expansion should cease at that point at which gains and losses just
balance each other.


TO CALCULATE THE LOSSES.

The requisite data are furnished by the experiments conducted some years
since by President D.M. Greene, of Troy College, for the Bureau of Steam
Engineering, U.S. Navy.

According to these experiments, the heat which is lost per hour by
radiation through a metallic plate of ordinary thickness, exposed to dry
air upon one side and to the source of heat upon the other, for one
degree difference in temperature, is as follows:

Condition. Heat units.

Naked...................................... 2.9330672
Covered with hair felt, 0.25 inch thick.... 1.0540710
" " 0.50 " .... 0.5728647
" " 0.75 " .... 0.4124625
" " 1.00 " .... 0.3070554
" " 1.25 " .... 0.2746387
" " 1.50 " .... 0.2507097

If now t' = temperature of steam at the ordinate,
t = temperature of the surrounding atmosphere,
dS = surface of the cylinder included between each ordinate,
k = that figure from the table satisfying the conditions,
then the power loss (dR) per minute will be: