On the dependence of electrical resistance on temperature

C. William Siemens
1874 Journal of the Society of Telegraph Engineers  
THE experimental researches hitherto published on this subject have been limited to temperatures ranging from the freezing to the boiling point of water, and great uncertainty still prevails regarding the law of increase at temperatures exceeding 100° Cent. The early experiments made by Arndsten* and Dr. Werner Siemens *f * tend to show that copper, silver, and other pure metals offer electrical resistances which increase with the temperature in an arithmetical ratio within the limits of their
more » ... he limits of their experiments, which extended from 0° to 100° Centigrade, whilst subsequent researches by Dr. Matthiessen indicate a slightly divergent ratio between the same limits of temperature. Platinum, which is, in many respects, a suitable metal for extending these enquiries to higher temperatures, has been left Out of consideration in the otherwise exhaustive researches of Matthiessen, and when I first directed my attention to this metal, I observed very extraordinary differences in the electrical conduction of different specimens. I found it impossible to obtain platinum wire of such a degree Platinum of purity that its co-efficient of increment should have a value wre> corresponding with that of silver, and the other pure metals. Some platinum wire, drawn for me by Messrs. Johnson and Matthey . some years since, gave, when measured, a conducting power only 47 times that of mercury. Its increase of resistance was from *
doi:10.1049/jste-1.1874.0024 fatcat:oryknc4akzfddfx6dms2gi6pe4