■&)* C A x ■ 
general we’fo'fl of t-hc community; and from this time 
forward we are to cor.fider this.great work as facrificed to 
the hopes of gain, of influence, and to jobbing, both with 
refpeit to the courie of the canal, and to its dimeniions.' 
Nature .had pointed'out Bo,rrowjtounnefs, on the Forth, and 
Xjalmuir-burn-foot, fix miles below- Glafgow, on the 
Clyde, as tire two extremities of this inland navigation ; 
■but fuch was the force of influence, that, inftcad of open¬ 
ing the eaft end of the canal at Borrow (taurine fs, where 
there is water at neap-tides for (hips of two or three hun¬ 
dred tons burthen, and lafe lying, it was begun upon the 
.river Carron, at the diftance of a mile from its junction 
with tire Fortli, and four miles above Borrowitounnefs, 
where v-effels of burthen could not float at neap-tides, be- 
fides the delay and inconveniences in navigating the Forth 
and the mouth of .the Catron from floods and contrary 
winds, alfo a circuitous navigation of at lead two miles. 
The depth of water, and dimeniions of the canal, came 
next under cppfi,deration, and gave rife to much confro- 
verfy between the inhabitants of the eaft country on one 
part, and a conliderable number of the inhabitants of 
’ Glafgow on the other. When we confider that the fpace 
to be cut did not, with all its windings, exceed thirty-two 
miles, and that this (hort navigation would at cnce open 
.a communication between the two feas, and all the coun¬ 
tries lying upon thole feas, common fenfe pointed out tire 
propriety of the greated depth of water that the nature of 
the country would admit. This was the defire of the na¬ 
tion in general; and it would have been the intereft of 
Ireland, and of I.ondon, Briftol, Liverpool, and other 
towns in England, to have fubferibed towards a delign in 
which their commerce, -efpecially in time of war, was ma¬ 
terially interelled. Thefe confiderations, however, were 
difregard'ed by the merchants ; and thole of the Scottifh 
nation, who were friends to a deep canal, fee ng them- 
felves overpowered by their opponents, (ubnifited reluc¬ 
tantly to an imperfect navigation. Mr. Smeaton, an able 
-engineer from York (hire, had eflimated the ex pence of 
four, feven, ten, and fourteen, feet wafer. Certain mer¬ 
chants of Glafgow adopted theTcale of four feei; which, 
though fufiicient for (he trade of that city, would fcarcely 
have anfwered any valuable purpole to the nation ; n gene¬ 
ral ; and it was luggeded, no doubt invidiotifly, tliar thofe 
persons never meant that the canal fhould join the Clyde. 
While a bill for cutting the proposed ditch of fottr feet 
water was before parliament, and on the point of being 
palfed, the. end-country gentlemen and traders took the 
alarm, objected to the frivolity .and partial utility of the 
plan, and, fortunately for the public, obtained a bill, ex¬ 
tending the depth of..water to feven feet. It now became 
rseceflary to open a fubfeription, to the. amount of 150,000!. 
which was foon filled : about 130,0001. was actually paid ; 
.and 50,0001. v, as afterwards, added by government. 
Mr. Smeaton began this arduous ta(k in 1768, and over¬ 
came almoft in i irmonntable difficulties in the execution of 
it. The dimeniions of this canal, though greatly con- 
trailed from the original delign, are much fu.perior to any 
work of the fame nature in South Britain. The Englifh 
canals are generally from three to five feet deep, and from 
twenty to forty feet wide, and the lock-gates from ten to 
twelve feet; but they anTwer the purpofe of inland car¬ 
riage from one town to another, for which alone they were 
defigned. The depth of ihe'canal, between the Forth 
and Clyde, is feven feet; its breadth at the furface, fixty 
feet: the locks are fevemy-nve feet long, and their gates 
twenty feet wide. It is railed, from the Carron, by twen¬ 
ty locks in a trail of ten miles, to the amazing height ef 
155 feet above the medium full fed-mark. At the twen¬ 
tieth lock begins the canal of partition, cn the fummit be¬ 
tween. the call and well' feas; which canal of partition con¬ 
tinues eighteen miles on a level, terminal ing at Hamilton- 
hill, a mile north : wC ft of the,Clyde at Glafgow. In 
fome places the canal L carried through molly ground, 
and in others through'folld rock. In the fourth mile of 
the canal there are ten locks, and a fine aejueduci bridge, 
I A L. 
which crblles the great road leading frorp Edinburgh ta> 
Glafgow. The expetiee of this mile amounted to iSgoool. 
At Kirkintulloch tlie. canal is carried over the water of 
Logie on an aqueduct-bridge, the arch of which is ninety 
feet broad, and was built in three different operations of 
thirty feet each, having only one centre of thirty feet 
broad, which was fhifted on l'mall rollers from one ftrerch 
to another. Though this was a new thing, and never at¬ 
tempted before with an arch of this fize, yet the joinings 
are as fairly equal as any other part of the arch. The 
whole is thought to be a capital piece of mafonry. There 
are in rite whole eighteen draw-bridges, and fifteen aque¬ 
duct bridges, of conliderable fize, befide-s fmall ones and 
tunnels. Upon the whole, this canal, even in its.contrail- 
ed (late, exceeds, the mod (anguine hopes of the public 
with refpeCf to its general utility. The diflance between 
the entrance into the Clyde and the Forth is by the Pent- 
land-frith, 600 utiles; by the canal, fcarcely one hundred. 
But this difproportion of diltance, in a fea-voyage, is tri¬ 
fling, when compared with the delays, t lie fhipwrecks, the 
pofirive and cafual expences, attending a paflTage by the 
Hebrides and the Pentland-frith, or even by the Land’S- 
end, particularly in time of war, when the charge of in- 
furanee is from fifteen to twenty' per cent, while by means 
of the inland navigation it feldoin exceeds five per cent. 
Dublin Canal to the Shannon. 
In Ireland a very capital canal has been projected, from 
the city of Dublin to the river Shannon. The cottrfe of 
this canal is carried over the rivers Little Mouell and the 
Great Mouell, and then aero fs the Lilly, by Dowingo and 
the I fie of Allen into the Bog of Allen, and into the ri¬ 
ver Maiden at Tulliinoie, which goes into the Brufria ri¬ 
ver, and falls into the Shannon near Moys-town. A canal 
is cut out of the grand canal in the middle of the Bog of 
Allen into the river Boyne at Edenderry, and another near 
Clonbalk-rk into the river Barrow to Monefleraven, and 
into another branch of the fame river at Portarlington ; 
another cut is al o made to Naaftown, and a f >urth to 
johnltovvn. The « hole length of the cut from Dublin to 
the Shannon is fixty-one miles and a half. 
Another very vulu ible navigation in Ireland, is the ca¬ 
nal from the town of Newry to the fea. The fame canal 
is extended farther than the town, but (lops (hurt of the 
creat object for which it was begun and made, viz. the 
Drurnglafs and Dungannon collieries. There is alfo a 
(hort cut near the town of Limerick,, the benefit of which 
is very fenfibly felt. This country feems to afford ample 
room for further improvement by inland navigation ; and, 
when the bleilhigs of peace (lull return upon 11s, they will 
very probably be fet on toot in this improving-kingdom. 
THE OR V of NAVIGA BLE CANALS. 
The particular operations necefTaiy for making artificial 
navigations, depend upon a number of circum dances. The 
fituation of the ground ; its viemity or connection with ri- 
yers; the eafe or difficulty with which a proper quantity 
of water-can be obtained : thefe and many other circum- 
(lances neceHanly produce great variety in the druihire of 
canals, and augment or dimiirfih the labour and expence 
of executing them. When the ground is naturally level, 
and unconnected with rivers, the execution is eafy, and 
the navigation is not liable to be difturbed by floods': but, 
when the ground rites and'falls, and cannot be reduced 
to a level, artificial methods of railing and lowering vel- 
fels mud be employed, and mult vary according to cir- 
cuin (lances. 
Among the ancients, temporary fltrices were employed 
for railing boats over falls or (hoals in r vers by a very Am¬ 
ple, operation. Two pods, or pillars of mafon-work, with 
grooves, were fixed, one on each bank of the river, at 
fome diflance below the (hoal. The boat having puffed 
thefe pods, planks were let down aero(s fche river, by pul- 
lies, into the grooves, by which the water was r.fifed to a 
proper height for allowing the boat to pufs up the river 
over 
