San Antonio daily light. [volume] (San Antonio, Tex.) 1886-1907, 1891-06-05
HOW SAFES ARE MADE
FlREPROOF MATERIAL is PLACED BE-
TWEEN IRON SHEETS.
James Conner, Type Founder, Made
the First Iron One in iS29-Many Kinds
of Mixtures Are Used for FilIing-Burg-
lar Proof Safes.


corners and across the top and front with
iron bands studded with nails. Iron plates
were eventually made to cover the outside
of the chest and nailed to the wood. The
foundation of the plan upon which fire
proof safes are still constructed was laid
by Richard Scott in 1901 The improve
ment previous to 1926 was to make the
chest of soft wood, in thicker body, soaked
in brine. After thoroughly soaking both
the inside and outside shells sheets of iron
were fastened inside and outside with
large nails or spikes.
The idea and principle was that the
moisture in the wood upon the application
OF heat would produce steam and prevent
the interior and its contents reaching a
temperature of 212 dogs. Below that point
paper of every description will be preserved
from damage either TO the fiber of the ma
terial or to the writing which may be upon
its surface. These principles of the steam
producing quality and the reliance upon
this quality is the principal element in the
manufacture of all safes of the present day
though different materials may be used to
produce the same result.
James Conner, a type founder of this
city, about 1892 invented an iron strong
plaster of Paris mixed with water Later the
shells were lined with sheets of mica past
ed on paper and filled with burned clay or
sawdust and charcoal. Plaster retained
the moisture successfully, but was so de
structive to the thin iron shells that its
use was abandoned. Conner allowed his
invention to lapse, and II man named Fitz.
gerald in 1913 obtained new letters patent
on the same kind of a safe.
SOME OLD SAFES.
William Mari, of London, in 1884, was
the first to patent a method of construction
for safes. In 1888 Charles Chubb, of the
same city, used cOucentrc Innings of iron
plates filed in between with wood ashes
or other slow conducting materials of
nature to retard the transmission of heat
In 1913 letters patent were granted to the
Messrs. Tam for the use of pounded alum
and gypsum, previously heated and cooled.
as a fire resisting medium. In 1910 Thorn
as Miner had patented plan to fill the
jacket, formed by the double plates, with
sawdust in which were packed number
of small tubes filled with an alkaline solu-
ton and Theoretically sealed, or crystals of
alum or soda combining from 10 to 60 per
cent. water crystalization.
In case of fire the safe heating tubes
would burst or the crystals would melt
and saturate with water the sawdust
Steam thus produced by the heat would
pass into the inner safe and protect its con
teEts, if inhammable, for long time
George Price, of Northampton, England
in 1855, tried the plan of coating metal sur
faces exposed TO the filling with compost
ton to prevent corrosion, and then used
powdered alum and sawdust as a filler
Previous to this, in lS49, dry plaster and
common grade of alum or potash alum was
found to he of value as a non-condnctor of
heat. Plaster was used for it's nOn-con
duc;Cr quality and alum for the large pro
portion of water it contains in crystaliza
ton. The same heat which produced steam
;.iso fused or d:sintegrated alum, releasing
the moisture and producing the requisite
steam qualities.
The principal argument that might be
used against this combination would be
that alum in fusing almost entirely disap
Fears. Thus vacuum is left, to take the
place of which there is nothing to support
the outer frame of the safe The outer
frame must remain intact in order to retain
the steam.
MODERN SAFES.
In another mixture of similar character
at this time was included marble dust and
the refuse of soda manufactures When
this material was heated it was supposed
to produce CarDOnic acid gas. The gas was
to suUduc or eXtinguish fire or flames in
ta- immediate vicinity by reducing the
temperature. Still another material used
as Il filler Was pulverized hydraulic cement
Wink, embraced the several qualities of the
plaster and alum.
This Material is a nOn-cOnductor of heat
ard contains water in large quantities
ITlike the dry plaster and alum it is a
.o.id, having Il crushing strength in itself
of several hundred pounds to the square
inch. The extraction Of the moisture by
any degree of beat that can possibly he
produced in an accidental fire leaves the
GIlng solid and intact. The volume is
neither increased nor decreased. so there is
no strain on the frame which covers it
Most Of the iireprCUi safes of the present
day are made of wrought iron plates aud
angles on the outer and inner frames The
USUAL thickness of the walls is from five
and bali to six inches. Combination locks
are used almost universally, yet locks are
TIE exception. The number of safes pro
duccd by the manufacturers has largely
increased in later years.
Burglar proof safes are distinct from
lireproof safes in material, construction
ana the object for which they are built
The walls are composed of high and low
grades Of steel, which, when tempered
viii resist the most powerful drill But
! it is an error to suppose that a safe which
provides security from the burglars drill
| is for that reason sufficiently protected
from burglars who are properly fitted for
an attack upon bank safe or vault.
Recent experience has demonstrated that
other methods are more expeditions, in
volving less risk for the operators, and are
| tl,-,, S,ra oartoiu Of Srrroacc