Published online by Cambridge University Press: 06 July 2012
The earlier mineralogists laboured under two great disadvantages. They could not readily, on account of the small number of students of chemistry, call in the aid of that science: and at the time when mineralogy was becoming a distinct branch of science chemistry was in itself crude as well as cumbrous. They were thus forced to rely chiefly upon external properties; and, where crystalline form was absent, they were confined to what may be called physical properties alone.
Their knowledge of the composition of bodies being thus limited and uncertain, the old nomenclature was to a considerable extent founded upon external features alone.
page 343 note * The Tiree mineral is greyish-white nialacolite.—M. F. H
page 344 note * See Chapter V. The Micas (Trans. R.S.E., xxix. (1879) 33).
page 348 note * The blank was in the MS. Professor Geikie informs me that the specific gravity lies between 3·1 and 3·24; Scottish examples being nearer to the latter than to the former value.—P. G. T.
page 350 note * Smithson remarks: “Chemical analysis carries destruction along with it, and bestows knowledge of a substance only at the cost of its existence. One remedy which can be offered for this defect is to reduce the scale of operating, and thus as far as possible reduce the amount of the sacrifice.”
page 351 note * I analysed a specimen from Colonel Imrie's collection, and obtained on 13 grammes:—
page 352 note * Min. Mag., vol. vi. No. 28. But no description given.
page 353 note * This yielded on 1·3 grammes:—
Its specific gravity was 3·016.