1879.] The Physical Properties of Liquid Acetylene. 



213 



and the diminution of volume read off at intervals of about 10 atmo- 

 spheres up to about 180 atmospheres. 



Curves were then plotted, showing the volume at different pres- 

 sures for the same temperature, and from these the coefficient of com- 

 pression at any temperature and pressure was easily deduced. 



The following tables are constructed from the curves. 



1. — Mean coefficients of compression of liquid acetylene at different 

 temperatures. Range of pressure from 36'62 to 182*68 atmospheres. 



Temp, of acetylene. Coeff. Temp, of acetylene. Coeff. 



35° C. = -00085 16° C. = -00050 



28-6 = -00068 4-4 = -00038 



22-5 .= -00058 = -00025 



2. — Coefficients of compression at the same pressure but varying 

 temperatures. 



Temp, of acetylene. Atm. 70. Aim. 95. Atm. 120. Atm. 160. 



*49°C -00343 -00169 -00078 



*41 -00138 -00099 '00076 



35 -00171 -00113 -00078 -00065 



28-6 -00122 -00083 -00072 -00050 



22-5 -00079 -00065 -00057 '00047 



16-0 -00066 -00050 -00049 -00035 



4-4 -00047 '00042 -00034 -00032 



-00041 -00036 -00025 -00029 



3. — Coefficients of compression at varying pressures and temperatures 

 corresponding to the same volume. 



Vol. = 97 c.mm. Vol. = 92 c.mm. 



Temp, of acetylene. Pressure. Coeff. Pressure. Coeff. 



*49° C 170-8 atm. -00080 



*41 137 „ '00085 



35 103-2 „ -00093 .... 175-8 atm. -00065 



28-6 ' 70 „ -00120 .... 137"8 „ -00063 



22-5 ' 99-2 „ -00065 



16'0 59'5 „ -00066 



Vol. = 101 c.mm. Vol. = 89 c.mm. 



*49 126-3 atm. '00128 



*41 98-3 „ -00132 



35 72-7 „ -00167 



22-5 158 atm. -00054 



16-0 115-6 „ -00056 



4-4 .... 49-7 „ -00058 



* These two experiments were, of course, made above the critical point. 

 VOL. XXIX. O 



