102 On the Expansive Power of Liquids. 



the liquid) be able to overcome any resistance, however great, 

 A slight glance at the relative specific heats of the substance, 

 will show that this waste is equivalent to that obtained from 

 the condensation of about 910 cubic feet of steam at 212°. 



If this quantity of steam is employed in the double stroke 

 steam-engine, it will raise 90 tons 5 feet high. In engines of 

 different powers, this effect is produced in different times. In 

 the 40 horse power engine, for instance, it is produced in ^ of 

 a minute, and in the 10 horse power, in 3^ minutes. Hence, 

 if the alcohol coidd, in one instance, be heated in the space of 

 |- of a minute, and in another in 53^ minutes, the engine we 

 are describing would give us a dynamical effect of an almost 

 illimitable magnitude, at precisely the same expence of time 

 and fuel, as would produce the foregoing definite effect in the 

 two specified steam-engines. But its superiority to these en- 

 gines does not depend upon the supposition, that the expan- 

 sion of the alcohol could be effected during such times as are 

 indicated above. An increase of resistance is evidently of 

 slight consequence with respect to it. And although the pri- 

 mary mover may not perform the effect in the time demand- 

 ed, it may do so by a secondary move, which is connected 

 with it by the means of acceleration. Hence, theoretically 

 speaking, a engine of this sort may be made infinitely superior 

 in every case to the common steam-engine in point of economy, 

 and I might add simplicity. It is evident, however that it 

 would be extremely desirable to expand the alcoho iquickly, 

 and I do not see many difficulties in the way of effecting it. 

 It might be done by sending a quantity of water, at a high 

 temperature, into a spiral pipe in the interior of the vessel 

 containing the alcohol, or into a number of thin rectangular 

 cisterns within it. These pipes or cisterns might be made of 

 thin iron plate, and, by a simple contrivance for always keep- 

 ing them full during cooling, the incompressibility of liquid, 

 upon which the whole engine depends, would save them from 

 being crushed during the expansion of the alcohol. Upon the 

 extent of the surface of these pipes or cisterns, will depend 

 the rapidity of the expansion, and here it may be modified at 

 pleasure. After the piston had reached one extremity of the 

 cylinder, it might admit a stream of cold water into the vessel 



