214 REPORT — 1860. 



These trusses are placed to cross each other in a reverse diagonal direction, so as 

 to resist either a tensional or compressive strain ; they are made of 5 X 2 flat iron, are 

 securely riveted above to every second or fourth upper deck-beam, and below, a butt 

 on, and are secured to the upper side of the keelson. They are riveted together at 

 their points of intersection, and where they cross the line of the old beams, a double 

 central back-to-back 7X6 angle-iron clamp is riveted to every truss and beam. If 

 desired, a similar angle-iron clamp may be riveted along at the junction of their 

 upper extremities with deck beams. 



The angle of these stanchions is about 60°, that being found best suited to the 

 convenience of the hatch arrangement. The hatchways and masts can easily be left 

 clear. 



It is submitted, these stanchions form a central range of diagonal trussing at a 

 part of a vessel requiring support, and which hitherto has not had such ; they will be 

 of great service in connecting together two strong frameworks, namely a vessel's 

 bottom, and her upper deck platform. The writer also places the diagonal stanchion 

 in athwartship direction ; this he has found reduces vibration in steamers, besides 

 clearing the screw-shaft. On these principles of construction, the writer's firm have 

 nearly completed at Glasgow a 900-ton iron Indiaman, named ' The R. Mackenzie ;' 

 and he is glad to state that the result of such practice has more than realized the 

 expectation formed from the theory ; and respecting the element of expense, he finds 

 that such a vessel costs £2000 less than a Thames or Mersey-built timber ship of 

 the same size and class. 



Plate Butt Frames. — In an iron vessel plated in the common manner, the writer 

 uses butt-frames. In the place of the usual mode of securing the vertical joints of 

 the external plating on an iron internal strop between the frames, they are secured 

 upon a frame in the following manner. There is bent round the exterior of every 

 alternate angle-iron frame, a long continuous plate of some breadth and thickness, 

 as the ordinary butt-strop ; this plate is punched before being fixed to the frame ; the 

 plate-butts or vertical joints are then arranged to be riveted only on this continuous 

 butt-frame. 



If longer outside plating be desired, every third frame may be constructed as a 

 butt-frame. 



If preferred, the continuous butt-strop may be placed between the frames, in one 

 length, from keel to gunwale. 



By either of these modes of securing the butts of common plates, no short butt- 

 strops are required, and it is evident that a vessel having her butts or vertical joints 

 so secured, is greatly increased in point of strength, and that there is little or no 

 liability to break asunder at those points. 



Ceiling. — For the purpose of increasing the strength of iron vessels, the ceiling 

 from the bilge keelson up to the gunwale is made of angle-iron or flat iron in one 

 length placed diagonally and from 12 in. to 10 ft. apart, tailing from the centre of 

 the vessel to the extremities. The port side of a ship being reverse to the starboard 

 side, these diagonal ceiling bars are riveted to the reverse angle-iron of every frame, 

 and their extremities secured to the gunwale angle-iron and bilge keelson. 



These iron ceiling side trusses, in conjunction with my central range of stanchion 

 trussing, yield great strength without occupying space, and both can be adopted 

 with advantage in timber vessels and in battle-ships. If preferred, these diagonal 

 ceiling bars may be of wood in iron vessels. 



Iron Masts. — The writer plates iron masts and spars diagonally from top to bottom, 

 the plates winding round the entire length and riveted together. He also forms an 

 iron mast of diagonal spiral lattice-work riveted together at their points of inter- 

 section. 



If desired, such a mast may be stayed transversely in its interior throughout. The 

 writer also fixes winches to iron masts, with their spindles through the sides of the 

 mast, the aperture required for such spindles being compensated by an internal 

 doubling plate. 



War Ships. — Between the seams of the external planks of wood battle-ships 

 exposed to shot, the writer inserts iron or steel plates, in thickness from l^ to 2 inches, 

 and in breadth the entire thickness of the planks to which they are secured ; these 

 being in long lengths, are bolted vertically to the planks above and below them, and 



