History of the discoveries of the circulation of the blood, of the ganglia and nerves, and of the action of the heart / by Robert Lee.

Date:
1865
Catalogue details

Licence: Public Domain Mark

Credit: History of the discoveries of the circulation of the blood, of the ganglia and nerves, and of the action of the heart / by Robert Lee. 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.

    44/72 (page 40)
    I have seen the dissections described in the following important communi- cation. The ganglia on the ciliac nerves around the iris present the same appearances as the ganglia of the great sympathetic ner^^e in the heart, stomach, and all the other internal and involuntary organs of the body. My dear Father, On sevei-al occasions during the present summer you have shown the greatest kindness in examining some dissections in which I have been engaged of the nerves of the iris. It was no accident which led me to suppose that the movements of the ir's would be found to depend upon a different cause from that which is generally believed. There was every reason to expect tliat the principle which is clearly established by your discovery of ganglia and nerves in the heart and other organs, whose movements are not under the control of the will, would be found to hold good in the case of the ins. It was on the 23d May that you first saw a dissection of the ciliary nerves of the eye of a bullock, and decidedly stated your conviction that the enlargements which were formed upon them, near the circumference of the iris, were true ganglia, and you compared them to those seen upon the surface of the heart. The ganglia, however, in the eye of the bullock are so small and so few in number, that I proceeded to examine the eyes of other animals and birds which possess a greater range of sight and greater sensibility of iris. From dissections of the nerves of the eye of the fowl, the goose, and the grouse, you were satisfied] that an explanation was afforded of all the phe- nomena connected with the movements of the iris. When the ciliary nerves approach the outer circumference of the iris gan- glionic enlargements are formed, from which some filaments pass directly towards the margin of the iris ; others are distributed to the parts imme- diately around. Two or more of the latter of large size unite at a short distance from the first ganglion, to form an enlargement similar to it, and from which nerves are distributed in a somewhat similar manner. Thus a cii'cular chain of ganglia united by nerA'ous filaments is formed in the muscular structure of the iris. By the aid of the microscope ganglionic elements have been discovered in tlie ciliary nerves, but as it is requisite to remove portions of the nerves for examination no idea can be formed of the extent of the complete system. The method which you have employed in your dissections, by which the continuity of the nerves is preserved, is the only one which succeeds in attempting to trace the nerves throughout the iris between its muscular fibres, and in displaying the ganglia to the naked eye. I am, your affectionate son, Robert James Lee. Saville Row, S<'.plcmhcr 8(h, 1865.