cial submarine boat is advocated by Mr. Lake.
This is to be used for the location and collection of shellfish on a
large scale. Of this vessel its inventor says:

The design of this submarine oyster-dredging vessel is such that
the vessel goes down to the bottom direct, and the water is
forced out of the centre raking compartment so that the oysters
may be seen by the operator in the control compartment. With only
a few inches of water over them, headway is then given to the
submarine and the oysters are automatically raked up, washed, and
delivered through pipes into the cargo-carrying chambers.
Centrifugal pumps are constantly delivering water from the cargo
compartments, which induces a flow of water through the pipes
leading from the "rake pans" with sufficient velocity to carry up
the oysters and deposit them into the cargo holds. In this manner
the bottom may be seen, and by "tracking" back and forth over the
bottom the ground may be "cleaned up" at one operation.

This boat has a capacity of gathering oysters from good ground at
the rate of five thousand bushels per hour. The use of the
submarine will make the collection of oysters more nearly like
the method of reaping a field of grain, where one "swathe"
systematically joins on to another, and the whole field is
"cleaned up" at one operation.

Man's greediness for profit has already driven the salmon from the
rivers of New England where once they swarmed. Mechanical devices
for taking them by the hundreds of thousands threaten a like result
in the now teeming rivers of Washington and British Columbia. Mr.
Lake's invention has the demerit of giving conscienceless profiteers
the opportunity to obliterate the oyster from our national waters.

[Illustration: Permission of _Scientific American_.

_Sectional View of a British Submarine._]

It does not appear, however, that, except as an engine of war the
submarine offers much prospect of future development or future
usefulness. And as we of the United States entered this war, which
now engages our energies and our thoughts, for the purpose of making
it the last war the world shall ever know, speculation on the future
of the submarine seems rather barren. That does not mean however
that there will be a complete stoppage of submarine construction or
submarine development. War is not going to be ended by complete
intern