We now arrive at Messrs. Maginot & Pinette's system, the description of
which will be greatly facilitated by the diagram that accompanies this
article. The inventors have employed a boat 14 meters in length by 1.8
m. in width, and 65 centimeters draught behind and 32 in front. The
section of the midship beam is 70 square decimeters, and that of the
exhaust port is 4. At a speed of 2.2 meters per second the tractive
stress, K, is from 10 to 11 kilogrammes. At a speed of 13.5 kilometers
per hour, or 3.75 meters per second, the engine develops a power of 12
horses. The piston is 19 centimeters in diameter, and has a stroke of 15
centimeters. The shaft, in common, of the pump and engine makes 410
revolutions per minute. It will be seen from the figure that suction
occurs at the lower part of the hull, at A, and that the water is forced
out at B, to impel the vessel forward. C and C' are the tubes for
putting the vessel about, and DD' the tubes for causing her to run
backward. Owing to the tubes, C, C', the rudder has but small dimensions
and is only used for _directing_ the boat. The vessel may be turned
about _in situ_ by opening one of the receiving tubes, according to the
side toward which it is desired to turn.

This boat is as yet only in an experimental state, and the first trials
of her that have recently been made upon the Saône have shown the
necessity of certain modifications that the inventors are now at work
upon.--_La Nature_.

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