DIMENSIONS OF THE VESSELS. 
27 
for detached service, to be much smaller and of lighter 
draught of water, but to have her stores of the same 
description as the other vessels.” 
They were accordingly built of the following dimen- 
sions : 
Albert 
and Wilberforce. 
Soudan. 
Length on deck . 
. 139 ft. 4 in. 
113ft. 4in. 
Breadth of beam 
. 27 „ 
22 „ 
Depth of hold 
. 11 » 
00 
00 
Tonnage, about . . 
Draught of water when- 
. 457 „ 
1 
249 
ready for the outward 
passage .... 
^ 6 „ 
4 „ 6 „ 
In preparing vessels for such a peculiar service, va- 
rious considerations were necessary. They were built of 
iron in order to have a greater buoyancy, and still further 
to enable them to go into shallow water, they were per- 
fectly flat-bottomed, and without the keel fore and aft, 
as in ordinary vessels. While to supply this deficiency 
at sea, where it would be of serious inconvenience, two 
thick boards, nearly seven feet long and five feet deep, 
were made to slide up and down in water-tight cases in 
the middle of the vessels : that is, in the line of the ordi- 
nary keel, and placed at a suitable distance from forwards 
and aft. These were called “ sliding keels,” and were 
intended to keep the vessels from being blown to lee- 
ward ; which it is evident would be the case with flat- 
bottoms not provided with such a contrivance. 
