CONCLUSION. one 
any attempt upon our part to alter and improve upon 
her scheme must be fraught with consequences whose 
far-reaching influence it is impossible for us to fore- 
tell, and whose ultimate, if not immediate, effect 
upon ourselves cannot but be disastrous in the 
highest degree. 
We may compare our position in the world, in- 
deed, to that of an ignorant man in charge of a vast 
and complicated machine, whose construction he 
does not understand, whose workings he cannot 
stop, but whose motion will continue harmless and 
unaltered so long as he can bring himself to abstain 
from interference with its details. But if, in an ill- 
advised moment, he turn one single handle, or pull 
one single crank, he may open the way for terrible 
and disastrous consequences, of the very possibility 
of which he was totally unaware. And, moreover, 
the fatal mistake once committed, he may find it for 
ever out of his power to redeem his error, while yet 
deeply deploring its results. 
And thus it is with the far vaster and more com- 
plicated machinery of Nature. The power of inter- 
ference is ours, but not the knowledge how that inter- 
ference may terminate. The handles and cranks are 
ready to our hands, but we know not what may hap- 
pen if we lay our hands upon them. We cazunot tell 
what a false step of ours may do. We cannot foresee 
the mischief which may result from our attempts to 
improve upon that which we do not understand. We 
cannot guess how or when such mischief may end. 
And, in the face of all our ignorance, in the face of 
