 | 1847 - 492 str.
...equal to 114-5 Fahrenheit degrees. For the sake of perspicuity I have generally taken them at 115°. thick. As used in these experiments, it could maintain...constant light. A strip of that metal, one inch long and ^th of an inch wide, connected with a lever by which its expansion might be measured, would yield at... | |
 | 1847 - 490 str.
...and a half in diameter, three high, and one-third SKCOHD SXRIII, Vol. IV, No. 12.— Nov., 1847. 51 thick. As used in these experiments, it could maintain...constant light. A strip of that metal, one inch long and ^th of an inch wide, connected with a lever by which its expansion might be measured, would yield at... | |
 | Charles W. Vincent, James Mason - 1848 - 400 str.
...of the investigation. UNIT LAMP. AT the close of the paper just quoted, Prof. Draper remarks : — " Among writers on optics, it has been a desideratum...supplying that want, and give us what might be termed a ' Unit Lamp.' A surface of platinum of standard dimensions, raised to a standard temperature by a voltaic... | |
 | American Academy of Arts and Sciences - 1885 - 590 str.
...current is really due to Dr. John W. Draper, of New York, who in 1847 enunciated it as follows : " A surface of platinum of standard dimensions raised...constant light. A strip of that metal one inch long and j^th of an inch wide, connected with a lever by which its expansion might be measured, would yield... | |
 | American Academy of Arts and Sciences - 1885 - 602 str.
...electrical current is really due to Dr. John W. Draper, of New York, who in 1847 enunciated it as follows: "A surface of platinum of standard dimensions raised...constant light. A strip of that metal one inch long and ...',, in of an inch wide, connected with a lever by which its expansion might be measured, would yield... | |
 | Sir Norman Lockyer - 1879 - 622 str.
...the colours emitted followed the true prismatic order as the temperature increases. Dr. Draper says: "Among writers on optics it has been a desideratum...supplying that want, and give us what might be termed a 'unit lamp.' A surface of platinum of standard dimensions raised to a standard temperature by a voltaic... | |
 | National Academy of Sciences (U.S.) - 1877 - 764 str.
...preceding experiments furnish an easy means of supplying * * * what might be termed a ' unit lamp.' A surface of platinum of standard dimensions, raised...voltaic current, will always emit a constant light. (27) :!G1 A strip of that metal one inch long and one- twentieth of an inch wide, connected with a... | |
 | John William Draper - 1878 - 502 str.
...thermometer becomes more striking, because we should scarcely have anticipated that it could be so complete. Among writers on Optics it has been a desideratum...supplying that want, and give us what might be termed a " unit lamp." A surface of platinum of standard dimensions, raised to a standard temperature by a voltaic... | |
 | John William Draper - 1878 - 496 str.
...experiments furnish an easy means of supplying that want, and give us what might be termed a " unit lamp." A surface of platinum of standard dimensions, raised...constant light. A strip of that metal, one inch long and -gV °f an iQch wide, connected with a lever by which its expansion might be measured, would yield... | |
 | Illuminating Engineering Society - 1910 - 1022 str.
...d ''Among the writers on Optics it has been a desideratum to obtain a light of standard brilliancy. A surface of platinum of standard dimensions raised...constant light. A strip of that metal one inch long and 1/20 of an inch wide connected with a lever by which its expansion might be measured would yield at... | |
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Among writers on optics, it has been a desideratum to obtain an artificial light of standard brilliancy. The preceding experiments furnish an easy means of supplying that want, and give us what might be termed a "unit-lamp. 
