The Wichita daily eagle. [volume] (Wichita, Kan.) 1890-1906, 1891-04-01
HOW SAFES ARE MADE.
FIREPROOF MATERIAL is PLACED BE-
TWEEN IRON SHEETS.

James Conner. Type Founder, Made
the First Iron Gne in 1S29-Many Kinds
of Mixtures Are Used for Filling-Burg-
| lar Proof Safes.
The earliest style of safe known was
made in heavy oak or other hardwood
boxes or chests. They were bound on the
| 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 1925 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 degs. 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, type founder Of this
city, about 1899 invented an iron strong
box with double shell, having as a filling
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. Connor allowed his
invention to lapse, and a man named Fitz-
gerald in 1S43 obtained new letters patent
on the same kind of safe
SOME OLD SAFES.
William Mari, of London, in 1884, was
the first TO patent method Of construction
for safes. In 1888 Charles Chubb, OF the
same city, used concentric Innings of iron
plates filled in between with wood ashes
or other slow conducting materials of
nature to retard the transmission of heat.
In 1S43 letters patent were granted to the
Messrs. Tam for the use of pounded alum
as q fire resisting medium. In 1S4O Thorn
as Miner had patented plan to fill the
jacket formed by the double plates, with
sawdust in which were packed a number
of small tubes filed with an alkaline solu-
ton and hermeticauy sealed, or crystals of
alum or soda combining from 40 to 20 per
cent. water crystaEzation.
In case of fire the safe heating tubes
hr,- ~ ha .,
and saturate with water the sawdust.
Steam thus produced by the heat would
pass into the inner safe and protect its con
tents, if infammable, for a long time
George Price, of Wolverhampton, England.
in 1855. tried the plan of coating metal sur
faces exposed TO the filing with compost
tion 10 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 be of value as a non-conductor OF
heat Plaster was used for its uon-con-
ductor quality and alum for the large pro
portion of water il contains in c-ystaliza-
ton. The same heat which produced steam
also fused or disinteSrated alum. releasing
the moisture and producing the requisite
steam qualities.
Ac tudN might ES Z
used against this combination would be
that alum in fusing almost entirely disap-
pears. Thus vacuum Is left, to take the I
place Of which there i nothing TO support
the outer frame OF the safe The outer
frame must remain intact in order 70 retain i
[ ne steam.
MODERN SAFES
In another mixture OF similar character +,
at this time was incladed marble dust and i
the refuse OF soda manufactures When i
this material was heated it was supposed 4
to produce caFbonic acid gas. The gas was
10 subdue or exJingsIish fire or flames in
the immediate vicinity 6y reducing the /.
temperature. Still another material aseei 4
as q filler Was puIverized hydraulic cement
which embraced the several qualities OF the /
plaster and alum
This material Is a uoE conductor ot heat
and contains water n large quantities
Unlike the dry plaster sad alum i i g
solid. having 6 crushing strength II itself
OF several hundred pounds 70 the square
inch Ths extraction Of the moisture by
any degree ot SaAs shAs can possibly De
.-e6aee6 in an aeeid1nsA FIRE leaves TIE
filing soiid sni insaA The volume Is
reitheT increased ner der-=ase6. So there Il