believed to involve all the excellent points of mines of whatever
nationality, while another extraordinary invention was the non-ricochet
projectile. The ordinary pointed projectile striking the water almost
horizontally is deflected and ricochets. A special type of shell which
did not glance off the surface of the ocean was developed early in 1917
and supplied to all vessels sailing in the war zone.

The first year of the war saw also the development of the seaplane, with
the adaption to this vehicle of the air a nonrecoil gun, which permits
the use of comparatively large calibers, and of the Lewis gun. This year
saw also the completion of the latest type of naval 16-inch gun,
throwing a projectile weighing 2,100 pounds. Our newest battleships will
mount them. In this connection it is interesting to note that broadside
weights have tripled in the short space of twenty years; that the total
weight of steel thrown by a single broadside of the _Pennsylvania_
to-day is 17,508 pounds, while the total weight thrown from the
broadside of the _Oregon_ of Spanish-American War fame was 5,600 pounds.

The navy also went in vigorously for aviation and has done exceedingly
well. After the expansion of private plants had been provided for, the
navy decided to operate a factory of its own, and a great building 400
by 400 feet was erected in Philadelphia in 110 days at a cost of
$700,000. Contracts involving approximately $1,600,000 have been made
which will more than treble the capacity of this plant.

In addition to work of this sort and services including scores of
specialized activities, such as medical development, ordnance and
munitions manufacture, building of yards, docks, and all sorts of
accessory facilities, the navy before the war had been a month under way
had given contracts for the construction of several hundred