176 FERGUSON'S LECTURES. 



LECT. now most productive mineral districts must long ere this have 

 v - been abandoned, had not the steam engine been employed as an 

 ^ active auxiliary in those stupendous works. In the draining of 

 fens and marsh lands, this machine is in the highest degree va- 

 luable ; and in England, particularly, it might be rendered still 

 more generally useful. In practice it has been ascertained that 

 an engine of six-horse power, will drain more than eight thou- 

 sand acres, raising the water six feet in height; whilst the cost 

 of an engine for this species of work, including the pumps, will 

 not exceed seven hundred pounds. This is more than ten wind- 

 mills could perform, at an annual expenditure of several hundred 

 pounds ; while, in the former case, the outgoings will not ex- 

 ceed one hundred and fifty pounds per annum. To the mariner 

 also, the steam engine offers advantages of a no less important 

 and novel nature than those which have already been described. 

 By its use he is enabled to traverse the waters both against wind 

 and tide, with nearly as much certainty, and, as the machinery 

 is now constructed, with much less danger, than by the most 

 eligible road conveyance- It too frequently, however, happens 

 that the faults of any new invention are unjustly magnified, 

 while its real advantages are seldom duly appreciated ; and this 

 axiom has been fully verified, in the clamour so unjustly raised 

 against the application of the steam engine to nautical purposes. 

 Accidents are now, however, but of rare occurrence ; and it is 

 more than probable, that the great improvements which have 

 been made in the boiler and safety-valve, will effectually secure 

 these parts of the engine from a recurrence of such tremendous 

 explosions as characterised the first introduction of steam navi- 

 gation. And, lastly, the political economist must hail with the 

 most heartfelt gratification, the introduction of so able and effi- 

 cient a substitute for animal labour as the steam engine. For it 

 has been calculated that there are at least ten thousand of these 

 machines at the present time at work in Great Britain, perform- 

 ing a labour more than equal to that of two hundred thousand 

 horses, which, if fed in the ordinary way, would require above 

 one million acres of land for subsistence ; and this is capable 

 of supplying the necessaries of life to more than fifteen hundred 

 thousand human beings. 



