Provided, among things, is a method of decreasing intraocular pressure in an animal, including a human, comprising administering an intraocular pressure decreasing amount of a compound of the formula I: . According to the method, the nickel surface is first degreased and is then roughened for approximately ten minutes in a solution containing about one percent of hydrochloric acid, the process being accelerated by adding hydrogen peroxide solution, resulting in the electrolyte turning green. The glass plate 11 has a flange-shaped extension portion 11a, which extends from periphery of the solid rod, and which serves as a holding portion for holding the integrator. The regularly broadcast safety messages themselves are used for time base synchronizing, eliminating the need for separate time stamps or transmissions.