Three memoirs on the developement and structure of the teeth and epithelium, read at the ninth annual meeting of the British Association for the Encouragement of Science, held at Birmingham in August, 1839 / by Alexander Nasmyth.

Date:
1841
Catalogue details

Licence: Public Domain Mark

Credit: Three memoirs on the developement and structure of the teeth and epithelium, read at the ninth annual meeting of the British Association for the Encouragement of Science, held at Birmingham in August, 1839 / by Alexander Nasmyth. Source: Wellcome Collection.

Provider: This material has been provided by the Royal College of Physicians of Edinburgh. The original may be consulted at the Royal College of Physicians of Edinburgh.

    39/86 (page 3)
    stance, and of fibres passing through it.” The writings on the subject by Retzius, Milller, and others, leave us to conclude that the interfibrous substance does not present any traces of peculiar conformation :—but I am disposed to believe that it is not only organized, but so differently and cha- racteristically so in different animals, as to be ca- pable of affording valuable aid to the naturalist in classifying the animal kingdom.* [In illustration of this subject, I beg to refer to the drawings, showing the characteristic varie- ties of this conformation [two of which, marked Fossil Ivory, No. 8 and 10, are engraved in PI. C. 5, at the end of the present papers]. The beau- tiful characteristic varieties of this cellular confor- mation in different classes of animals, show the de- licate nature of the process of transition by which it is produced.] * It has been absurdly attempted to show that, in my papers delivered at Birmingham, I supported the old theory of the for- mation of ivory by “ excretion,” or “ exudation,” from the pulp. Neither of those words, however, occurs at all in my papers; and the corresponding ideas were equally absent from my mind. Moreover, the slightest reflection will convince even a tyro in anatomy, that the above simple announcement of a characteristic and in every case beautiful cellular organiza- tion of the interfibrous substance of ivory, is diametrically op- posed to such a theory. How could this organization be the result of a process of exudation or excretion ? In short, to speak of the excretion or exudation of ossified cells, is a ridiculous absurdity. When, on first entering upon my researches into the structure and formation of ivory, I discovered, by an examination of extremely thin sections of the latter, the cellular arrangement of its inter- B 2