On the mode of formation of shells of animals, of bone, and of several other structures : by a process of molecular coalescence, demonstrable in certain artificially formed products. / by George Rainey.

  • Rainey, G. (George), 1801-1884.
Date:
1858
Catalogue details

Licence: Public Domain Mark

Credit: On the mode of formation of shells of animals, of bone, and of several other structures : by a process of molecular coalescence, demonstrable in certain artificially formed products. / by George Rainey. Source: Wellcome Collection.

Provider: This material has been provided by King’s College London. The original may be consulted at King’s College London.

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    with their now solid contents, these edges become sharply serrated. Lastly, in and towards the centre of the lens, where the coalescence is complete, the dentate lines which indicate the lateral extent of the radiating fibres become obliterated, showing, at this part, a thorough incorporation of the material of which they are composed, and with this the process of molecular coalescence of the lens termi- nates. Mr. Nuuneley, in a paper contained in the ‘Quarterly Journal of Microscopical Science’ for April, 1858, gives a plate of the epithelial cells from the posterior part of the capsule of the lens of a sheep, showing lines of cells, concerning which he observes that “ were it not that similar cells are found in Petit’s canal I should feel inclined to think that they are not merely the means of nutrition to the lens, but that they are lens-fibres in progress of development.” This observation seems to me to show that Mr. Nunneley would have persisted in enter- taining his first impression as to the nature of these cor- puscles, which I have no doubt is the right one, had he not been diverted from this view by some preconceived physio- logical theory concerning the nutrition of the lens. The dentate lines, corresponding doubtless to the radiating lines of feeble attraction in the artificially formed calculi, are the last to become obliterated; and this does not take place until the predominant force is the attraction of tenacity. These lines are distinctly serrated only in the fish, being merely undulating and irregular in mammals. The circumstance of irregularity in these fines, as con- trasted with that of the artificial and some of the natural products, is probably to be accounted for by the difference of mechanical conditions under which in the two cases they are formed. These conditions in the former,—the artificial product—applying at the same time to the entire spherical