proposed to be erected at Montrose . 275 
recommending to the attention of the Commissioners the re- 
opening of the Inch channel of the river, as the most effectual 
method of preserving the foundation of this structure from far- 
ther encroachment ; from which alteration this good effect would 
follow, that the violence of the stream, which has carried away 
the channel, would abate, and the waters in their passage to and 
from the basin, would naturally deposit new soil, in place of 
tearing up any farther the bed of the river. 
The next object to be considered, is the fixing of the chains 
in the ground, and this ought to be done so securely, that the 
chains themselves may sooner be torn to pieces than these fast- 
enings should give way or yield in any sensible degree to the 
strain. The most effectual way of attaining this object appears 
to be, to fix at the place where the chains are to be fastened, 
and which will be about SO feet under the surface of the 
ground, as delineated in the principal drawing ; to fix here a 
broad platform of wood, resting on the top of a series of 
wooden piles, driven deep and firmly into the ground, and 
strengthened and supported by diagonal piles driven to oppose 
the strain. This platform to be a square of SO feet, and so 
strongly bound together, and to the piles, that it cannot move 
but in one mass; and after the chains are made fast to it, it is 
then to be loaded with at least 1000 tons of stone or earth, the 
part along the chains being built and vaulted above if necessa- 
ry, that access may be easily had to the fastenings at any fu- 
ture period. The chains, as they approach the platform, are 
to spread out from their compact square of 15 inches, to cover 
at equal distances the whole platform of 20 feet, where each is 
made sure, and furnished, if necessary, with screws to brace it 
to its proper bearing along with the rest, that each may sustain 
its due share of the distending force. In this manner the draw 
of the chains, on each side of die bridge, will be spread over a 
surface of 400 square feet; even at the utmost stretch, there- 
fore, when the bridge is loaded with 1000 tons, or 500 on each 
side, there will only be a draw on the platform of 1| tons per 
foot ; which the weight of the gravel and the stones above will 
be sufficient to oppose, independent of the effect of the upright 
and diagonal piles, which would resist, with many times this 
force, like so many nails driven into a firm board. 
s 
