Tonometric measurements of albino rabbits were determined with and without the use of a gel lens while the intraocular pressure (IOP) was manometrically controlled. The IOP was evaluated over a 50-mm Hg range of pressures. A high degree of correlation between measurements made with and without a gel lens was found. The results suggest that the technique may have clinical applications on patients for whom a corneal anesthesia is contraindicated or on whom repeated tonometry or tonography might cause corneal trauma.