568 
Mr. Lubbock on the Heat of Vapours 
The following example will serve to show in what manner the 
table was calculated. 
Ex. — Calculation of the temperature and volume of steam for 
the pressure of 180 lbs. per square inch. 
log 180 = 2*2552725 
log 14*706 = 1*1674946 
logp = 1*0877779 x *0134 = *01457622386 = log 1*03413 
1*17602 
1*03413 
2*0651059 
log *14189 = 9*1519518 
2*9131541 = log 818*7 
448*0 
Temp. Fahr. Air Therm. = 370*7 
4*8 
Temp. Fahr. Merc. Therm. = 375*5 
0*4109002 
log™ = 8*9122221 
2*9131541 
2*2362764 = log 172 (a. * 172 
The following data are taken from M. de Pambour’s work on 
the Steam Engine, p, 238. 
y _ -25 I V = 250 f = *5 (lb. per square inch) S = *14 
Z = 10 ft. a = 12*566 sq. ft. S = *927 cub. ft. 
p" = 4 lbs. per square inch. c = *05 I 
log V = 2*3979400 
log a = 1*0991971 
log *30 = 9*4771213 
log V = 2*397 9400 
log a = 1*0991971 
log 1*05 = 0*0211893 
2*9742584 
log S = 9*9670797 
3*5183264 
log S = 9*9670797 
3*5512467 = log 3558*3 
y = 3558*3 
30071787 = log 1016*6 
p' = 1016*6 
