362 Mr. Raukine on the Hypothesis of Molecular Vortices, 



the definition of temperature is, that bodies at the same tempe- 

 ratm-e are in a permanent condition as to heat, so far as their 

 mutual action is concerned. 



The ratio of the real specific heat of («) to that of (i) is ob- 

 viously 



haka:h,h (14) 



(7.) Measure of Temperature and Specific Heat. — Tlie func- 

 tion 6 is proportional to the pressure of a perfect gas at a con- 

 stant density. That pressure, therefore, is the most convenient 

 measure of temperature. 



Let T denote absolute temperature, as measured by the press- 

 ure of a perfect gas at constant density, and reckoned from a 

 certain absolute zero, 27i°-6 Centigrade, or 494°-28 Fahrenlieit 

 below the temperature of melting ice. Let k be a constant 

 which depends on the length of a degree on the thermometric 

 scale, and is the same for all substances in nature. 



Then 



'"„ \; (16) 



and the real specific heat of the substance, that is to say, the 

 depth of fall, under the influence of gravity, which is equivalent 

 to a rise of one degree of temperature in the body, is repre- 

 sented by 



"=!-«• d") 



The pressure of a perfect gas is represented in terms of tem- 

 perature by 



^=a^^ • ■ • a^) 



It may also be expressed thus : let Tq denote the absolute 

 tem]jerature of melting ice in degrees of the scale employed, and 

 \q the volume of unity of weight of the substance in the theo- 

 retical state of perfect gas, at the temperature of melting ice and 

 pressure unity ; then 



^=t'7 (i«) 



On comparing this with equation (17), we see that 

 hf^ _Vo. 



_ hjXTQ hfJb _ K 



