TABLE II. +---------------------+-----------------+-------------------------+ | | Mean absolute | Temperatures indicated | |Temperature by an air| dilatations |by dilatation of mercury,| | Thermometer. | of mercury. | supposed uniform.[25] | +---------------------+-----------------+-------------------------+ | Fahr. Cent. | Fahr. Cent. | Fahr. Cent. | | 32° 0° | 0 0 | 32° 0° | | 212 100 | ¹/₉₉₉₀ ¹/₅₅₅₀ | 212 100 | | 392 200 | ¹/₉₉₄₅ ¹/₅₅₂₅ | 400.3 204.61 | | 572 300 | ¹/₉₅₄₀ ¹/₅₃₀₀ | 597.5 314.15 | +---------------------+-----------------+-------------------------+ [Footnote 25: That is, the temperature that would be denoted by mercury inclosed in a vessel having no expansion by heat; or else in one that expanded in the same rate as mercury.] By a series of observations on the apparent dilatation of mercury in glass vessels, compared with the results in the above tables, they deduce the absolute dilatation of glass for each degree of the thermometer, and the temperature that would be indicated by supposing the uniform expansion of a glass rod adopted as the measure of temperature as under: TABLE III. +---------------+--------------+-------------------+--------------+ | |Mean apparent | Absolute |Temperature by| |Temperature by |dilatation of | dilatation of |a Thermometer | |an air Thermom.| mercury | glass in |made of glass.| | | in glass. | volume. | | +---------------+--------------+-------------------+--------------+ | Fahr. Cent. | Fahr. Cent.| Fahr. Cent. | Fahr. Cent. | | 212° 100° |¹/₁₁₆₆₄ ¹/₆₄₃₀| ¹/₆₉₆₆₀ ¹/₃₈₇₀₀ | 212 100 | | 392 200 |¹/₁₁₄₃₀ ¹/₆₃₇₈| ¹/₆₅₃₄₀ ¹/₃₆₃₀₀ | 415.8 213.2 | | 572 300 |¹/₁₁₃₇₂ ¹/₆₃₁₈| ¹/₅₉₂₂₀ ¹/₃₂₀₀₀ | 667.2 352.9 | +---------------+--------------+-------------------+--------------+ The absolute dilatations of iron, copper, and platina were investigated with great address, from 0° to 100° and from 0° to 300° centigrade; and were found as per Table below, for each degree of the centigrade thermometer. TABLE IV. +--------+---------------+--------+---------------+ |Temp. by|Mean dilatation|Temp. by|Mean dilatation| | the air| of iron, |iron rod| of copper | | Therm. | in volume. | Therm. | in volume. | +--------+---------------+--------+---------------| | Cent. | | | | | 100° | ¹/₂₈₂₀₀ | 100° | ¹/₁₉₄₀₀ | | 300 | ¹/₂₂₇₀₀ | 372.6 | ¹/₁₇₇₀₀ | +--------+---------------+--------+---------------+