A number of researches have been published concerning the effect of the introduction of various substances, solid and liquid, into the vitreous chamber. These may be summariztd as follows:
1. The introduction into the vitreous of foreign bodies (pieces of wire, lead, glass, etc.), or of irritating liquids (croton oil, tincture of iodin, etc); 2. the injection of sterilized blood into the vitreous humor; 3. intra-ocular injections of various antiseptic liquids.
Researches belonging to the first class, from the time of the publication of Pagenstecher's essay on the pathology of the vitreous to Leber's superb work, are chiefly concerned with the behavior of the vitreous towards these foreign substances, and with the complex problems which surround the pathology of inflammation. Researches of the second class, which date from the imperfect experiments of Legros, to the thorough investigation of the subject of blood injections into the vitreous by Pröbsting, have been