Excerpt from Ophthalmic Review, Vol. 14: A Monthly Record of Ophthalmic Science Gruber proceeds then to discuss (1) The circulation of diffusible or crystalloid substances, and as a preliminary gives a resume of the results of previous observers. Lehmann found that chromic acid made its way from the concave to the convex surface of the dead cornea. Laqueur made inter-lamellar injections of ferrocyanide of potassium, and obtained Prussian blue reaction both superficially and from the aqueous humour. Injected into the a.c. It gave a characteristic reaction with paper soaked in perchloride of iron at each spot of cornea from which he had previously removed the epithelium; this always took place more quickly at the periphery than at the centre (five to eight minutes at the periphery, twenty to thirty at the centre); and we know that the cornea is permeable in the opposite direction (atropine, Cohnheim, on theoretical grounds, believes the course of the nutrient current must be from periphery to centre and so back to periphery - the route of the leucocytes. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.