of some Calamines. 
Calamine from Derbyshire. 
a. This calamine consisted of a number of small crystals, 
about the size of tobacco-seeds, of a pale yellow colour, which 
appeared, from the shape of the mass of them, to have been 
deposited on the surface of crystals of carbonate of lime, of 
the form of Fig. 28. Plate IV. of the Cristallograpbie of Rome' 
de L’Isle. 
The smallness of these calamine crystals, and a want of 
sharpness, rendered it impossible to determine their form with 
certainty ; they were evidently, however, rhomboids, whose faces 
were very nearly, if not quite, rectangular, and which were in- 
complete along their six intermediate edges, apparently like 
Fig. 78. Plate IV. of Rome' de L/Isle. 
22.1 grs. of these crystals, at a heat of 57° Fahrenheit, dis- 
placed 5.1 grs. of water, which gives their density = 4.333. 
Heat did not excite any electricity in these crystals. 
b. Before the blowpipe, they grew more yellow and opaque, 
and spread flowers on the coal. They dissolved wholly in borax 
and microcosmic salt, with effervescence. 
c. 22.0 grs. during their solution in vitriolic acid, effervesced, 
and lost 7.8 grs. of carbonic acid = 0.354. This solution was 
colourless, and afforded 26.8 grs. of arid vitriol of zinc, which, 
redissolved in water, shot wholly into clear colourless prisms of 
this salt. 
d. 9.2 grs. of these crystals, ignited in a covered tobacco- 
pipe, lost 3.2 grs. = 0.3478 ; hence, these crystals consist of, 
Carbonic acid - 0.348 
Calx of zinc - - 0.652 
MDCCCIII. 
D 
l.OOO, 
