IMPROVEMENTS IN SAFES, CHESTS, BANK VAULTS, AND OTHER LIKE STRUCTURES
Year: 1870

page_text: LETTERS PATENT to John Henry Johnson, of 47, Lincoln's Inn
Fields, in the County of Middlesex, Gentleman, for the Invention
of "IMPROVEMENTS IN SAFES, CHESTS, BANK VAULTS, AND OTHER LIKE
STRUCTURES." -A communication from abroad by Theodore Hyatt, of
T
LT
PROVISIONAL SPECIFICATION left by the said John Henry Johnson
at the Office of the Commissioners of Patents, with his Petition,
on the 5th May 1870.
I, JOHN HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County.
of Middlesex, Gentleman, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN SAFES, CHESTS, BANK VAULTS, AND OTHER LIKE
STRUCTURES," a communication to me from abroad by Theodore Hyatt, of
the City of New York, in the United States of America, to be as.
follows:-
:-
This Invention has for its object the rendering of safes and other like
structures fire-proof, and the protecting of the same against corrosion,
and consists as follows:-With reference to what are known as 66 steam

page_text: safes," instead of resorting to some kind of mechanical contrivance to
ensure the water vessels against losing their contents, chemical means are
employed, the vessel is filled with just as large a volume of water as
could be used in its fluid state in combination with mechanical means,
and then the water is solidified by adding thereto just so much plaster of
Paris as will effect this without increasing its volume. Sometimes the
filling is put into the walls of the actual safe itself, in which case the
safe is made of galvanised iron in order to secure a non-oxidisable vessel
and water-tight soldered joints, the essential feature of this part of the
Invention being the constructing a safe of galvanized iron when filled
with solidified water as herein described, or with wet plaster or its
equivalent. In those cases where the filling is put into a separate
interior safe facility is afforded for making the outer one in a simpler
manner and in many cases more adaptable to certain required conditions,
as, for example, where a chilled iron safe is required or one of extra
burglar-proof character.
The main feature of this part of the Invention in this case is the
constructing a fire-proof safe where the wet filling is secured within an
air and water tight double walled interior non-oxidizable safe, while the
outer safe or strong box is the actual protection against burglary,
suitable provision being made for the escape of steam. When using a
series of vessels or tubes, such water vessels or tubes are to be filled with
water, which is prevented from escaping by being solidified, as already
described.
This Invention relates also to the production of a new combination of
heat resisting materials, and to a new method of applying the same
when employed for filling the spaces between the inner and outer walls
of fire-proof safes, bank vaults, and other like structures and doors for
the same. For this purpose it is proposed to use cans or vessels con-
structed of any non-corrosive material or materials of any suitable form
and size, containing gas or steam producing materials, and to place them
in any position between the inner and outer walls or shells of fire-proof
safes and other like structures, and to envelope and insulate them from"
such walls and from each other by means of a filling or packing of dry
non-heat conducting absorbent earth or earths, such earths being
combined in any proportions with any chemical salt or salts containing
water of crystallization. The vessels holding, gas or steam producing
materials are insulated from the external walls of safes and other

page_text: structures by means of the above dry compound.
It is also proposed
to insulate the vessel containing steam generating materials from the
interior walls or shells of book cases by means of the said dry compound,
and also to insulate the cans or vessels containing gas or steam producing
materials from each other by the same means.
Another part of this Invention consists in the use of asbestos when
combined with any steam or gas producing materials as a filling for fire-
proof safes and other like structures, also to the use of asbestos when
combined with any earth or earths as a filling for fire-proof safes and
other structures, or when combined with any earth or earths and any
chemical salt or salts containing water of crystallization as a filling for
fire-proof safes and other structures. It is further proposed to use
asbestos as described above when combined with cans or vessels con-
taining steam or gas producing materials as a filling for fire-proof safes
and other structures, and to use asbestos for lining to any desirable
thickness, the wall or walls of a safe or other structure on its interior
surfaces looking into the fire-proof chambers for the purpose of
insulating from such walls the principal or main body of filling com-
posed of any suitable material or materials that may be used for that
purpose.
Another part of this Invention relates to the production of a new
combination of asbestos with liquid or semi-liquid vapour or steam
generating materials for filling the chambers or spaces and the cans,
tubes, or vessels used in such chambers between the interior and exterior
walls or shells of fire-proof safes and other like structures, and doors for
the same.
In this case asbestos is employed in any suitable form or
condition when combined with any liquid or semi-liquid vapour or steam
generating materials, such as water or solutions of glycerine, gelatine, or
mucilage as a filling for fire-proof safes, and also as a filling for the cans,
tubes, or vessels used in such safes. It is also proposed to use asbestos
in this case when combined with any suitable earth or earths aud
liquids, semi-liquids, or solutions as above mentioned, as a filling for
fire-proof safes and as a filling for the cans, tubes, or vessels used therein,
or as a filling or lining for double shelled closets or book cases of fire-
proof safes. And further to use asbestos as an absorbent of liquids and
as an indestructible fibrous bond, ligament, or connecting medium for
binding, supporting, and uniting together the earth or earths employed
in a composition or filling for fire-proof safes and other structures.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said John Henry Johnson in the Great Seal Patent
Office on the 3rd November 1870.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County of
Middlesex, Gentleman, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Fifth day of May, in the year of our
Lord One thousand eight hundred and seventy, in the thirty-third
year of Her reign, did, for Herself, Her heirs and successors, give
and grant unto me, the said John Henry Johnson, Her special
license that I, the said John Henry Johnson, my executors, adminis-
trators, and assigns, or such others as I, the said John Henry Johnson,
my executors, administrators, or assigns, should at any time agree with,.
and no others, from time to time and at all times thereafter during the
term therein expressed, should and lawfully might make, use, exercise,
and vend, within the United Kingdom of Great Britain and Ireland,
the Channel Islands, and Isle of Man, an Invention for "IMPROVE-
MENTS IN SAFES, CHESTS, BANK VAULTS, AND OTHER LIKE STRUCTURES," a com-
munication to me from abroad by Theodore Wyatt, of the City of
New York, in the United States of America, upon the condition
(amongst others) that I, the said John Henry Johnson, my executors
or administrators, by an instrument in writing under my hand and
seal, should particularly describe and ascertain the nature of the said
Invention, and in what manner the same was to be performed, and
cause the same to be filed in the Great Seal Patent Office within six
calendar months next and immediately after the date of the said Letters
Patent.
NOW KNOW YE, that I, the said John Henry Johnson, do hereby
declare the nature of the said Invention, and in what manner the
same is to be performed; to be particularly described and ascertained
in and by the following statement, reference being had to the accom-
panying Drawings, and to the letters and figures marked thereon, that is
to say :-
The said Invention has for its object the rendering of safes and other
like structures fire-proof, and the protecting of the same against corro-
sion, and consists as follows:-
-

page_text: 66
Firstly. These improvements consist not only in the mode of con-
structing the shell or strong box with reference to its fire-resisting
qualities, but also in a new process for combining water with plaster
of Paris, by means of which while increasing the weight I do not
increase the volume of water. In this way I am enabled to practically,
surround the central space or cave with a wall of solidified water.
Plaster of Paris and water as usually mixed by safe makers is a hap-.
hazard combination as to proportions, the purpose being to have suffi-
cient water to "set" the plaster, but my combination is a scientific
one, in which plaster is used merely to solidify water, the difference.
between the methods being that whereas by the ordinary one but a per-
centage only of the compound which fills the entire space is water, by
my method the water actually fills up the entire space notwithstanding,
the addition of an amount of plaster which is equal to one-third the
weight of the water.
**
Fire-proof safes are of three kinds, dry safes," wet safes," and,
"steam safes." The first is filled with dry plaster and some salt. The.
second with plaster or its equivalent holding water by absorption, and.
the third has simply water contained in metal cases as the " filling.".
This makes a steam safe, but there is danger in a fire that the metal.
cases may become emptied of their contents by steam pressure or at any
time by leakage arising from accident.
The improvements under this head of the Invention apply to the
last-mentioned style of safe, for instead of resorting to some kind of
mechanical contrivance to ensure the water vessels against losing their
contents I employ chemical means. I fill the vessel with just as large
a volume of water as could be used in its fluid state in combination
with mechanical means, and then I solidify it by means of that quantity
of plaster that will do this without increasing its volume.
66
The following is the plan I pursue. I make the external shell or
'strong box'
in the ordinary way of making them as to strength.
Then to prevent its power of radiating heat when exposed to flame, as
it would do being iron, I line it on the inside with some good dry slow
conductor of heat, after the method pursued in constructing ordinary
"steam safes." I then make a series of water vessels out of copper or
other non-oxidizable metal, and shape them like bricks or long flat
tubes, so as to have them lic snugly together and form when in place a
complete lining to the safe. Each tube or vessel is formed of one con-

page_text: tinuous sheet as to three of its sides, the fourth being soldered on, so
that in a fire this one becomes loosened by the melting of the solder,
and thus allows the escape of its steam.
1
I make the filling of these tubes in the following way:---Taking the
_quantity of water necessary to fill the tube I weigh it, and then I take
of plaster of Paris a quantity equalling one-third the weight of the
water, which I add to the water. As it requires about twenty minutes
for the water to become solidified, it is necessary to occasionally stir
the mass to prevent the plaster from all settling to the bottom of the
vessel.
There is yet another way in which I reduce the principle of my
discovery to practice, viz. instead of filling the solidified water into
a series of vessels I use only one, and shape this exactly like the
external shell, so that when in position the inner one just fills the
place. This makes the construction in effect two safes, one within the
other, the outer representing the strength of the safe and the inner
one its fire-proof quality. This inner safe is made of copper or other
light non-oxidisable metal, is a double walled safe and water-tight.
The central space of this safe is the "cave," in which to keep the
effects which are to be secured against fire. The space within the
walls of this safe I fill with water and solidify it in the manner already
described. I have said that this inner safe exactly fills the outer one.
It is evident that it may be made smaller, and then the intervening
space between the two may be filled with some slow conductor, like
baked wood, fire-brick, or dried cement.
There is also still a third mode of reducing my discovery to practice,
which is as follows, videlicet, by making the "strong box" itself doubled
walled and of galvanized iron, water-tight, and filling the space within
the walls with solidified water as described.
In this mode of construction I provide a number of suitable apertures
for the escape of steam into the interior of the safe or
cave," and
these apertures I cover by thin metal plates soldered on, so that on
the melting of the solder the plates will drop off and let out steam.
Secondly. These improvements relate to the production of certain
new combinations of heat resisting materials, and a new method of
applying the same when employed for filling the spaces between the
inner and outer walls of fire-proof safes, bank vaults, and other
structures, and doors for the same.

page_text: One portion of this head of the Invention is more particularly
applicable to that class of safes in which the vapor or steam producing
materials, as water, water solidified with plaster, or any chemical salt
containing water of crystallization, are enclosed in hermetically sealed
cans or vessels, such cans or vessels usually being constructed of some
non-corrosive metal, glass, or earthenware, and of such form and size as
renders them most convenient, efficacious, and enduring when placed in
their position between the inner and outer walls of the safe or other
structure.
It is manifest the most perfect filling for fire-proof safes and other
structures will be that which is incombustible, non-conductive of heat,
and sufficiently absorbent to take up any moisture escaping from the
cans or vessels through imperfect construction or accidental injury.to
them, thus preserving the contents of the book case perfectly dry and
free from dampness and mould.
j
It is further obvious that the incombustible non-heat-conducting
materials for filling safes and other structures may also possess within
themselves a reserve force or power of giving off vapor or steam
under the application of heat to aid in preserving the contents of such.
structures.
To secure these valuable results I employ any dry non-heat-conducting
absorbent earth or earths combined and mixed in proper proportions
with any chemical salt containing water of crystallization; and in
practice I use one part of such dry salt. I prefer one part carbonate
of soda combined with two parts of dry earth or earths. Of such earth
I prefer sulphate of lime, but do not confine myself to these propor-
tions of salt and earth, as they may be varied to any extent found
desirable.
The cans or vessels containing the gas or steam producing materials I
make three-and-one-half inches thick, and of any suitable width and
length, and prefer to fill them with water solidified by plaster, as set
forth under the first head of this Specification.
I apply the above dry compound as a packing or filling between the
external walls of the safe and other structures, and the cans or vessels
containing gas or steam producing materials, so as to entirely insulate
them from said walls by interposing about two inches in thickness of the
packing between the cans and the external walls. I also insulate the
walls of the interior closet or book case from the vessels or cans by

page_text: interposing about one inch in thickness of the above fillings between the
cans and the interior walls of the book case, which dry non-heat-con-
ducting filling in this place not only serves to retard and keep back the
heat, but also prevents condensation of atmospheric moisture upon the
surface of the book case and its contents.
I also insulate the cans or vessels from each other by interposing in
each instance about one-half inch in thickness of the above-named
filling between them, which filling or packing in all cases operates as
an elastic bed or yielding cushion to protect and preserve the can or
vessels from injury by shocks or concussion.
A safe or other structure made on the above plan operates when
exposed to a.conflagration as follows, videlicet, the outer wall of filling
being composed of dry plaster and chemical salt containing water of
crystallisation, it acts as a non-conductor of heat by giving up in form
of vapor or steam the water of the salt, which coming in contact with
the plaster first sets or indurates it before passing off, and leaves this
wall of plaster filled with countless air cells that were formerly occupied
by the minute crystals of salt. This indurated honeycombed wall of
plaster still capable of absorbing a large quantity of moisture seizes the
vapor as it escapes from the cans of steam producing materials, and
retaining it in the network of cells prevents its rapid conduction out-
ward, thus prolonging its protecting power.
When the cans containing water solidified by plaster are exhausted of
their water by evaporation the plaster still remains in position and form,
constituting a protecting wall of porous material and non-conductive of
heat to the last degree.
Finally, after the protecting power of both the above-named walls is
totally expended there remains the inner wall of filling between the cans
and the book case to yield its vapour before destruction of the safe by
fire can be accomplished.
The Drawing annexed is a sectional plan of a safe constructed accord-
ing to this part of the said Invention.
A is the outer shell or case of iron; B is the interior wall or shell of
the book case; F is the cave in which the valuable books and papers to
be preserved from fire are placed; D, D, are the interior walls of dry
filling between the book case and cans or vessels, and between the cans
themselves; E, E, is the outer wall of filling between the cans and the

page_text: external wall or shell; C, 0, 0, 0, represent the cans or vessels or various
forms.
The iron safe being placed upright with the top end open, I proceed
to pack in the floor or bottom of the safe a layer of the above described
dry material about two inches thick and covering the whole space. I
then place the cans containing gas or steam-producing materials around
all sides of the safe, but leaving two inches of space between them and
the wall or shell of iron. When these are in position the can or cans
for the floor or bottom is let down between the upright ones to its place
and resting on the bed of dry material. I then cover this can one inch
deep with dry compound and put the book case in place resting on it,
leaving one inch of space between it and the cans around the sides.
I now commence to pack closely the vacant spaces between the outer
shell and cans, and between the cans and shell of the book case and
between the cans themselves with the above described dry material to
the full height of the cans, on the top of which, including the book case,
is packed the same dry material one inch deep. On this the top can is
placed extending over the book case to the outside of all the cans, the
spaces around all the sides and above the top of this last can are then
packed to the full height of the safe with the dry material, after which
the iron plate forming the top of the safe is fastened in its place and the
safe is completed and ready for usc.
The great advantage of this part of the said Invention consists in
making a safe that is perfectly dry at all times, thus avoiding all injury
to books and papers by dampness and mould, whilst at same time
having a superior non-heat-conductive wall containing two or three
times a greater quantity of gas or steam producing materials than any
other known materials, these materials being in the best condition and
combination to preserve a safe unharmed for longer time through a
conflagration than any hitherto discovered.
This head of the Invention further consists in the use of asbestos in
the production of a new combination of heat resisting materials for
filling the chambers or space between the inner and outer walls of safes,
bank vaults, and other structures and doors for the same, to prevent the
radiation of heat to the interior book case and destruction of its valuable
contents when the safe is exposed to fire..

page_text: For centuries asbestos has been known for its remarkable properties
as a non-conductor of heat and indestructibility by fire, yet heretofore
no application of this material to the construction of fire-proof safes has
been productive of any valuable practical result.
In carrying out this part of the said Invention I employ any of the
five following methods of preparing and applying the new combination
of heat resisting materials:-
First. I combine one part of ground or crushed asbestos with one equal
part of any chemical salt or salts in small crystals containing water of
crystallization, mixing them well together, and with this compound filling
closely the chambers or space between the inner and outer walls of the
safe or other structures.
Second. I combine one part of asbestos with one equal part of any
earth or earths, as Rosendale cement, or plaster of Paris, thoroughly
incorporated and applied as above described.
Third. I combine one part of asbestos with one equal part of any
earth or earths, and one equal part of any chemical salt or salts
containing water of crystallization, as alum, or sulphate of soda, mixing
these materials together and applying them as above mentioned.
Fourth. I use asbestos alone or combined with earth or earths and 2
chemical salt or salts containing water of crystallization as heretofore
described to insulate cans or vessels holding steam or gas producing
materials from the wall or walls of the safe or other structure in the
following manner:-After placing the cans or vessels in their proper
position in the safe, I then fill in or pack tightly with asbestos alone or 2
with either of the above named compounds all the unoccupied room or
space between the said cans or vessels, and the wall or walls of the safe
or other structures, as set forth in the first part of the second head of
this Invention.
Fifth. I use asbestos to form a superior non-conducting wall or walls 3
of about one inch or more in thickness next to and adjoining the inner
or outer shells or both of them of the safe or other structures for the
purpose of insulating the central or interior and main body of filling
from said wall or walls, thus protecting it from the early effects of heat
when the safe is exposed to fire..
3

page_text: In the above described compounds I do not confine myself to the
precise proportions stated of as bestos and earth, or earths and chemical
salts, as they may be varied to any extent found most effective in
practice.
According to another mode of using asbestos I propose to combine it
with liquid or semi-liquid vapor or steam generating materials for filling
the chambers or spaces, and the cans, tubes, or vessels used in such
chambers between the interior and exterior walls or shells of fire-proof
safes and other structures and doors for the same, when constructed for
the purpose of preserving books, papers, bank bills, coin, gold and silver
ware from injury or destruction by fire.
It has been found by actual experiment that asbestes will drink up or
absorb three times its own weight of water, which can then be solidified
or set by mixing with it plaster of Paris equal in weight to that of one-
third the asbestos used, and this combination is accomplished without
increasing its volume or bulk in the least degree.
Owing to the fibrous nature of asbestos it is enabled to perform a most
important function in the composition "or filling for fire-proof safes and
other structures when combined with any earth or earths such as
plaster of Paris, Rosendale cement, marble dust, or pipe clay, by acting.
as a bond or ligament to unite and bind such earths together in one
interlaced mass, upholding and supporting it at all times, thus preventing
any shrinkage or settling away of the fire-proof composition from the
walls of the safe during a conflagration, so that although every atom of
water may have been expelled by heat the walls of asbestos and earth still
retain their full form and dimensions, not permitting the existence of
any vacant or empty space within the cans or walls of the safe for
the heat to penetrate across to attack and destroy the book case and its
contents.
As an illustration of the above, the following experiment may be
referred to:-The Inventor took one hundred and thirty-five grains of
water, which completely filled a box two by three inches and one and
a half inch deep. This water being turned into a bowl and forty-five
grains of ground asbestos mixed with it, the water was absorbed, to
solidify which fifteen grains of plaster of Paris were incorporated with
the mass, which in ten minutes began to set, when the whole was
refilled into the same box, thus presenting the singular spectacle of a
box that was entirely filled by one hundred and thirty-five grains of

page_text: water, an incompressible element, now containing one hundred and
ninety-five grains, or nearly one-half more than its total capacity..
The above mass of fire-proof composition was placed in a stove oven,.
remaining there until all the water was expelled by heat. When taken
out it was found to retain perfectly its full form and size, and weighed
precisely sixty grains, the exact equivalents of asbestos and plaster used,
thus demonstrating that the whole one hundred and thirty-five grains.
of water existed in a free condition ready to be given off in the form of
steam when called upon by fire..
"
I will now describe the improved composition and the mode of using
the same in several forms, as employed by me in practice, first describing
the materials used, and how combined..
First. I take asbestos of any suitable form or condition, as slabs,
blocks, ground or crushed, and wet it to any desirable extent with any
steam producing materials, as water, or solutions of glycerine, gelatine,
or mucilage, but in all cases I prefer pure water alone.
Second. I take asbestos combined with any earth or earths, as
Rosendale cement, plaster of Paris, pipeclay, or marble dust, in the
proportions of two pounds of asbestos to one pound of earth (of which
earths I prefer plaster of Paris), and wet them sufficiently with water
or any of the steam producing materials heretofore mentioned.
Third. I combine asbestos with any chemical salt or salts containing
water of crystallization in proportions of three pounds of asbestos to two
pounds of the salts, of which salts I prefer Glauber's salts.
Fourth. I take asbestos combined with any earth or earths, and any 1
chemical salt or salts containing water of crystallization, as alum, sal-
sodo, borax, Epsom and Glauber salts (which last-named I prefer to
use), in the proportions of one pound of Glauber's salt to one pound of
plaster of Paris and one pound of asbestos, to be used in a dry condition,
or, if preferred, wet with proper amount of water or any of the steam
producing solutions described heretofore.
In the three fire-proof compounds lastly above set forth I do not
confine myself to the precise proportions of asbestos and earth or earths
and chemical salt or salts, as stated, as they may be varied to any extent
found most effective in practice.
· Having described the materials and their proportions as combined and
used in my new fire-proof composition. for safes and other structures, I.

page_text: will now describe several methods adopted for applying the same to
filling safes, bank vaults, and other structures and doors for the same:-
First. I construct a safe with inner and outer shells or walls of metal,
or the inside one of wood, and forming the framework of the book case,
leaving about six inches between the walls in all directions, and con-
stitutes the fireproof chambers of the safe. The joints and surfaces of
these walls looking into the fire-proof chambers are first well covered
with one or more coats of paraffine or any materials impervious to
water, to prevent oxidation of the metal and transmission of moisture
from the fire-proof composition into the book case to dampen and mould
its contents. This being done, either of the heretofore last-described
compounds of asbestos is then filled in closely between the walls until
no part is left vacant, the door also being filled in the same manner,
when the safe is finished and the remaining joints sealed up with some
waterproof materials to prevent evaporation.
Second. I make a safe with an external shell of iron, and then an
inner safe of gutta percha, india-rubber, or some, non-corrosive materials
like copper, and made with double walls about six inches apart to receive
the fire-proof composition, its shape being exactly like the external shell,
so that when in position it just fills the place. This makes the con-
struction in effect two safes, one within the other, the interior one being
filled compactly with either of the above described compounds of
asbestos. The inner safe may be made somewhat smaller than the outer
one, and the intervening space filled with any slow conductor of heat
like asbestos, plaster of Paris, or either of the non-conducting compounds
herein-before described under the second head of this Invention.
Third. I construct safes of iron having inner and outer shells about
six inches apart, the intervening space being occupied by cans or vessels
made of gutta percha, india-rubber, copper, or other non-oxidizable
material, and of such size and form as to fit respectively the top,
bottom, and each side of the safe. Or these vessels may be divided into
a series of smaller ones in shape, like bricks or long flat tubes, which
are filled with either of the heretofore described asbestos compounds and
hermetically sealed.
Fourth. I construct safes of iron with inner and outer walls or shells
about six inches apart, a portion of which space, usually one half, I
occupy with cans, tubes, or vessels placed in suitable positions and filled

page_text: with either of the heretofore described asbestos compounds, while the
remaining and unoccupied space between such vessels and wall or walls
is filled with any earth or earths, alone or combined with any chemical
salt or salts holding water of crystallization, as heretofore mentioned or
occupied by other cans or vessels containing water or other steam-pro-
ducing substances or asbestos alone.
'
Fifth. I sometimes construct the closet or book case with double shells
between which, as additional security against fire, I form a lining
of either of the heretofore described asbestos compounds or of asbestos
alone.
Having now described and particularly ascertained the nature of the
said Invention, and the manner in which the same is or may be used
or carried into effect, I would observe in conclusion that what I consider
to be novel and original, and therefore claim as the Invention secured
to me by the herein-before in part recited Letters Patent is,―
First. Constructing a fire-proof safe of galvanized iron rendered air
and water-tight, and filling the surrounding spaces with solidified water,
as herein described, or with wet plaster or its equivalent.
Second. Constructing a fire-proof safe where the wet filling is secured
within an air and water tight double walled interior non-oxidizable safe,
while the outer safe or strong box is the actual protection against
burglary, provision being made for the escape of steam as herein-before
described.
Third. The use of a series of vessels or tubes as a lining for safes
when such vessels or tubes are filled with water, which is prevented from :
escaping by being held therein by a chemical instead of a mechanical
contrivance, as herein-before described.
Fourth. The use of cans or vessels constructed of any non-corrosive
material or materials of any suitable form and size containing gas or
steam producing materials, when said cans or vessels are placed in any a
position between the inner and outer walls or shells of fire-proof safes
and other structures, and enveloped and insulated from such walls and
from each other by means of a filling or packing of dry non-heat-con-
ducting absorbent earth or earths, when such earths are combined in
any proportions with any chemical salt or salts containing water of
crystallization.

page_text: Fifth. Insulating the vessels holding gas or steam producing materials
from the external walls of safes and other structures by means of the
herein-before described dry compound.
Sixth. Insulating the vessel containing steam generating materials
from the interior walls or shells of a book case, by the means and for
the purposes herein-before described.
Seventh. Insulating the cans or vessels containing gas or steam pro-
ducing materials from each other by the means and for the purposes
herein-before described.
Eighth. The use of asbestos when combined with any steam or gas
producing materials as a filling for fire-proof safes and other structures.
Ninth. The use of asbestos when combined with any earth or earths
as a filling for fire-proof safes and other structures, in the manner and
for the purposes substantially as herein-before described.
:
Tenth. The use of asbestos when combined with any earth or, earths
and any chemical salt or salts containing water of crystallization as a
filling for fire-proof safes and other structures, in the manner and for the
purposes substantially as herein-before described.
Eleventh. The use of asbestos as described in either of the three fore-
going claims, when combined with cans or vessels containing steam or gas
producing materials as a filling for fire-proof safes and other structures,
in the manner and for the purposes substantially as herein-before
described.
Twelfth. The use of asbestos for lining to any desirable thickness, the
wall or walls of safes or other structures on their interior surfaces, looking
into the fire-proof chambers for the purpose of insulating from the said
walls the main body of filling, composed of any suitable material or
materials that may be used for that purpose, in the manner substantially
as herein-before described.
Thirteenth. The use of asbestos in any suitable form or condition,
when combined with any liquid or semi-liquid vapor or steam generating
materials, such as water or solutions of glycerine, gelatine, or mucilage,
and employed as a filling for fire-proof safes constructed in either of the
modes herein-before described, and also as a filling for the cans, tubes,
or vessels used in such safes.
Fourteenth. The use of asbestos when combined with any suitable
carth or earths and liquids, semi-liquids, or solutions, as above men-

page_text: tioned, and employed as a filling for fire-proof safes, when constructed
in cither of the modes herein-before set forth, and also as a filling for
the cans or vessels used in such safes.
Fifteenth. The use of either of the two foregoing described com-
binations of asbestos or of asbestos alone when employed as a filling or
lining for double-shelled closets or book cases of fire-proof safes.
Sixteenth. The use of asbestos as an absorbent of liquids and as an
indestructible fibrous bond, ligament, or connecting medium for binding,
supporting, and uniting together the earth or earths employed in a
composition or filling for fire-proof safes and other structures.
In witness whereof, I, the said John Henry Johnson, have to this
my Specification set my hand and seal, this Third day of Novem-
ber One thousand eight hundred and seventy.