Los Angeles herald., 1907-11-10
Science and Invention

So far the depth to which diver can
descend would appear to be limited by
his power for withstanding the adverse
influences acting upon him while carrying
on his duties under water, says the New
York chipping Illustrated Apparently
descent of thirty fathoms of water marks
the limit of safety for even the few div
ers who possess the necessary physical
fitness in combination with a disregard
for danger beyond the average. Records
in deep-sea diving have to be accepted
with the proverbial grain of salt. 1t is
said that a diver reached thirty-three
fathoms and half while engaged in sal
wage operations on the west coast of
South America; and, yet again, another
diver working on the same wreck Is re-
ported to have brought up three bars of
copper from depth of forty fathoms at
the expense OF his life. A diver away up
in Puget sound is also credited with the
rescue of some materials from the wreck
of tug at thirty-tnree fathoms. Cap
tain Eads, while experimenting his great
work at the South pass and on the Mis-
sissippi, found that very few men, what
ever their build, are capable of combating
the severe strain which is brought to
bear upon their physical energies for
few minutes at depth of twenty or
thirty fathoms. Many of his divers dared
lOl NCilulC DSAOW lSil ldLlODlS. vi ops
divers employed at greater depths thirty
were seriously injured, and the result was
fatal In ten instances. In 1855 the steam
er Alfonso XII was lost off Point Gando,
Grand Canary, with ten boxes of specie
on board The Marine Insurance COM
pany sent out three divers, Alexander
Lambert, David Tester, and F. j. Davies,
who succeeded in getting up nine out of
the ten boxes with their contents intact.
Lambert was most successful, and suf-
fered from paralysis of his internal or
gans in consequence, but appears to have
recovered under skilled treatment on
shore. In a subsequent expedition, sent
out to recover the missing tenth box,
Tester lost his life, presumably by re-
naming under water too long without
returning to the surface. During the
first expedition Lambert received $4,000
and Tester about 81400; as they were paid
regular wages, per centum on the value
recovered and bonus of ESQ box. The
depth was 160 feet, and the boxes of gold
had to be won, at that depth, from a
small lazarette in the ships run to which
access was obtained through three decks
by the aid of tonite having an explosive
upward force. A German company also
had a try for the other box of 910000,
working on the basis of so per centum, no
cure, no pay, but the divers found the
depth too much for them and the salvage
was abandoned.
The dread of lightning coming in to the
home over q telephone wire will no longer
affect the nervous person. The Chicago
Telephony describes a new arrester that
can be mounted on a telephone or placed
on the line that comes into the building
that has never been adequately sup
piled; consequently this arrester was de-
veloped having in view these require
ments. This arrester is very compact.
being only three and three-eighths inches
high. 1t is covered with removable
glass top which protects every live wire
The construction is such that it can be
mounted on the top of telephone or
used as a main line arrester outside of
the building In protected place.
The theory upon which it depends for
it's arresting qualities is based on the
we'll known fact that lightning will jump
across an air space to an adjacent ground
rather than traverse even one complete
circle of wire.
The arrester is made up entirely of
non-inflammable material, namely, the
base of porcelain, spools of lava and
cover of glass. In this connection it.
should be noted that when these arresters
are placed on top of the telephone, which
is generally the housewives cupboard for
scissors. spectacles, etc., the glass cover
absolutely protects every hVe WIRE from
a ground or a short.
Everybody knows that an arc light Is
formed by causing an electric current to
pass between the points of two carbon
rods One of these Is called the positive
and the other the negative electrode, and
the current passes from the former to
the latter. Particles of carbon are car
ried on from the positive electrode until
it's end becomes cup shaped.