They tried the machinery of the jack for opening them. They were more
easily opened, but very subject to be deranged, however strongly
made. They returned, therefore, to the original wooden screw, which is
excessively slow and laborious. I calculate that five minutes are lost
at every basin by this screw, which, on the whole number of basins, is
one eighth of the time necessary to navigate the canal: and of course,
if a method of lifting the gate at one stroke could be found, it would
reduce the passage from eight to seven days, and the freight equally.
I suggested to Monsieur Pin and others a quadrantal gate, turning on a
pivot, and lifted by a lever like a pump-handle, aided by a windlass and
cord, if necessary. He will try it, and inform me of the success. The
price of transportation from Cette to Bordeaux, through the canal and
Garonne is ------ the quintal: round by the straits of Gibraltar is
------. Two hundred and forty barks, the largest of twenty-two hundred
quintals (or say, in general, of one hundred tons), suffice to perform
the business of this canal, which is stationary, having neither
increased nor diminished for many years.
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