T rinity Pier of Suspension, 
Yet there are a variety of essential points which it is neces- 
sary for an architect or operative person to be acquainted withj 
which it could not be expected Mr Stevenson could enlarge upon, 
and which, injustice to other important subjects, could not be 
compressed in a periodical Work. I consider, indeed, the erec- 
tion of the Tweed Bridge, and the Pier of Suspension, to be a 
prelude to many other works of the same kind, all subject to 
different arrangement, according to their extent and magnitude, 
the weight they have to support, and every variety of position 
of which the design is susceptible. I have no doubt that the sub- 
ject will be regarded of sufficient importance to engage the at- 
tention of some of our eminent writers on mechanics. 
Without any further allusion to what has before been said of 
the Union Bridge, I may be permitted to mention the fact, 
which is paramount to all others, — that ever since it has been 
opened, it has given entire satisfaction, and has been in constant 
use without any restriction, in the same manner as any other 
bridge of stone or cast-iron. 
The pontage, which is not higher than the road-tolls, has 
paid in the first year more than the interest of the money which 
Was expended in erecting it, including one thousand pounds 
which the trustees voted to me in June last above the estimate ; 
and there is every reason to believe, that it will, in a few years, 
redeem the capital invested. 
A new application of the same principle, has just been success- 
fully completed by the erection of the Trinity Pier of Suspension 
in the Frith of Forth, near Edinburgh, of which a Perspective 
View, Elevation, and Plan, are given in Plate I. Fig.l. % and 3. 
This work was undertaken at the expence of the proprietors of the 
steam vessels employed in the Frith of Forth, and several gentle- 
men forming the Trinity Pier Company. From the increased in- 
tercourse with this part of the coast, by means of steam boats, it 
became almost indispensable for the proprietors to improve the 
landing, and as no arrangement could be made with the trustees 
of the pier at Newhaven, it was proposed by Lieut. Crichton, 
R.N., a principal manager of the London, Leith, Edinburgh, and 
Glasgow Shipping Company, that instead of spending money in 
litigating the right of landing at Newhaven, they should erect the 
present pier ; and the Company are under lasting obligations to 
