+---------------------+---------------------+-------------+ | | Resistance at 0° C. | | | | in International | Approximate | | Metal. | Ohms of a Wire | Temperature | | | 1 Metre long and | Coefficient | | | Weighing | near 20° C. | | | 1 Gramme. | | +---------------------+---------------------+-------------+ |Silver (annealed) | .1523 | 0.00377 | |Silver (hard-drawn) | .1657 | .. | |Copper (annealed) | .1421 | 0.00388 | |Copper (hard-drawn) | .1449 (Matthiessen's Standard) | |Gold (annealed) | .4025 | 0.00365 | |Gold (hard-drawn) | .4094 | .. | |Aluminium (annealed) | .0757 | .. | |Zinc (pressed) | .4013 | .. | |Platinum (annealed) | 1.9337 | .. | |Iron (annealed) | .765 | .. | |Nickel (annealed) | 1.058[1] | .. | |Tin (pressed) | .9618 | 0.00365 | |Lead (pressed) | 2.2268 | 0.00387 | |Antimony (pressed) | 2.3787 | 0.00389 | |Bismuth (pressed) | 12.8554[1] | 0.00354 | |Mercury (liquid) | 12.885[2] | 0.00072 | +---------------------+---------------------+-------------+ The data commonly used for calculating metallic resistivities were obtained by A. Matthiessen, and his results are set out in the Table II. which is taken from Cantor lectures given by Fleeming Jenkin in 1866 at or about the date when the researches were made. The figures given by Jenkin have, however, been reduced to international ohms and C.G.S. units by multiplying by ([pi]/4) × 0.9866 × 10^5 = 77,485. Subsequently numerous determinations of the resistivity of various pure metals were made by Fleming and Dewar, whose results are set out in Table III. TABLE II.--_Electric Volume-Resistivity of Various Metals at 0° C., or Resistance per Centimetre-cube in C.G.S. Units at 0° C._