179 
iSteam Jingvie, 
Table of the relative pressures per square inch^ tempera- 
tures and expansibility of steam at degrees of heat above 
the boiling point of watei\ beginning with the tempei'a- 
tiire of steam of an elastic force equal to five pounds per 
square inchy and extending to steam able to sustain for- 
ty pounds on the square inch. 
Pounds per 
square Inch. 
■ 5‘ 
[Steam of an 
[elastic 
[force pre- 
■dominating 
over the 
pressure of 
tlie atmos- 
phere upon 
a safety 
valve. 
6 
7 
8 
9 
iO 
15 
20 
25 
f 30 
I 35 
L40. 
requires to 
be main- 
tained by a 
’tempera- ' 
ture equal 
to about 
andatlhese 
respective 
degrees of 
^heat, steam' 
can expand 
itself to 
about 
Expan- 
sibility. 
" 5 
6 
7 
8 
9 
15 
20 
25 
30 
35 
.40 
times its 
volume, 
and coiiti- 
nue equal 
^inelasticity j 
to tlie pres- 
sure of the 
atmo- 
sphere. 
And so in like manner, by small additions of tempera- 
ture, an expansive power may be given to steam to ena- 
ble it to expand to fifty, sixty, seventy, eighty, ninety, 
one hundred, two hundred, three hundred, or more times 
its volume, without any limitation but what is imposed 
by the frangible nature of every material of which boilers 
or other parts of steam engines have been or can be made ; 
and prudence dictates that the expansive force should 
never be carried to the utmost the materials can bear, but 
rather be kept considerably within that limit. 
Having thus fully explained my discovery of the ex- 
pansive po^ver and force of steam, I shall proceed to de- 
scribe my improvements grounded thereon ; and in so 
doing, I shall find it necessary to mention the entire steam 
engine, and its parts, to which, as an invention well 
known, I neither can nor do assert any exclusive claim | 
but at the same time I must here observe, that, from the 
nature of my said disco’STryj and its application, there cm 
