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Electric conducting powers of the metals of the allkalies and alkaline earths
287
Electric Conducting Powers of the .Metals of the ./tlkalies and .3lkaline Earths. Dr. A. Matthiessen has made, under the direction of Prof. Kirchhoff of Heidelberg, a series of experiments on this subject, the method of performing which, is fully described in the London, Edinburgh and Dublin Philosophical .Magazine, for February. Tbe following are the results. The temperatures are in centigrade degrees. The conducting power of silver at 0 ° being = 100. That of Sodium at 21"°7 Magnesium 17" Calcium 16'8 Potassium 20'4 Lithium 20" Strontium 20.
~ = ~ ~ = ~
37"43 ~25'47 22"14 20"85 19'00 6.71
The potassium and sodium used, were commercial ; the others were obtained electrotypically. Experiments were also made, and are reported in the original paper, on the variation of the condncting power by heat. In these results an interesting fact was observable, viz: that at some distance from the point of fusion, as well in the liquid as in the solid state, the decrements in the conducting power with the increase of temperature were almost in proportion, but near the point of fusion the decrease in the conducting power became much more rapid; with sodium this change appears to be very sudden, whereas with potassium it seems gradual. This difference in these metals corresponds with their different behavor in fusion; namely, potassium does not become suddenly liquid like sodium, but first passes through a semi-fluid state.
FRANKLIN INSTITUTE.
Proceedings of the Stated .Monthly .Meeting, .March 19th, 1857. John Agnew, Vice President, in the chair. B. Howard Rand, Recording Secretary, P. T. A letter was read from the Virginia and Tennessee Railroad Co. Donations to the Library were received from the Astronomical Society of London, and Charles Wye Williams, Esq., London ; L. A. H. Latour, Esq., Montreal, Canada ; Hon. James Dixon, U. S. Senate ; Hon. Job R. Tyson, U. S. Congress; Lieut. I. M. Gillis and Prof. A. D. Bathe, Washington City, D.C.; University of Michigan, Ann Arbor, Michigan ; Mercantile Library Association, St. Louis, Missouri ; Young Men's Mercantile Library Association, Cincinnati, Ohio ; The Virginia and Tennessee Railroad Co., Lynchburgh, Va.; The Maryland Institute, Baltimore, Md.; Robert (3. Walker, Esq., Hvrrisburgh, Penna. ; and Messrs. T. Y. Medlin, James D. Rice, Prof. J. F. Frazer, Trustees of the Philadelphia Gas Works, and the Mine Hill and Schuylkill Haven Railroad Co., Phila. The Periodicals received in exchange for the Journal of the Institute, were laid on the table.
Electric Conducting Powers of the .Metals of the ./tlkalies and .3lkaline Earths. Dr. A. Matthiessen has made, under the direction of Prof. Kirchhoff of Heidelberg, a series of experiments on this subject, the method of performing which, is fully described in the London, Edinburgh and Dublin Philosophical .Magazine, for February. Tbe following are the results. The temperatures are in centigrade degrees. The conducting power of silver at 0 ° being = 100. That of Sodium at 21"°7 Magnesium 17" Calcium 16'8 Potassium 20'4 Lithium 20" Strontium 20.
~ = ~ ~ = ~
37"43 ~25'47 22"14 20"85 19'00 6.71
The potassium and sodium used, were commercial ; the others were obtained electrotypically. Experiments were also made, and are reported in the original paper, on the variation of the condncting power by heat. In these results an interesting fact was observable, viz: that at some distance from the point of fusion, as well in the liquid as in the solid state, the decrements in the conducting power with the increase of temperature were almost in proportion, but near the point of fusion the decrease in the conducting power became much more rapid; with sodium this change appears to be very sudden, whereas with potassium it seems gradual. This difference in these metals corresponds with their different behavor in fusion; namely, potassium does not become suddenly liquid like sodium, but first passes through a semi-fluid state.
FRANKLIN INSTITUTE.
Proceedings of the Stated .Monthly .Meeting, .March 19th, 1857. John Agnew, Vice President, in the chair. B. Howard Rand, Recording Secretary, P. T. A letter was read from the Virginia and Tennessee Railroad Co. Donations to the Library were received from the Astronomical Society of London, and Charles Wye Williams, Esq., London ; L. A. H. Latour, Esq., Montreal, Canada ; Hon. James Dixon, U. S. Senate ; Hon. Job R. Tyson, U. S. Congress; Lieut. I. M. Gillis and Prof. A. D. Bathe, Washington City, D.C.; University of Michigan, Ann Arbor, Michigan ; Mercantile Library Association, St. Louis, Missouri ; Young Men's Mercantile Library Association, Cincinnati, Ohio ; The Virginia and Tennessee Railroad Co., Lynchburgh, Va.; The Maryland Institute, Baltimore, Md.; Robert (3. Walker, Esq., Hvrrisburgh, Penna. ; and Messrs. T. Y. Medlin, James D. Rice, Prof. J. F. Frazer, Trustees of the Philadelphia Gas Works, and the Mine Hill and Schuylkill Haven Railroad Co., Phila. The Periodicals received in exchange for the Journal of the Institute, were laid on the table.