of some Calamines. 17 5. No calamine has yet occurred to me which was a real, uncombined, calx of zinc. If such, as a native produc-t, should ever be met with in any of tb§ 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. Printed by W. Bulmer and Co. Cleveland-row, St. Janacs’a. D