ADDRESS. Ixiii 



applied in the construction of ships of every class. Other considerations, 

 however, affect the question of vessels of war; and although numerous 

 experiments were made, yet none of the targets were on a scale sufficient 

 to resist more than a six-pounder shot. It was reserved for our scientific 

 neighbours, the French, to introduce thick iron plates as a defensive armour 

 for ships. The success which has attended the adoption of this new system 

 of defence affords the prospect of invulnerable ships of war, and hence the 

 desire of the Government to remodel the navy on an entirely new principle 

 of construction, in order that we may retain its superiority as the great 

 bulwarks of the nation. A committee has been appointed by the War Office 

 and the Admiralty for the purpose of carrying out a scientific investigation 

 of the subject, so as to determine, first, the ;best description of material to 

 resist projectiles; secondly, the best method of fastening and applying that 

 material to the sides of ships and land fortifications ; and, lastly, the thick- 

 ness necessary to resist the different descriptions of ordnance. 



It is asserted, probably with trutii, that whatever thickness of plates are 

 adopted for casing ships, guns will be constructed capable of destroying 

 them. But their destruction will even then be a work of time ; and I believe, 

 from what I have seen in recent experiments, that with proper armour it 

 will require, not only the most powerful ordnance, but also a great concen- 

 tration of fire, before fracture will ensue. If this be the case, a well-con- 

 structed iron ship, covered with sound [)lates of the proper thickness, firmly 

 attached to its sides, will, for a considerable time, resist the heaviest guns 

 which can be brought to bear against it, and be practically shot-proof. But 

 our present means are inadequate for the production of large masses of 

 iron, and we may trust that, with new tools and machinery, and the skill, 

 energy, and perseverance of our manufacturers, every difficulty will be 

 overcome, and armour-plates produced which will resist the heaviest existing 

 ordnance. 



The rifling of heavy ordnance, the introduction of wrought iron, and the 

 new principle of construction with strained hoops, have given to all countries 

 the means of increasing enormously the destructive power of their ordnance. 

 One of the results of this introduction of wrought iron, and correct principles 

 of manufacture, is the reduction of the weight of the new guns to about 

 two-thirds the weight of the older cast-iron ordnance. Hence follows the 

 facility with which guns of much greater power can be worked, whilst the 

 range and precision of fire are at the same time increased. But these 

 improvements cannot be confined to ourselves. Other nations are increasing 

 the power and range of their artillery in a similar degree, and the energies 

 of the nation must therefore be directed to maintain the superiority of our 

 navy in armour as well as in armament. 



We have already seen a new era in the history of the construction of 

 bridges, resulting from the use of iron ; and we have only to examine those 

 of the tubular form over the Conway and Menai Straits to be convinced of 

 the durability, strength, and lightness of tubular constructions applied to the 

 support of railways or common roads, in spans which, ten years ago, were 

 considered beyond the reach of human skill. When it is considered that 

 stone bridges do not exceed 200 feet in span, nor cast-iron bridges 250 feet, 

 we can estimate the progress which has been made in crossing rivers 400 or 

 500 feet in width, without any support at the middle of the stream. Even 

 spans, greatly in excess of this, may be bridged over with safety, provided 

 we do not exceed 1800 to 2000 feet, when the structure would be destroyed 

 by its own weight. 



It is to the exactitude and accuracy of our machine tools that our 



