A Chemical Sign of Life

as the diagnostic sign of life. This is what Mr. Tashiro has demonstrated. "That mechanism," he says, "which enables living matter to respond to the external world . . . may be called the most characteristic thing in life. The chemical accompaniment, or basis, of this mechanism, discovered by the author in nerve fibers, he has hoped to show exists in all forms of living matter, both of plants and animals. It gives a chemical method of distinguishing living from dead tissue, and of measuring the quantity of life." "A hundred years ago," Mr. Tashiro reminds us, "the electrical sign of life