Formation of Flints

IN your report of the discussion that followed the reading of my paper on Flint, before the Geologists' Association on June 2nd, Prof. Morris is said to have asserted that the views I suggested were first propounded by Dr. Brown of Edinburgh. I think the Professor must have been slightly misrepresented in this; at all events I must most decidedly decline to be coupled with Dr. Brown, or to allow myself to be associated with his very remarkable statements. These may be found in the Trans. Roy. Soc. Edinb., vol. xv. He asserts that carbon is transmutable into silicon; at p. 229 he says, “Carbon and silicon are isomeric bodies, and that the former element may be converted into a substance presenting all the properties of the latter.” At p. 244, “3.04 grains of silicic acid were extracted from 5 grains of paracyanide of iron;” at p. 245, “5.4 grains of silicic acid were procured from 30 grains of the ferrocyanide of potassium,” and “there were obtained 9,334 grains of silica from 3,240 grains of ferrocyanide, although some of the product was lost in two of the operations.” The view I advocated as explanatory of the formation of flints was the substitution of silicon for carbon, not a transmutation, and I distinctly showed the source from which the silicon was derived. Dr. Brown's statements are so extraordinary that I could scarcely believe them serious. I find, however, in the same volume of the “Transactions” that they were most patiently examined and confuted by Dr. George Wilson and Mr. John Crombie Brown, and they say, “We tried the greater number of Dr. Brown's processes, and rejected them one after another without pursuing their investigation further, on finding they would not yield quantitative proofs of the conversion of carbon into silicon. The limited time, which from various circumstances we could devote to the subject, obliged us to follow this course; and the confident expectation we entertained till a recent period that each new process would supply what the rejected ones had failed to afford, led us to neglect noting many particulars of our early trials which otherwise we should have recorded. . . . In conclusion, we need scarcely say that we have been unable to supply any proof of the transmutability of carbon into silicon.”