DURING the past few years many investigators1 have studied the physiologic and pathologic effects of the fluorophosphates. Of these, the diisopropyl derivative ("DFP") has received most attention. It has been shown to be a powerful inhibitor of cholinesterase2 and therefore has pronounced parasympathomimetic and nicotinic actions. It is much more potent than physostigmine in these respects. In the eye, "DFP" has been shown to produce prolonged and marked miosis, spasm of the ciliary muscle, false myopia and decrease in intraocular tension.3 The ocular effects of "DFP" far outlast those produced by other known miotic agents. For example, miosis was found to last two days in the rabbit,4 ten days to two months in the cat5 and three to nine days3a and fourteen to twenty-seven days3b in man. The spasm of the ciliary muscle has been found to last three to seven days in