he case may be.

In order to avoid the risk of a spent torpedo destroying a friendly
vessel, a valve is arranged in any suitable part of the outer casing, and
is weighted or loaded with a spring in such a manner that when under way
the pressure of the water keeps the valve closed, but when it stops the
valve opens and admits water to sink the torpedo.

In our description we have only given the main features of the invention,
the inventor having mentioned to us, in confidence, several improvements
designed to perfect the details of his invention, among which we may
mention the steering arrangement and arrangements for attacking a vessel
provided with what our contemporary, _Engineering_, not inaptly terms a
"crinoline," _i. e._, a network for keeping off torpedoes. The transverse
dimensions of our engravings have been considerably augmented for the sake
of clearness.--_Mech. World._

* * * * *

DUPUY DE LOME.

M. Dupuy De Lome died on the 1st Feb., 1885, at the age of 68. It may be
questioned whether any constructor has ever rendered greater services to
the navy of any country than those rendered by M. Dupuy to the French Navy
during the thirty years 1840-70. Since the fall of the Empire his
connection with the naval service has been terminated, but his
professional and scientific standing has been fully maintained, and his
energies have found scope in the conduct of the great and growing business
of the _Forges et Chantiers_ Company. In him France has undoubtedly lost
her greatest naval architect.

The son of a naval officer, M. Dupuy was born in October, 1816, near
L'Orient, and entered _L'Ecole Polytechnique_ when nineteen years of age.
In that famous establishment he received the thorough preliminary training
which France has so long and wisely provided for those who are to become
the designers of her war-ships. After finishing his professional
education, he came to England about 1842, and made a thorough study of
iron shipbuilding and steam navigation, in both of which we then held a
long lead of France. His report, subsequently published under the title of
"Memoire sur la Construction des Batiments en Fer"--Paris, 1844--is
probably the best account given to the world of the state of iron
shipbuilding forty years ago: and its perusal not merely enables one to
gauge the progress since made, but to form an estimate of the great
ability and clear style of the writer. We may