252 
POPULAR SCIENCE REVIEW. 
be made, and armour of 20 inches proves that armour of 
36 inches could be provided, it appears that it lies in the power 
of any nation, who will pay the required price, to construct an 
invulnerable vessel that might destroy everything at present 
afloat by means of her artillery. The rapid development of 
armour, at all events, favours the use of torpedoes and other 
means of attack below the water line, and the shape that naval 
warfare may at any future time assume seems more uncertain 
than ever.* 
* The blocks employed in printing the plate have been kindly lent by 
the publisher of the a Engineer ” newspaper. 
