Evening capital. (Annapolis, Md.) 1884-1910, 1890-10-07
-tMary A. Mason.

Ericsson and the Evolution of Ships.
The first device of man for carrying
himself and goods upon the water was
probably the raft After it came the
trunk of tree, followed out to increase
buoyancy. Next, perhaps, in the series
of devices for conveyance by water was
the canoe made of bark or skin stretched
on frame work. Then boats were made
of pieces of wood stitched together with
thongs or rope. Later came boats of
plank bolted together with inserted ribs
and decks, or half decks. Last in the
series that ends in the ship was the ves-
sci, the frame work of which was first
set up and the planking of the hull put
on afterward. The idea of decked
ship once reached, the next step of prog
ress was to increase the size, capacity,
and powers of propulsion of the floating
house. The earliest representations of
ships are those found in Egypt, which
carry us back some 5000 years before
Christ The ships of that day were all
ready of considerable size, carrying a
large and varied cargo. They had masts
and sails, and the war ships had ram
with which to run down an opponent.
Steering was effected by paddles, four or
five in number. The Phoenicians, the
English of that period, greatly improved
the structure of ships. The ruins of an
Assyrian palace represent Phenician
vessel of two banks of oars-a bireme-
of the period 900 B. G. Shields hung
along the side constituted its armor.
invention of the bireme, and also of the
trireme, or vessel of three banks of oars.
The latter was the Greek ship of war
of the best period. 1t was the long ship
the ship of war par excellence. With
it were fought those notable actions so
well described by Thucydides. Later,
huge vessels with four, five, and even 16
banks of oars were built, the last mem
toned, however, being merely the ex-
pensive toys of wealthy kings. The
yes els of the period of the war between
the Athenians and Peloponnesians were
propelled by both oars and sails, the war
ships relying principally on their oars
The Romans used the Corinthian quin-
quiremes until the fight at Actium
showed that the light Thurman galleys
were better These galleys were biremes
and fully decked. The medieval galley
differed from the ancient in the use of
longer oars and in peculiarities Of con-
struction that enabled more than one
man to be employed upon each oar. The
stroke was thus slower than in the tri-
RENE, but more powerful. The intro
duction of muskets and cannon in lieu
of spears and swords led to the building
of larger ships on the modern models for
purposes of war, until the noble three
decker was reached. The Introduction
of steam as means of propulsion
brought in further changes, and the use
of steel instead of wood for the hull has
wholly altered the old forms and proper
tions of ships both for commerce and
war. With the use of iron for the con-
struction of ships, naturally came the
idea Of converting the ships into float
ing fortress by thickening her sides. A
departure from the merchanteer type
was the immediate result. But as the
walls of ships were thickened the pene-
trating power of cannon was increased,
and this led to the use of special con-
structions to give the ship the quality of
an unsinkable platform, presenting a
small target to the enemy. The progress
made in the last 90 years in the con-
struetion, propulsion, armoring, and
Of ships was largely due to
Ericsson's inventive genius If he did
not invent, he introduced the screw as a
means of propelling ships-a step of
which, by discarding sails, has
the sailors calling. He
first. in the construction of the Prince
ton, placed the @vitals" of war ships
engines, magazines, etc. = below the
water line, out of reach of hostile shot
The expedient of using forced draught
to quicken the fires of ships was his,
rs was also the telescope smokestack,
and the device for using centrifugal
blowers for purposes of ventilation. On
the Princeton he introduced the novelty
of 12 inch wrought iron gun, with Q
band shrunk on at the breech; a device
for taking up the recon of heavy guns;
an automatic gun lock, and en- instru-
ment for determining distances. Among
his other inventions connected with
were the self registering
deep sea lead, until recently in universal
use, and improvements IN tubular steam
boilers. Ericsson's system of movable
torpedoes, operated and steered from
the shore by means Of compressed air
was an important contribution to naval
warfare. His inventions in this line
must affect profoundly the conditions
under whichnavaI operations win hence
forth be conducted. The Destroyer,
small vessel with q gun In the bow
under the water line, for firing sub
marine torpedOes. was amone his last