The specific heats at low temperatures of various metals have recently been determined by Professor Tilden, by U. Behn, and by C. C. Trowbridge. In the following table are given the values obtained by Tilden and by Trowbridge, and some of the numbers obtained by Behn; the numbers given represent the mean specific heats between the temperature of liquid air or of liquid oxygen and the atmospheric temperature. The differences in the method of cooling the metal probably furnish a partial explanation of the discrepancies here shown.