1HON SHIPS. 



propelled it into a convenient position for cleaning and 

 loading. Its own gravity caused it to fall into the 

 required place for being again fired. The slides also 

 served as friction-bars to regulate the recoil. 



The gun and the slides carrying it were enclosed in 

 a wrought-iron box, having openings in the front and 

 rear for the passage of the muzzle and the breech. The 

 muzzle front of the box was pivoted to the deck by a 

 strong bolt as a centre of motion, whilst its rear was 

 supported on two small wheels resting on the deck, 

 allowing the gun to change its line of horizontal fire by 

 sweeping from the centre pivot. The gunner's seat 

 moved with the carriage, from which he could elevate 

 or depress the muzzle by a lever. The gun was self- 

 priming and self-cocking ; the powder charge was 

 enclosed in a copper case. Captain Moncrieff's patent 

 gun-carriage of the present day is described in words 

 somewhat like those used by Trevithick forty years 

 before. " The recoil lifted a weight smoothly and 

 without friction ; the gun and the weight were held in 

 the position arrived at by a catch until the gun was 

 loaded and ready to fire again." l 



The iron boat mentioned in his note to Lord Cochrane 

 as being made at Hayle, was u for the purpose of send- 

 ing to London to show the method of constructing ships 

 on this plan, roomy, strong, and cheap," and was thus 

 spoken of in a newspaper of the 26th April, 1829. 

 " The * Scotsman ' alludes to the intended construction of 

 iron steamboats at Glasgow by Mr. Neilson: " For fear 

 of the public being misled on this subject, we beg to 

 state that so far back as last Christmas twelvemonths 

 we saw Trevithick, of Cornwall, superintending the 

 construction of an iron man-of-war launch, with the 



1 Sec ' The Times,' August 12th, 1870. 



