Satisfactory reviews of the present knowledge of the pathogenesis of cataract are to be found in the monographs of Jess1 and Siegrist.2 Salit3 has recently restudied, with present-day technic, the chemical composition of the normal lens.
THE CHEMICAL CONSTITUTION OF THE LENS
The percentage of the various constituents of the lens varies with age. With increasing years, there is an increase of total protein, lipoid and electrolytes, accompanied by a loss of water and a marked change in the relative amounts of water-soluble and water-insoluble proteins. From the ages of 2 to 16, the protein content of the lenses of cattle rises from 32 to 37 per cent, while the water content falls from 67 to 62 per cent. In new-born calves, the ratio of water-soluble to waterinsoluble protein is 80 per cent to 20 per cent; but at 16, the ratio is 41 per cent
GIFFORD SR, LEBENSOHN JE, PUNTENNY IS. THE BIOCHEMISTRY OF THE LENSI. THE PERMEABILITY OF THE CAPSULE OF THE LENS. Arch Ophthalmol. 1932;8(3):414–440. doi:10.1001/archopht.1932.00820160108009