96 TiMEHRl. 
forming a barrage in any of the creeks of the Colony where 
the water does not exceed 5 feet in depth in dry seasons. 
The mode of fixing them is simplicity itself. The 
caisson is fitted together with ends closely planked up, 
it is then floated to its destination. A few men with 
shovels and rakes prepare a bed in the creek, and on the 
water being admitted, the caisson quietly settles down 
into its bed, and if it is found to be on an even keel it 
remains in position, but if it is not level the water has to 
be pumped out and the bed made fair for the second 
trial, and very seldom has a third to be made. The 
planks are now unbolted and the water finds its way 
through the caisson, sluice, or lock, as the case may be ; 
paals are driven and the four corners are sheet-piled 
preparatory to filling in with earth; the iron work is also 
built upon with timber and planking to the desired 
height to which it is intended to confine the water. Of 
course the spot selected in the creek ought to be where 
hio-h land or sand dunes come close down to the creek 
banks, so as to shorten the wing dams necessary to 
confine the water. 
When it is decided to make a lock suitable to pass sea 
punts and other craft, the ordinary lock gates at each 
end become necessary, with the length sufficient to lock 
the usual local trader ; this requires 60 feet in length by 
14 wide, and would, in position, cost $6,000. An or- 
dinary sluice with winding up gear, 30 feet by 14 feet, 
costs in position $2,200. A barrage for an ordinary 
creek with house on top for watchman, and with an 
arrangement of panels to be dropped into a groove, 
instead of a solid door to regulate the height of water, 
