From accounts printed by the House of Commons in 1812, it appears there had been expended by the Grand Canal company, kr the navigation, only 966,364/. 13a. 9d. In 1806, the directors-gcneral gave this company 54.634/. 18s. 7d. to complete the navigation of that part of the Shannon river between Lough Derg and Lough Rec, to have 6 feet water at all seasons. These works have been completed, but without track-way, at an ex pense of 30,222/. 19s. 3d. beyond the sum advanced to the company. The tolls are more than Id. per ton, per mile, in this part of the Shannon.
The Cermlin and Inny rivers, in the county of Long ford, falling into the Shannon, are sluggish, and have few obstructions ; they have hitherto not been used as navigations.
The Laggan navigation extends from the tideway at Belfast, partly in the river passing Lisburne, Hills• borough and AIoira, into Lough Neal ; total length, 16 Irish miles ; its origin and progress have already bccn narrated.
The river Lee, in the county of Cork, is navigable for masted vessels of 200 tons, to the old bridges of Cork, and for barges about a mile farther, to the head of the island,_ to the NMI Weirs. The only attempt to extend the navigation was the formation of one lock to pass this weir, and a second for another weir, about a mile higher. The project was abandoned, and the lochs arc now filled up.
The Lane and Main, in the county of Kerry, unite and fall into the head of Dingle bay ; they admit sloops to Killeglin and Castleman) ; and it has been proposed to render the Lane navigable into the lake of Killarney.
The Liffey rises in the Wicklow mountains, and fall ing into the sea at Dublin, forms the harbour of that city. It is navigable for three miles, to the upper end of the city, and is provided on each side with excellent quay walls. With a view to regulate and deepen its channel across the extensive strand of Dublin bay, a pier has been built for three miles in length from the shore ; having, in near the middle of its length, a small fort, called the Pigeon House, ‘sith a dock for the Holyhead packets, and an elegant lighthouse at the extremity ; the channel is regularly dredged by lighters. These works have, for upwards of a century, been carried on under the di rection of the Ballast Board ; but notwithstanding the immense sums which have been expended, the harbour of Dublin is still found to be very imperfect, and projects have been formed for making. artificial harbours, either
within or without the bay, to which vessels may safely resort at all times.
The harbour of 'Tonal, originally proposed as the packet station, has been enlarged, with the view of also accommodating trading vessels, and is now nearly completed, at an expense of about 300,000/. granted by parliament ; hut this great work, not appearing to be well calculated for the trade of Dublin, another harbour has been begun within the bay at Dunleary, on the south side, the expense of which will probably exceed that of Houth, and it is supposed a ship canal may, at some future time, be made from it to the city, about 5 miles.
Lough Larne, a lake in the county of Fermanagh, is about 30 miles in length. The river Earne rises in Lough Gounah, on the borders of Longford, and, passing through the county of Cavan, becomes navigable below Belturbct, where it enters Lough Earne. Leaving it again at Enniskillen, the navigation is obstructed by weirs, but below the town it again gradually expands to the breadth of 10 miles. Near Belleek, the navigation ter niinates at the bottom of a fall, or salmon leap ; thence the river passes rapidly for five miles to Balty Shannon, where it falls into Donnegal bay. It has beeo several times proposed to complete the navigation from Beltur bet to Bally Shannon, and for that purpose a 4.,onipany was incorporated in 1790; but, after expending several thousand pounds, the pi ojeca was abandoned.
The lake and river of this name are navigable from Galway westward, for nearly 30 miles, for boats carrying aboul 14 tons. The chief trade is turf, lime, and wain, nto Galway.
The Maig is a branch of the Shannon, in the county of Limerick ; it is navigable for the Shannon boats to near Adare.
Moy, in the county of Mayo, is navigable from Killala bay to Ballina.
The Newry navigation, the first executed in Ireland, extends, 1st. From the tideway at Fathom, 24 miles, to Newry, and admits vessels drawing 9 or 10 feet of water, having a sea lock at each end, 120 feet by 22, and 17 feet deep.
2. From Newry to the navigable river Bann, 12 miles, is a canal for barges of 40 to 60 tons ; it has 30 feet watcr the surface, anc15 feet deep. There are 13 locks, 60 feet by 15. The summit is here 65 feet above the sea, and 22 above Lough Neagh.