69 
TAB. CCXXXYV. 
Fibrous Gypsum. 
THIS variety is occasionally found near the others in 
broad veins, if I may be allowed to call them so, looking 
like veins on the side of the cliff when exposed, but very 
broad, and varying in thickness and flatness. It is not fit 
for carving figures, as its structure will readily show; but 
for making plaister, for casting, stucco or manure, it is as 
good as the others, and much attracts the attention of the 
common observer by its regular and finely striated ap- 
pearance. It is remarkable for the perfect straightness of 
its fibres, which are sometimes four or five inches or more 
in length, and always divisible even beyond our limits of 
calculation, being an excellent example of a common fibre. 
Lewenhoeck might have said of this as he said of the mus- 
cular fibre, and he would have been nearer the truth—see page 
40 of the second volume of this work. This variety of Gyp- 
sum has something of the appearance of the Satiny Carbo- 
nate of Lime: it, however, is not, like that, sufficiently 
hard to take a polish, but a fresh fracture is equally bright, 
whereas that has not so bright a natural fracture, and re- 
quires polishing to add to its beauty *, The fibres are so 
* Ihave truly stated where the satin-spar is found: Late authors have 
very erroneously quoted Derbyshire for it, where, indeed, it has been sold. 
