatile vitriolatum (vitriolic ammoniac) is ſcarcely found any where but in places where the phlogiſticated fumes of vitriolic acid ariſe from burning ſulphur, and in putrid places are abſorbed by the volatile alkaly.[[24]] Thus at Fahlune the acid vapour from the roaſted minerals produces this ſalt in the neceſſary houſes. It is ſometimes alſo formed in the craters of volcanoes.
ALKALI volatile nitratum (nitrous ammoniac) is generally found along with common nitre.
ALKALI volatile ſalitum (ſal ammoniac or common ammoniac.) I have examined ſome from Veſuvius, and ſome from the Solfaterra near Naples.
The ſalts hitherto enumerated are perfect neutrals, thoſe which follow are imperfect (§§ 53, 56.)
ALKALI FOSSIL, only in part ſaturated with a peculiar acid is called tinkal; after depuration, borax. It is dug out of the earth in the kingdom of Thibet[[25]]. Borax takes nearly an equal weight of acid before the alkaline properties entirely diſappear[[26]].
I believe no one has yet found the acid of borax united either to the vegetable or volatile alkalies.