70 
Docks being 170 feet. The width at the water level varies from 
130 feet to 230 feet. The depth is 26 feet and the total rise is 
60 feet 6in. The following plant is now in use on the whole 
canal :—86 steam navvies (maximum per day 2,000 cubic yards, 
average 700 cubic yards), 3 French, 83 German, 175 locomotives, 
140 steam engines, 150 steam cranes, 6,500 waggons.—Value 
£1,000,000. 
The various locks, deviation railways, bridges, &c., were 
described, and Mr. Dunkerley’s account of the Barton Swing 
Aqueduct is given as an example of the exhaustive treatment of 
his subject :— 
This aqueduct is to carry the Bridgwater Canal over the Ship 
Canal. At this point the Ship Canal and the old course of the 
Irwell are practically one. As everyone knows, the Bridgwater 
Canal from Worsley to Manchester was the first of a series of 
canals constructed by Brindley. Its history marked an era in 
canal construction, and a glance back into bygone times will 
lead us on to the present high development of this branch of the 
engineering profession. In 1737, the Duke of Bridgwater 
obtained an Act to make a navigable connection between his 
collieries at Worsley and the ‘‘ large village’ of Manchester, but 
for some reason or other which history does not relate, the 
scheme was allowed to collapse. Twenty years rolled by, the 
old duke died and another reigned in his stead; this young man 
was romantic, but, fortunately, in connection with romance, a 
large share of practicability must have entered into his composi- 
tion. Disappointments in early life made him misanthropic, but 
by no means unpractical ; he retired to his estates on the borders 
of Chat Moss, and there in seclusion devoted himself to studying 
the commercial aspect of water carriage as compared with land 
transit. Into his councils he took Brindley, an unknown genius 
at that time, who began life as a wheelwright’s apprentice. In 
1759, Parliament granted him powers to cut a canal from 
Worsley Mill to Salford, also to Hollin Ferry on the Mersey. 
The duke’s idea regarding the crossing of the Irwell, was to 
carry the canal down to the river by a flight of locks, and up 
again on the other side by similar means. Brindley, who was 
quite an unlettered man, with no previous knowledge of canal 
construction, proposed to carry the canal right across the Irwell 
on a viaduct 600 feet long and 36 feet wide, maintaining the 
required level throughout. The duke agreed to his proposal, 
and Brindley carried out the work successfully ; it was spoken of 
by people of the time as a canal in the air higher than the tree 
tops, with horses walking along the battlements to draw the 
laden barges across. Bridgwater spent nearly all his fortune in 
this canal, and at last came to the end of his tether; but after 
long waiting, he in his latter days became rich and Manchester 
