The Croonian lecture [1798]. Experiments and observations upon the structure of nerves ... / [Sir Everard Home].

  • Home, Everard, Sir, 1756-1832.
Date:
1799
Catalogue details

Licence: Public Domain Mark

Credit: The Croonian lecture [1798]. Experiments and observations upon the structure of nerves ... / [Sir Everard Home]. Source: Wellcome Collection.

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    of an inch, so that the object was magnified about 23 times; and, that the results of the experiments might be as free from optical deceptions as the present state of our knowledge in this branch of science will admit, no appearance is described which Mr. Ramsden was not satisfied of having distinctly seen. The experiments performed with the single microscope were repeated with a double one, made by Mr. Ramsden, which magnified the object about 40 times; but, in the double micro¬ scope, the appearances were indistinct, the reflection from the different glasses having thrown a confused glare upon the moist surface of the nerve. This circumstance led Mr. Rams¬ den to object to the use of compound microscopes, and to con¬ sider them as unfit for viewing objects of this kind. For the following reasons, the optic nerve of the horse was selected, as the most proper for the experiments. It is of a large size, and several inches in length. It is readily procured in a recent state; as there are places in London where horses are allowed to be killed, and regular days in the week are fixed for that purpose. That the examination of the nerve might be made as soon as possible after the animal's death, permission was procured from the man who superintends the killing of horses, to allow Mr. Clift to make the necessary experiments on the spot, the moment the horses were killed. Mr. Clift is the person in¬ trusted with the care of keeping in order the late Mr. Hunter's collection in comparative anatomy, and is well qualified, from his anatomical knowledge, and a familiarity in looking at or¬ ganized parts through magnifying glasses, for an examination of this kind. These experiments were afterwards repeated by Mr. Ramsden and myself. From this mode of conducting