80 Miscellaneous, 



rock of the chain, the structure of all these mountain regions being 

 synclinal, as we have endeavoured to show in the case of the Alps, 

 {SilUman's Journal {2) xxix. 118,) and as Sir Roderick Murchison 

 has beautifully represented in his late section across the Scottish 

 Highlands. (See his new Geol. Map of Scotland). 



MISCELLANEOUS. 



CHROMIC IRON ORE AND ASBESTUS. 

 We copy from a late number of the Chemical News, the fol- 

 lowing notice of the chromic iron and asbestus from the vicinity 

 of Baltimore, lately imported into England. It is known to many 

 of our readers that the Geological Survey has already shewn the 

 existence in several parts of the Eastern Townships, and in Gaspe, 

 of large deposits of this valuable ore, equal in richness to the 

 samples from the United States : — " The amount of sesqui-oxide of 

 chromium in the present ore, as determined by Dr. Genth, is stated 

 to be equivalent to 63 per cent, of chromic acid — a mode of ex- 

 pressing the value of the ore by the quantity of chromic acid 

 produced on fusion with an alkali, and not that of the green sesqui- 

 oxide actually contained therein. Ore of this superior description 

 may be obtained in casks ready for shipment, at the rate of about 

 one dollar for each one per cent, of chromic acid per ton, and in 

 quantities of about 200 tons annually. It is, however, considered 

 more judicious to work this ore in admixture with other qualities 

 which are produced in greater abundance, — 1500 tons annually, — 

 the average composition of such samples furnishing usually 

 about 50 per cent of chromic acid. The ore last described 

 was accompanied by specimens of asbestus, and of paper con- 

 taining about one-third proportion of the same. This mineral 

 may be procured at the rate of 1^ cents per pound, — a low 

 price considering the high quality of the article offered. The 

 specimen sent is beautifully white, and the fibres are long and 

 delicate. It has been tried in America for paper-making and for 

 the manufacture of steam-packing, in both of which applications 

 it is said to be very serviceable. Its property of resisting heat, 

 and its bad conducting power, would render this material particu- 

 larly valuable in connection with steam machinery. The sheet 

 of paper sent is a portion of an experimental manufacture ; it 

 burns with flame, leaving a white incombustible residue, which, 

 with careful management, retains the form of the original sheet ; 

 the weight of ash amounting precisely to 30 per cent." 



