AS DEEP extraocular infections of the eye often lead to loss of vision or of an eyeball, every new antibacterial agent has promptly been tried in treatment of such infections. Soon after the bacteriostatic action of penicillin and its additional favorable characteristics, such as absence of toxicity and easy solubility, were established, experimental work by von Sallmann1 and Leopold2 on rabbit eyes showed that systemic or iontophoretic application of this drug did not lead to any detectable concentration in the lens or vitreous. Topical application of penicillin gave high concentrations of this drug in the anterior structures of the eye3 and was effective in treatment of infections of the anterior part of the eye due to penicillin-sensitive organisms, but only direct injection of this drug into the lens or vitreous4 was of benefit in experimental infections of the deeper parts of the eye with certain strains