Six years later he described the centigrade thermometer in a paper read before the Swedish Academy of Sciences (see Thermometry).
Joule inferred from them that the mechanical equivalent of heat is probably about 772 foot-pounds, or, employing the centigrade scale, about 1390 foot-pounds.
Temperature on the Centigrade Scale.
The following table contains the most probable values for a few of these points which have been determined with the greatest care or frequency: Table of Boiling-Points at Atmospheric Pressure on Centigrade Scale Alphabetical Index of Symbols Empirical constants in formulae; section 14.
The relative abundance of nitrates and nitrites at the bottom of deep oceans as compared with the surface can be explained in the same way, for at the bottom the temperature is about zero Centigrade and the activities of the denitrifying bacteria are practically suspended.
In the measurement of temperature the Fahrenheit scale is still followed for imperial standards, and the Centigrade scale for metric standards.
Processes of annealing, or very gradual cooling, are intended to relieve these strains, but such processes are only completely effective when the cooling, particularly through those ranges of temperature where the glass is just losing the last traces of plasticity, is extremely gradual, a rate measured in hours per degree Centigrade being required.
Adopting the centigrade scale, this gives 1390.846 foot-pounds.