210 LARY BRIDGE. 



saturated with a composition of bees' wax and rosin, 

 was placed between them. In the top of the bell, len- 

 ses, such as are usually employed, were placed and 

 bedded in the above-mentioned composition. Two 

 hoops of wrought iron were then passed horizontally 

 around the inside and outside of the bell, and screw- 

 bolted together, so as completely to protect the wood 

 work from internal or external pressure. Internal and 

 external iron stays, in which were fixed the sling chains, 

 crossed these horizontal hoops, and connected the top 

 of the bell with the sides ; and being screw-bolted to 

 the hoops, distributed the weight of the bell, when 

 slung, over the whole of the iron framing. The bell 

 was 5 feet 9 inches long, 4 feet 6 inches wide, and 5 

 feet high ; and required an additional weight of 3 tons 

 15 cwt. to sink it. The weights for this purpose were 

 of cast-iron, hung round its sides. As the water was 

 deep and the stream rapid, it was deemed expedient to 

 guard effectually against the escape of air ; the bell 

 was therefore, as a further precaution, lined with sheet 

 lead. Air was supplied to the divers in the usual way, 

 and thus the several operations of levelling the pile- 

 heads, paving the spaces between them, &c. were carried 

 on with ease, certainty and dispatch. 



Platforms, composed of wood and stone work, of 

 the form and dimensions of the several spaces inclosed 

 by the sheeting piles, were constructed on the shores, 

 and the joints being well caulked, and rendered water- 

 tight, the first courses of masonry for the piers and abut- 

 ments were built on them, to a height of from 3 feet 

 6 inches to 4 feet. In order to make this a floating- 

 mass, it was surrounded with wood work made perfect- 

 ly water tight, and connected with the platform sus- 

 taining the masonry, by strong bars of iron, previously 

 fitted to cast-iron sockets, bolted thereto, forming a sort 

 of box about sixteen feet in height, and in length and 

 breadth equal to the platform Thus prepared, the 

 joint, formed by the connection of the sides and endi* 

 with the bottom, was caulked ; and the whole becoming 

 buoyant, was floated from the shore, and sunk on the 



