An elementary compendium of physiology : for the use of students / by F. Magendie ; translated from the French, with copious notes and illustrations, by E. Milligan.

  • Magendie, François, 1783-1855. Précis élémentaire de physiologie. English
Date:
MDCCCXXXI. [1831]
Catalogue details

Licence: Public Domain Mark

Credit: An elementary compendium of physiology : for the use of students / by F. Magendie ; translated from the French, with copious notes and illustrations, by E. Milligan. 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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    surface, as in every point of its substance ; it possesses every where the same refractive power. However, it is necessary to remark, that the curve of the anterior surface of the lens is very far from being- similar to that of the posterior aspect. This last be- longs to a sphere, of which the diameter is much less than that of the sphere to which the curve of the anterior surface belongs.® Until now it has been understood that the crystalline lens was com- posed mostly of albumen ; but according to a new analysis of M, Berzelius, it does not contain any : it is formed almost entirely of water, and of a peculiar matter that has a great analogy, in its che- mical properties, to the colouring matter of the blood. D. Behind the lens is the vitreous humour, so called, because of its resemblance to melted glass *. Membrane of Each of the parts which we have noticed is enveloped by a humour. very thin membrane, which is transparent like the part that it covers: thus, before the cornea is the conjunctiva; behind it is the membrane of the aqueous humour,'^ which lines all the anterior chamber of the eye ; that is, the anterior surface of the iris, and the posterior surface of the cornea. Crystalline The lens is suiTounded by the crystalline capsule, which ad- capsuie. }]ei-gs by its circumference to the membrane that covers the vi- treous humour. This, in passing from the circumference of the lens, upon the anterior and posterior surfaces of this part, leaves Cronni^™' between an interval, which has been called the canal goudronne? Hitherto it has not been supposed that this canal communicated with the chamber of the eye ; but M. Jacobson asserts that it pre- sents a great number of little openings, by which the aqueous humour can pass out or enter. We have endeavoured to find these openings, but without success. Hyaloid Xhe vitreous humour is also surrounded by a membrane called membrane. ^ hyaloid. This membrane does not alone contain this humour, it is sent down amongst it, and separating, forms it into cells. The details of anatomy, with regai-d to the disposition of these cells, have not hitherto added any thing to what is known of the use of the vitreous humour. The eye is not only composed of parts that are refractive, but * According to M. Berzelius, the vitreous humour contains, of water 98-40; albumen, 0-16 ; muriates and lactates, J-42 ; soda, with an animal matter soluble in water alone, 0-02; total, 100-0.