s8 Mr . Smithson’s chemical Analysis , &c. 
5. No calamine has yet occurred to me which was a real, 
uncombined, calx of zinc. If such, as a native product, should 
ever be met with in any of the still unexplored parts of the 
earth, or exist amongst the unscrutinized possessions of any 
cabinet, it will easily be known, by producing a quantity of arid 
vitriol of zinc exactly double its own weight ; while the hydrate 
of zinc, should it be found single, or uncombined with the car- 
bonate, will yield, it is evident, 1 .5 its weight of this arid salt. 
