The Lens and its Capsule

Speaking anatomically, the lenticular opacities, i.e., cataracts, are different according to whether the nucleus or the cortex is involved. There is a difference between the nucleus and the cortical substance….


THE crystalline lens, or crystalline body, is a doubly convex transparent solid body, with a rounded circumference; it is inclosed in a capsule, is situated behind the pupil, and in front of the vitreous body.

In Bowman’s words, the capsule of the lens, a transparent glass-like membrane closely surrounding the contained body, is hard and brittle, especially in front, but very elastic and permeable to fluid. The anterior surface is in contact with the iris towards the pupil, and recedes from it slightly at the circumference; the posterior rests closely on the vitreous body. Around the circumference is a space, called the Canal of Petit. The fore part of the capsule is several times thicker than the back, as far out as 1/16 of an inch from the circumference, where the suspensory ligament joins it; but beyond that spot it becomes thinner, and it is thinnest behind. In its nature the capsule of the lens resembles the glassy membrane at the back of the cornea, for it is structureless, and remains transparent under the action of acids, alcohol, and boiling water, and when ruptured, the edges roll up with the outer surface innermost.

By “structureless” is meant that our strongest magnifying powers are unable to show any further differentiation. It is very tough and exceedingly elastic.

The histology of the lens is admirably given in Stricker’s Manual of Human and Comparative Histology, vol. iii., which is translated by Dr. Power for the New Sydenham Society (London, 1873).

It is the work of Professor Babuchin, who was ably assisted by Sernoff. But it is much too elaborate for the present purpose.

Max Tetzer’s Compendium der Augenheilkunde, Gruenfeld’s third edition, Vienna, 1878,-by the way the best Manual of Ophthalmology extant,-is a mine from which we shall dig a little. Poor Tetzer was the most genial clinical instructor of his day (alas! so short), and made almost every student feel that he would go in for the eye. He puts the anatomy and histology of the lens thus tersely: The lens, with its posterior surface, fits into the plate-like groove of the vitreous. The connection of the posterior part of the capsule in this groove, is however, very loose, so that the capsule can be readily taken out. Of the greatest importance is the layer of the intracapsular cells, that are very pretty epithelial cells, like mosaic. This epithelium of the capsule, lying on its inner surface, is to be regarded as the matrix of the fibres of the lens. Particularly those cells towards the periphery give rise to the formation of the fibres of the lens.

The lens substance has a peculiar shape; its anterior surface is flatter, the posterior surface more convex. The proportion in the convexity is as ten to six. In the lens we distinguish the nucleus and the cortical substance. The cortical substance is rather softer, somewhat succulent; the nucleus, on the other hand, is a compact mass. The cortical substance can be divided into leaves (laminae), but the nucleus cannot be divided into leaves. Towards the equator the cortical substance is most considerable. This depends upon the development of the lens, because the peripheral layers are the youngest, while those layers that surround the nucleus are the oldest. The color of the lens in young individuals is as clear as water; the older the person the more it becomes metamorphosed, turning yellow, yellow- brown, even rusty-brown.

Structure of the Lens Substance.

The fibres of the lens are its most important constituent; they are six-sided prisms, so that on section of a lenticular fibre we get a hexagon. One fibre fits accurately to the other. The ends of the fibres are jagged like a saw, whereby the connection is more intimate. The fibres consist of a membrane, a contained fluid, in which globulin or crystalline was discovered, and of a nucleus, which, however, exists only in the young; in the older it has already disappeared.

James Compton Burnett
James Compton Burnett was born on July 10, 1840 and died April 2, 1901. Dr. Burnett attended medical school in Vienna, Austria in 1865. Alfred Hawkes converted him to homeopathy in 1872 (in Glasgow). In 1876 he took his MD degree.
Burnett was one of the first to speak about vaccination triggering illness. This was discussed in his book, Vaccinosis, published in 1884. He introduced the remedy Bacillinum. He authored twenty books, including the much loved "Fifty Reason for Being a Homeopath." He was the editor of The Homoeopathic World.