TRANSACTIONS OF THE SECTIONS. 213 



The decks may be laid also diagonally in a reverse direction to the beams, and may 

 be edge-bolted throughout and made of hard wood. 



This system of decks, by which the objcctional butts are entirely avoided, i3 

 more particularly adapted for 4 or 5-decked battle-ships, where the strain from the 

 weight of the guns and action of propeller is found to strain and twist them so 

 much. 



Iron Waterways are formed in the following manner. Every iron beam is made with 

 a vertical projection on its upper edge at both ends ; this projection is about 7 inches 

 deep and 20 to 40 inches broad, according to the tonnage of the vessel. On the 

 upper edge of these projections are riveted double-angle iron. On the front or bosom 

 of these projections is riveted, in long lengths along the beams, heavy angle-iron, 

 say 6 + 5. Over this are then placed the plates which form the waterway ; these are 

 rounded over on their inside edge, which is riveted to the heavy angle-iron inside ; 

 the top of the plate is double riveted down to the double angle-iron on each beam 

 end : the outer edge is riveted to the angle-iron along the sheer strake, where it is 

 securely iron-caulked. 



Round any angle-iron frames necessary to project through the waterway is fitted 

 exactly a doubling piece, which is securely caulked round the frame. 



The usual iron stringer and wood water-ways are thus superseded, and this iron 

 water-way, it is submitted, forms a serviceable and complete box gunwale. 



The beam-end projections form also stronger and improved knee fastenings, par- 

 ticularly to the upper part of the beam, where hitherto in iron vessels such a knee 

 has not yet been adopted, although considered essential in timber vessels. 



In fact, for the convenience of stowage and passengers' berths, the knee or the 

 under side of all iron beams on this principle might be dispensed with. Of course, 

 this waterway can be adopted with either diagonal beams or common beams. 



Plating diagonally with two tbicknesses of plate, each in the reverse diagonal 

 direction to the other, or with one thickness in combination with frames arranged in 

 the reverse diagonal direction. 



In the former case, both thicknesses of plating will be riveted together, and the 

 butts arranged to make shifts with each other ; by this mode of construction the 

 present vertical frames become unnecessary, and even the keel not essential. In 

 place of these are substituted, in long lengths, internal longitudinal stringers, 

 clamps and keelsons, about 5 feet asunder; these would have the advantage over the 

 present internal longitudinal fastenings, of being fitted and secured directly to the 

 skin of the fabric through which they may be fastened every 3 inches ; by this 

 system it is not requisite that the plate butts be more securely riveted than the rest 

 of the external skin, as it will be evident that such a vessel could not break asunder 

 at the butts or vertical joints like a postage-stamp, as was described in the case of 

 many late wrecks of iron ships constructed on the present mode. 



Timber vessels of 2000 tons have been planked on this principle with complet 

 success. 



Keelsons made in the following manner have greater strength as a backbone, and the 

 necessary rigidity to receive the thrust of diagonal central hold stanchions or trusses. 

 Every floor, or alternate floor, is made to project up in the middle in the form of a 

 square. Round these projections are fixed angle-iron, to which the upper and side 

 plates of the keelson are secured in the form of a box. Bilge and sister keelsons may 

 be also formed on the same principle. 



The keelson required by Lloyds for their highest classed iron vessel, has only four 

 rivets to secure it to the top of each floor ; consequently, when by accident the strength 

 of the bottom is tested, these rivets of course break, leaving the strength of the floors 

 and keelson as a backbone untested, while with the above improved keelson, the 

 floors are so well fastened to the keelson, that they must break before the keelson 

 will yield. 



Diagonal Central Hold Stanchions or Trusses. — In place of the common vertical 

 hold and 'tween-deck pillars or stanchions in two lengths at present in use in wood 

 and iron vessels, most of which are made portable, and intended merely for the sup- 

 port of the deck, the inventor forms, from stem to stern, a range of diagonal trussing 

 in bars of one length, the joint object of which is to strengthen he fabric and sup- 

 port the deck. 



