gsminmag Mineralogical Magazine Mineralogical Magazine 0026-461X Mineralogical Society 10.1180/minmag.1879.003.14.02 XII.—On the Cause of the Production of Different Secondary Forms of Crystals Sorby H. C. LL.D., F.R.S.; President G.S., etc. 10 1879 3 14 111 113 Copyright © 1879, The Mineralogical Society 1879