In order, therefore, to encourage the spirit of im provement which had strongly manifested itself in the northern parts of the island, a board of parliamentary commissioners was established, viz.
The Right Honourable the Speaker of the House of Commons, The Right Honourable the Chancellor of the Ex chequer, His :Majesty's Advocate for Scotland, The Right Honourable William Dundass, Sir 'William Pulteney, Bart, Haac Hawkins Browne, Esq.
Nicholas Vansittart, Esq.
Charles Grant, Esq.
William Smith, Esq.
Charles Dundas, Esq.
John Hickman, Esq. Secretary, James Hope, Esq. Commissioner and Law Agent in Scotland, Thomas Telford, Engineer to the Board.
This Board, upon the application of individuals, or bodies of men, pointing out communications in the Highlands of Scotland, of public utility, and undertak ing to defray a moiety of the expense, causes surveys and estimates to be made, and, if found to be truly useful, advances the other moiety from the public funds. In consequence of this, about sixty different roads have been surveyed, and a great proportion have either been already completed, or arc now (1812) in a state of for wardness. Upon these roads there are bridges of dif ferent sizes, to the number of 1486, and several of no Inconsiderable magnitude, viz.
Bonar bridge, of cast iron, 150 feet span, over an arm of the sea.
Dunkeld bridge, of 7 arches, viz. one of 90, two 84, two 74, two 22 feet.
Conon bridge, of 5 arches, viz. one 65, two 55, two 45 feet.
Ballater bridge, of 5 arches, viz. one of 60, two 55, two 34 feet.
Lovat bridge, of 5 arches, viz. one of 60, two 50, two 40 feet.
Wick bridge, of 3 arches, viz. one of 60, two 48 feet.
Alford bridge, of 3 arches, viz. one of 48, two 60 feet.
Potarch bridge, of 3 arches, viz. one of 70, two 45 feet.
Besides these, there are upwards of 60 bridges of one arch each, from 30 to 60 feet span.
In Ireland, the city of Dublin has several fine stone bridges over the river Liffey, the principal of which arc, 1. Queen's bridge, built upon the scite of Arran bridge, which had been erected in 1684, and destroyed in 1763. It was designed by Colonel Vallency, and was finished in 1768. It consists of three arches ; the middle 46 feet span, the others 35 feet each ; the piers arc 7 feet thick, and the breadth between the parapets is 35 feet. 2. Essex bridge, which was originally founded in 1676, by Sir Humphrey Jarvis, in the viceroyalty of Arthur earl of Essex ; it being decayed, was taken down and rebuilt in 1753, from a design and under the direction of Mr George Semple, who pub fished a very full account of the proceedings. It con sists of five arches, one 58 feet span, three of 45, and one of 37 feet ; the thickness of the piers on each side of the centre arch is 6 feet, the breadth between the parapets 48 feet. 3. Sarah's bridge, consisting of an arch of 110 feet span, with a rise of 22 feet ; the breadth between the iron railing 37 feet. This was built by Mr Stevens, an experienced bridge builder from near Edinburgh, in the year 1792. 4. Since that time Carlisle bridge has been rebuilt ; it consists of three arches, the middle 50 feet span, the others 40 feet each ; the thick ness of the piers 10 feet, breadth between the parapets 63 feet.
There is also a very fine stone bridge over the river Lee, at Cork, built within these few years, with a draw bridge for ships at the north end of it.