The Portland daily press. [volume] (Portland, Me.) 1862-1921, 1894-03-10

OF the time lock as the DufSlaF line
locks are used in the Treasury Depart
ment and one of them is constant OBJ
ject of interest to visitors at the bureau
of engraving and printing. There is
time lock in the cashiers Office in the
Treasury Department, and one morning
some years ago the government suspend
ed payment for an hour because the
cashier had made a mistake IN seGtlng
the clock in the vault. At the end OF
that hour the doors of the vault swung
open automatically and Uncle Sam re-
sumed business at the old stand.
Four Clocks to Vault.
The average visitor at the bureau OF
engraving and printing, knowing the I'M
certainty of clock work from personal
experience, "wants-t to know" what would
happen if the clock spring should break
or the mechanism should be thrown out
of order while the vault is locked. All
of that has been provided for i'll modern
construction. The time lock now has
no one. but two, three or four clocks
in train. II one or even two or three OF
them should get out Of order slmultane-
ously, there would still be. the fourth to
open the vault door in the morning, and
to save the owner the necessity OF DUR
glarizing his own vault The posslblllty
of four carefully inspected clocks getting
out of order within few hours of each
other is so small that 1t is not considered
except in its relation to the burglar.
The jar OF an explosive used by burglar
might throw the clocks out of order.
This would make the burglars success
more doubtful, but it would net be an
unmixed blessing. TOR the owner OF the
vault would be out several thousand
dollars breaking into his vault So this
contingency is provided for in some cases
by mounting the clocks on springs.
Where spindles are still used (and they
are used in majority of the safes and
vaults constructed) they are sometimes
made in two parts, each passing nail
through the door at different points ana
connecting in the middle of the doors
thickness by a system of small gears
In another construction the spindle is
made of series of small cylinders and
larger disks along a common axis, on
the theory that the removal OF sucn
piece of work will be more difficult THAN
the removal of straight spindle. But
doctors disagree" very widely on the
subject of spindles. One maker uses
spindle of large size and heavy construc-
ton in the belief that an increase In
size will make entrance by this point
more difficult; another makes MS spin
die as small as possible in the belief that
the smaller the spindle the less useful
the spindle hole to the burglar.
The Effect of Nitro-GIycerine.
The most vulnerable part of a vault
now is the edge of the door. 1t is al
most impossible to obtain an absolutely
tight joint, one which will be impervi-
GUS to liquid explosives. The old method
of attack was by powder blown into the
stack of the vault door. As the con-
struction of these doors became more
perfect this was made impracticable.
Then the gentle burglar turned his at
tention to other explosives, and today he
uses nitro-glycerine. Nitro-gylcerine
when warm runs as freely as water. Ii
the crack of a door is not absolutely
tight the nitro-glycerine will find some
small lodging place in it. When exploit
ed it rips off the door, tears off its outer
layers or opens a space where larger
charge of explosives can be used: II the
Joint is too we'll fitted to permit the use
of nitro-glycerine and the vault is In an
isolated place where powerful explosives
can be used dynamite is laid against
weak spot and well tamped. Its explo-
sion either makes an opening or weakens
the walls or door SO that tools or other
explosives can be used to advantage
Win Il RudrduUCO 1lSSAAOilA
for operation, set of burglars can enter
a modern vault in one to eight hours
The shortest process is usually by the
use of explosives, and 1T has been found
that the high explosives are singularly
local in effect and produce very little
sound. Hammer and sledge are often
used, though burglars prefer boring,
with the use of a blow pipe to draw the
temper of the steel attacked. But the
modern construction renders this some
times extremely difficult because of the
high conductIvity of iron and the close
contact of the cold steel adjacent. Bur
glars seldom attempt to make holes of
more than an inch in diameter. and the
heat from the small fame which can be
introduced through such hole is quick
~ dissipated. Sometimes the burglar
bores through the soft metal and breaks
the intervening sheets of hard metal
wit the blows of a hammer removing
the metal by piece meal. 1t is estimated
that an expert with finely tempered tools
will work through an inch of vault all
in an hour. 1t sometimes happens,
though, that an lnexpert burglar aoan-
dons job after penetrating the outer
Iayer of steel because his poorly tempered
fools were all dulled in the attempt.
Sometimes a burglar finds it compare
lively easy to strip safe or vault. If he
can cut through the outer casing along
a line the wedgInS OH OF SneeG aLtef
sheet is a better method of attack than
drilling. A large and well built safe
has been completely destroyed by this
process in four hours of steady work,
with the use of sledge, cold ch1sels and
wedge. Recognizing the fact that a
principal danger is from striking"
steel makers say that they furnish
rather poor quality of steel to safe and
vault men. In the construction of the
new treasury vaults, though, it is likely
that only the best quality steel will be
used.
Dealers in safes and builders of vaults
have their little trade tricks, and one
of the most familiar of them is to get
piece of work from some rival establish
ment, bore holes in it and exhibit it as
a proof of the insecurity of the other
mans work. This proves nothing to the
exhibitors advantage, because it has
been shown by experiment that every
substance used in safe and vault con-
struction can be drilled. Even Frank
Unite" which was regarded in 1879 as al
most, if not quite. invulnerable. has
been drilled at the rate of an inch an
hour But the ordinary experiment with
materials take into consideration the
conditions under which the burglar must
,rorly What woujd he unite easy to az.