A MODE OF KEEPING THE AIR IN CONFINED PLACES IN A PURE OR RESPIRABLE STATE, TO ENABLE PERSONS TO REMAIN OR WORK UNDER WATER AND IN OTHER PLACES WITHOUT A CONSTANT SUPPLY OF FRESH ATMOSPHERIC AIR
Year: 1842

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
REVELL VIGERS, of Russell Square, in the County of Middlesex, Esquire, send
greeting.
:
WHEREAS I did by petition humbly represent unto Her present most
Excellent Majesty Queen Victoria, that in consequence of a communication
from a foreigner residing abroad, I had become possessed of an Invention of
"A MODE OF KEEPING THE AIR IN CONFINED PLACES IN A PURE OR RESPIRABLE
STATE, TO ENABLE PERSONS TO REMAIN OR WORK UNDER WATER AND IN OTHER
PLACES WITHOUT A CONSTANT SUPPLY OF FRESH ATMOSPHERIC AIR," and Her said
Majesty, being willing to give encouragement to all arts and inventions which
may be for the public good, was graciously pleased by Her Royal Letters
Patent, under the Great Seal of the United Kingdom of Great Britain
and Ireland, bearing date at Westminster, the Seventh day of July (One
thousand eight hundred and forty-two), in the sixth year of Her reign, for
Herself, Her heirs and successors, to give and grant unto me, the said Wil-
liam Revell Vigers, my exors, adñiors, and assigns, Her especial license, full
power, sole privilege and authority, that I or they, by myself or themselves, or
by my or their deputies, servants or agents, or such others as I or they should
agree with, and no others, during the term of fourteen years from the date of
the said Letters Patent, should and lawfully might make, use, exercise, and
vend the said Invention within that part of Her said Majesty's Dominions
called England, Her Dominion of Wales, and the Town of Berwick-upon-
Tweed, and in all Her Majesty's Colonies and Plantations abroad, and in-the..
A

page_text: Isles of Man, Jersey, Guernsey, Alderney, and Sark, in such manner as to me,
my exors, adñiors, and assigns, shall seem meet, and as that I or they shall
enjoy the whole profit and advantage arising by reason of the said Invention
during the said term of fourteen years; and for that end Her said Majesty
requires and strictly commands all Her subjects whatsoever, within England,
Wales, and Berwick-upon-Tweed, and the Colonies and Plantations, and Isles
of Man, Jersey, Guernsey, Alderney, and Sark, aforesaid, that they shall not,
neither directly nor indirectly, make, use, or put in practice the said Invention,
or any part thereof, nor in anywise counterfeit, imitate, or resemble the same,
nor make any addition thereto, or subtraction therefrom, whereby to pretend
himself or themselves to be the inventor or inventors thereof: And whereas the
said Letters Patent also contain a proviso obliging me, the said William
Revell Vigers, particularly to describe and ascertain the nature of the said
Invention, and in what manner the same is to be performed, by an instrument
in writing under my hand and seal, and to cause the same to be inrolled in
Her Majesty's High Court of Chancery within six calendar months next and
immediately after the date of the said Letters Patent, as in and by the same
(reference being thereunto had) will more fully and at large appear.
NOW KNOW YE, that in compliance with the said proviso, I, the said
William Revell Vigers, do hereby declare that the said Invention is described
and ascertained in manner following, and by the aid of the three Sheets of
Drawings hereunto annexed, that is to say:
The said mode of keeping the air in confined places in a pure or respirable
state, to enable persons to remain or work under water and in other places with-
out a constant supply of fresh atmospheric air, is performed by absorbing (in
the manner herein-after described) from the air in confined places the carbonic.
acid gas, wherewith such air will always become more or less contaminated in
consequence of the breathing of men or animals, or burning of candles, lamps,
or gaslights, or burning of fires of wood, charcoal, coals, turf, or other fuel, or
in consequence of any evolution of carbonic acid gas, or any explosion of gun-.
powder which may take place in the said air in confined places: And further,
in case such air is to be kept in a pure state, by supplying (in, the manner
hereinafter described) to the said air, from which the carbonic acid gas has
been absorbed as aforesaid, as much oxygen gas as may be requisite for
replacing the oxygen which may have been abstracted from the said air during
such breathing or burning, or such evolution, or explosion, as aforesaid. The
absorption of carbonic acid gas from air in confined places which has become
contaminated with such acid gas is effected by forcing the air to pass, in manner
herein-after described, in a current or currents in contact with an alkali ren-

page_text: dered caustic by means of recently burned quicklime, so as to be capable of
absorbing carbonic acid from the air which is so brought in contact with such
caustic alkali and quicklime, which are to be mixed together in water; or,
such quicklime may be used alone without alkali, and either in a pulverent
state and slacked, or the quicklime may be mixed with water; and the restora-
tion of oxygen to air in confined places, which is become deficient thereof, is
effected by allowing oxygen gas to escape gradually into such air from some kind
of close vessel, into which a large quantity of oxygen gas has been previously
compressed with great force, and retained therein under strong compressure;
or, otherwise, by means of potash previously prepared in the state of peroxyde
of potassium, that is, potassium charged with an additional portion of oxygen
beyond what is contained in caustic potash. Fragments of such peroxyde
being put into the water will emit or give out the said additional portion of
oxygen in the state of gas; or, otherwise, by means of chlorate of potash, or
of peroxyde of manganese, or either or both those substances, which, being
submitted to heat in a suitable apparatus, will (as is well known) emit or give
out a portion of oxygen in the state of gas; and the oxygen gas, whether pro-
ceeding directly from such substances, or from compression in close vessels, as
aforesaid, by mixing with the air in confined places which has become deficient
in oxygen (but which is already freed from carbonic acid gas,) will restore the
said air to a pure or respirable state. The removal of carbonic acid gas from
the air in confined places is the most important part of the Invention, and that
alone will be sufficient for keeping the air in a respirable state in places which,
although they may be confined places, nevertheless contain a large quantity of
confined air, in proportion to the number of persons or animals breathing, and
of lights or fires burning in such confined air, such, for instance, as crowded
theatres, courts of justice, and other public places, also the lower parts of the
interior of large ships, the cells of prisons, wards of hospitals, and apartments
of sick persons, also in extensive excavations of mines, in all which cases the
ordinary means of ventilation can be practised with some effect. In still more
confined places, and where such ventilation is difficult and inefficient, the restora-
tion of oxygen will be important, as well as the removal of carbonic acid, such;
for instance, as long and small galleries of deep mines, and in diving apparatus,
or submarine boats or vessels, wherein persons are to remain and work under
water, also in crowded transport ships and hospital ships, where the quantity
of confined air is small in proportion to the persons, animals, lights, or fires,
breathing or burning, in such confined air.
Respecting the absorption of carbonic acid gas from the air in confined places,
the said air is to be put in motion by some means which will produce à current

page_text: thereof, and such current is to be passed in contact with the caustic alkali and
quicklime or with the quicklime. The apparatus to be employed may be con-
structed in various ways, and certain apparatus which is in common use for
other purposes will afford models for the manner in which the apparatus for
the purposes of this Invention may be constructed. For instance, almost any
kind of bellows or blowing machines which are commonly used for blowing air
in musical organs or into furnaces will serve as models for the apparatus
which is to be used for putting the air into motion in a current; and almost
any kind of purifying apparatus which is commonly used in gas-works for
purifying inflammable gas for illumination, by causing a current of such
gas
to pass in contact with quicklime, in order that impurities may be thereby
absorbed from such gas, will serve as models for the corresponding part of the
apparatus which is to be used for causing a current of the air of confined
places to pass in contact with caustic alkali and quicklime or with the quick-
lime in order that carbonic acid may be absorbed from such air. The
purifying apparatus for gas is of two kinds; one, wherein quicklime mixed
with water to the consistency of milk or cream (and hence called milk or
cream of lime) is used; the other, wherein dry quicklime, in a state of coarse
powder, is used, for absorbing impurities from the gas; the apparatus being
in either case adapted for bringing the gas effectually in contact with the
quicklime. The caustic alkali and quicklime which are (or the quicklime
which is) to be used according to the present Invention for absorbing
carbonic acid from the air in confined places, may be mixed with water so as
to be in a liquid or semi-liquid state, in which case the gas-purifying apparatus
with milk or cream of lime may serve as a model for the apparatus to be
used for the purpose of this Invention; or otherwise, the said caustic alkali
and quicklime, or the said quicklime, may be used in a state of coarse dry
powder, in which case the gas-purifying apparatus with dry lime may serve
as a model for the said apparatus. It is not intended to direct that the
apparatus, which is above referred to as being in common use, should be adopted
without alteration for the purposes of this Invention, but only to intimate that
the kind of apparatus above referred to will serve as models, after which (with
adequate alterations) suitable apparatus for the purposes of this Invention may
be constructed by any competent engineer or constructor of machinery, and
hydraulic, of pneumatic, or steam, or gas apparatus, and who must exercise a
judicious discretion in adapting the apparatus to each particular kind of situation
in which the same is to be employed. The Invention may be practised in the
simplest manner with very ordinary apparatus; for instance, a common pair of
leathern bellows for domestic use in kitchens, but strongly made and in good

page_text: condition so as to blow forcibly, will serve for producing the required motion
and current of the air in a confined place, and an ordinary wooden pail or
bucket, or earthen pan, or other like vessel, will serve to contain the caustic
alkali and lime and the water wherewith the same is to be mixed, or the quick-
lime and water, and by means of which water the ingredients are to be
reduced to a liquid state. The quantities of those ingredients may,
in general,
be reckoned at the following rate for each person who is to breathe the air
of the confined place in question; videlicet, four ounces of the potash of com-
merce of the best quality, and twenty ounces of newly burned quicklime, and
about twelve pounds of fresh water; or otherwise, two pounds of newly burned
quicklime, and about sixteen pounds of fresh water without alkali. The
said ingredients or ingredient being mixed up, the water in the bucket or
other vessel and the nosle of the bellows being prolonged by an iron pipe
bended downwards, the end of that pipe is to be immersed in the liquid, so as
to descend nearly to the bottom of the vessel, and then by blowing strongly
with the bellows, the air of the place wherein the bellows are situated will;
by action thereof, be blown downward some depth into the liquid, nearly to'
the bottom of the vessel and by its buoyancy the air will ascend again through
the liquid in bubbles so as to be passed very effectually in contact therewith
and with the caustic alkali and quicklime (or with the quicklime) which is
mixed with the water and which is kept mixed by the agitation occasioned by
the bubbling of the air through the mixture. The lime which is thus employed
having, by its recent burning, been deprived of carbonic acid lias a 'strong
tendency to absorb carbonic acid, and when the lime is mixed as aforesaid
with the potash of commerce, which contains carbonic acid, the latter is.
absorbed by the lime, so as to deprive the potash of its carbonic acid and
render it caustic, and the mixture of caustic potash and lime and water will,
owing to the quantity of lime it contains, or the lime, if that alone is used.
with water, will have a strong tendency to absorb carbonic acid from the air
which is brought into contact with it. The water acts as a medium for
bringing the potash and the lime into a state of intimate admixture in order
that the lime may operate on the potash to absorb the carbonic acid therefrom
and render the same caustic, and also that the mixture of caustic potash and-
lime, or that the lime, if that alone is used, may operate on the air which is
passed in a current through the mixture of caustic potash and lime and water
or through the mixture of lime and water by means of the bellows, in order to
absorb from the air any carbonic acid which that air may contain, and which
will be very effectually done by continuing the operation of blowing with the
bellows. Wherefore, as fast as the air in the confined place is contaminated.

page_text: by carbonic acid, which is formed by the breathing of the persons who
are shut up in such confined place, the air so contaminated being, by
action of the bellows, drawn into them and then forced out from them
down into the liquid, will, by the contact therewith, which results from the
air reascending in bubbles through the liquid, have all the said carbonic
acid absorbed from the air by the caustic potash and lime, or by the lime, and
the air which rises up from the surface of the water will be in a respirable
state as respects freedom from contamination by carbonic acid gas. The opera-
tion aforesaid may be carried on during some hours before the absorbent
property of the liquid mixture will become so much diminished as to require a
renewal of the liquid; with the proportionate quantities of potash and lime
and water (or of lime and water) already mentioned, the liquid will last for
four hours. The capacity of the vessel wherein the liquid mixture is contained
should be at the rate of about two gallons for each person. The bellows
should be of such capacity, and should be worked with such rapidity, as to
pass at the rate of about one cubic foot of the air per minute for each person
through the mixture. And note, for each candle or ordinary lamp which is
to burn in the air contained in the confined place nearly as much should be
allowed of each of the proportionate quantities herein-before mentioned as
would be required for the breathing of one person. In mixing the aforesaid
ingredients it will be best to begin by putting the quicklime into the vessel,
and mixing it well with about one-third of the intended proportion of water, and
after that mixture has been effectually made, then to add the remainder of the
water and the potash, in case of potash being used as well as lime, and make a
complete liquid mixture of the whole. The simple manner, above described,
of operating, although it might be effectual if the proportions aforesaid are duly.
observed, would not be so convenient as with a more complete apparatus. The
operation will be facilitated if the air is blown in a continuous current, for
which purpose the bellows may be double, such as are used by blacksmiths, or
two single bellows may be used to blow alternately. The bellows commonly
used in musical organs are a very suitable model for the construction, and par-
ticularly the double acting bellows of such organs as are termed barrel organs,
wherein the bellows are actuated by means of a crank on an axis, which is
turned round with a continuous rotative motion by a winch or turning handle,
the bellows being strongly made, so as to blow air more forcibly than is usually
required for organs. The nosle pipe, by which the air blown by the bellows is
conducted down into the liquid mixture, as above described, should be divided.
into several branches, in order that the current of air may be divided into as
many streams, so as to distribute the air throughout the liquid mixture, and.

page_text: that it may ascend in small bubbles through the liquid mixture, and be brought
in effectual contact therewith.
Sheet 1 of the Drawings hereunto annexed contains three Figures repre-
senting an apparatus which is conveniently arranged for including everything
requisite in a small compass. It operates by means of two bellows A, B,
worked with alternate motion by double cranks a, b, radiating in opposite
directions from a horizontal axis D, which is turned round with a continuous
rotatory motion by a winch handle E. The whole apparatus is contained in a
box G, H, the interior of which is divided by a horizontal partition F into an
upper and a lower compartment. The upper compartment G contains the two
bellows A, B, side by side, and the lower compartment H is lined with zinc or
lead, or tinned copper, to serve as the vessel or cistern for containing the
liquid mixture of ingredients whereby carbonic acid gas is to be absorbed as
herein-before mentioned from the air which is blown by the bellows down into
the liquid, and which rises up again through the same in bubbles. Each
bellows consists of a lower board d, which is fixed on the partition F, and an
upper moveable board e, which has two inverted valves f, f, in it, opening
downwards and shutting upwards by aid of slender springs to counterbalance
the weight of the valves. The leather surrounds both boards, and is united. to
the edges of both. From the lower board d of each bellows three or more
pipes g, g, g, descend through the partition F nearly to the bottom of the
cistern H to convey down the air which is blown by each of the bellows in
three or more currents, and thereby distribute that air in the liquid. A narrow
flat passage h ascends through the horizontal partition F, and stands up between
the two bellows to convey the air up through the upper compartment G, and
through the cover M thereof, after the air has ascended through the liquid in
bubbles; m, m, are holes through which air is admitted into the upper com-
partment G as fast as the bellows require. K, Figure 3, is a screw plug,
which can be removed to open an entrance into the cistern H for filling and
emptying the same. The liquid mixture should be prepared as herein-before
<directed in another vessel, and after being well mixed may be poured in at K,
and the plug closed. The axis D is sustained at each end in bearings affixed
to the sides of the box, and its two cranks a, b, operate in horizontal slots i, i,
formed in the two upright rods k, k, which are fastened at their lower ends to
the upper moveable boards e, e, of the bellows, and are retained at their upper
ends in guides 1, l, which are sustained by the cover M of the box. The said
upper boards e are retained between fixed upright guides n, n, Figure 2, to
cause those boards to move truly up and down, and preserve their horizontal
position. When the handle E is turned round, one of the cranks a or b raises

page_text: the upper board e of one bellows, which therefore draws in air of the confined
place through the inverted valves f, f; at the same time, the other crank
depresses the upper board e of the other bellows, which thereupon forces the
air that the said bellows contains down through the pipes g, g, g, into the
liquid mixture nearly to the bottom of the cistern H, and from thence that air
ascends through the liquid in bubbles to the surface, and the carbonic acid gas
is absorbed from it in so ascending, and then the same air passes up through
the flat passage h, and escapes from the apparatus at the upper aperture
thereof, see h, h, Figure 1. The foregoing examples will suffice to explain
how bellows may be applied in apparatus for the purposes of this Invention.
Figures 4, 5, 6, Sheet II., are three Figures which represent an apparatus
with one blowing cylinder or double-acting air pump, in lieu of two bellows.
H is the cistern for containing the liquid mixture of ingredients, as before. In
the cover F of that cistern the blowing cylinder A, B, is fastened. It has a
moveable piston e, Figure 6, fitted to move up and down in it by a piston
rod k, which passes through a stuffing box in the cover d of the cylinder; the
piston has no valves in it; fis a valve which opens inwards to admit air to pass
through the opening p into the upper part A of the cylinder above the piston c,
whilst the piston is descending, and at the same time the air contained in the
lower part B of the cylinder beneath the piston e is forced down through the
opening q, and the descending pipe g into the liquid mixture near to the bottom
of the cistern H, and therefrom the air ascends in bubbles through the liquid,
as already described. When the piston e is moved upwards, the valve f closes
and another valve r opens, to admit air, which passes down through the opening
g into the lower part B of the cylinder below its piston c. At the same-time
the air in the upper part A of the cylinder above the piston e is forced out
through the opening p and down the descending pipe s, near to the bottom of
the cistern H, and therefrom the air descends in bubbles through the liquid.
The piston e is moved alternately up and down by means of a cross head i at
the upper end of the piston rod k and side connecting rods L, L, which go
down from the two ends of that cross head to two cranks a, Figure 5, on a hori-
zontal axis D, which is turned round with a continuous rotary motion, and the
cranks move the piston alternately up and down. The air which has passed
up through the liquid in bubbles then passes up through four holes t, t, in the
cover F, Figure 4, of the cistern H. The section, Figure 6, shews a perforated
false bottom P, which is fixed horizontally near to the real bottom of the
cistern H, and the descending pipes gand s pass down through the false bottom
P, so as to convey the air beneath that bottom, where the air spreads itself and
ascends in numerous small bubbles through the holes wherewith the bottom P

page_text: is perforated. By that means the air is greatly divided and brought very
effectually in contact with the liquid. A similar perforated false bottom might
be used in the apparatus Sheet I., or in any other apparatus herein-before
described.
go
Figure 7, Sheet II., is another apparatus, with a double-acting air pump,
which is placed by the side of the cistern H for containing the liquid mixture.
e is the piston; f, the valve through which air is drawn into the upper part A
of the cylinder when the piston is descending, and then the air in the lower
part B beneath the piston e is forced out through the valve q into the ascend-
ing pipes and the horizontal pipe V which leads to the cistern II, and therein
the air descends from that pipe V through several branches 9, 9, I, which
down obliquely in the liquid contained in the cistern H, so as to distribute the
air therein, and from the lower end of each of the branches 9 the air descends
in bubbles through the liquid. When the piston e is moved upwards, the
valve r opens to admit air into the lower part B of the cylinder beneath the
piston e, and at the same time the air in the upper part A above the piston e
is forced out through the valve u into the same horizontal pipe V before
mentioned, whereby the air is conveyed, as before stated, through the branches
g into the liquid in the cistern H. If that cistern has a close cover F, then
the air which has ascended through the liquid and become freed from carbonic
acid will be conveyed away through a pipe or passage t. The apparatus has
been herein-before described as if it were always situated within the confined
place, the air of which is to be operated upon by the apparatus, in which case,
the apparatus being surrounded by the air upon which it is to operate, that air
is drawn into the apparatus through certain holes or valves in it, and de-
livered out again from the apparatus through other holes. In many cases it-
will be more convenient to have the apparatus at a distance from the confined
place, the air of which is to be operated upon by the apparatus; for instance,
in crowded theatres, and other public places where there would not be room
for an apparatus in the confined place, and more particularly in the long and
narrow galleries of deep mines. In the latter case it will be best to place the
apparatus at the bottom of the engine shaft, where power can be readily obtained
from the engine for working the blowing machinery of the apparatus, and the
apparatus may, in such case, be on a large scale, to serve for keeping the air
in a respirable state in several confined places at the same time by one opera-
tion, the air being conveyed from each such confined place to the apparatus
through long air pipes, which join to the valves f and r of the blowing cylinder,
as shewn at W and X, Figure 7, so that the air brought by the said pipes W
and X will be taken into the cylinder through those valves at the upper part A

page_text: and the lower part B alternately. The pipe W may bring air in one direction
from one confined place and the pipe X may bring air in a different direction
from another such place, and either or each pipe W and X may have branches
for bringing air from more than one confined place, or from as many as is
required. Or instead of two pipes W and X, the air may be brought to the
apparatus by one long conveyance pipe, as shewn by the dotted lines w, which
pipe may communicate by an upright pipe x with both the valves f and r. The
said long conveyance pipe w and the several valves and passages belonging to
the blowing cylinder and the pipe V should be of adequate size for giving free
passage to the air through them. The usual proportions which are observed
in the construction of the blowing cylinders, with their pipes, valves, and
passages for blowing air into furnaces, may be followed. The area of the un-
interrupted passage for the air through each of the several pipes, valves, or
passages should be at least one-sixteenth of the area of the piston in case of a
passage which will have to convey or admit through it the whole of the air
that is blown at one time by the motion of the piston; or, in case of the whole
of the air being divided and having to pass through two or more passages, the
united areas of those passages should be at least one-sixteenth of the area of
the piston. The cistern H may be at a distance from the blowing cylinder in
cases when that will be convenient, the horizontal air pipe V being in all cases
extended from the blowing cylinder to the cistern H. The air which has
passed through the liquid mixture in tlie cistern H, and thereby become freed.
from the contamination of carbonic acid gas, and which air passes out from
the cover of the cistern H at t, may be conveyed from t by a pipe with
branches therefrom, if required to return to the confined place or places from
whence the said air had been previously brought by the conveyance pipes
W and X, or w, whilst it was in a contaminated state. The cistern II may,
if convenient, be situated at some intermediate place between the blowing
cylinder and the confined place or places, the air of which is to be operated upon
by the apparatus. In such case the conveyance pipes W and X, or w, from
the confined place or places may require to be as long as the united length of
the pipe V and the pipe which proceeds from t to the confined place or places.
As to the relative situations of the blowing cylinder and the cistern H with
respect to each other, and with respect to the situation or situations of the
confined place or places, the air of which is to be operated upon, those relative
situations may be adapted to suit the circumstances of each particular case,
provided adequate conveyance pipes are established as aforesaid. In some
confined places, as mines, wells, tunnels, and other subterranean excavations,
carbonic acid gas is often evolved upon the strata of the earth, independently.

page_text: of and in addition to that which may be produced by the respiration of men or
animals, and the burning of lights or fires in such confined places; also, when
gunpower is used for blasting rocks carbonic acid is evolved in considerable
quantities by the explosion of the gunpowder. In such cases the magnitude of
the apparatus, and the quantity of the caustic alkali and lime (or of the lime),
which is supplied to it, must be augmented beyond the proportions berein-
before stated, but how far such augmentation should be carried must depend
upon the particular circumstances of each case. In all cases it will be advan-
tageous to have an apparatus of ample size; and if larger than would be
necessary, according to the proportions herein-before stated, the operation upon
the air in confined places will be equally well or better performed, and that
without waste or loss of the ingredients, in consequence of the larger quantities
thereof in the apparatus, because the larger quantity of ingredients will last a
longer time in an efficient state without changing or renewing. In cases
when the air in confined places is subject to be greatly contaminated with
carbonic acid gas from any of the causes aforesaid, then it will be best to use
the returning conveyance pipe, which proceeds, as before mentioned, from the
upper part of the cistern H at t to the confined place or places, in order to
return the air which has passed through the liquid mixture in the cistern, and
become freed from carbonic acid, to the said place or places. In other cases
such returning conveyance pipe may be dispensed with, and the air which is
discharged from the cistern H may be left to make its own way back to the con-
fined place or places through the galleries or passages which lead thereto, which
can very well be done without a returning conveyance pipe in case there is no
contamination going on at the time in such galleries or passages by evolution
of carbonic acid gas, or by combustion of fire of any kind, or by explosion of
gunpowder. But in case such contamination is going on, then the returning
conveyance pipe before mentioned should be used from the cistern H att to
the confined place or places wherein it is desired to keep the air in a respirable
state, so as to enable persons to remain or work therein. The long conveyance
pipes W and X, or w, as also that which proceeds from the cistern. H at t, do
not of necessity require to be strong metal pipes, because there is very little
compressure of air in them, wherefore, they may be trunks of wood or flues of
brickwork, tiles, or stone, or any such kind of passages for conveying currents
5 of air as are commonly used, or as can be used for the conveyance of air
in ordinary modes of ventilation.
Sheet III. contains several Figures representing an apparatus in which the
required current of air is produced by means of a revolving wheel or drum. A,.
whereof the rim. is hollow, and divided into compartments a, b, c, d, e, f. The

page_text: lower part of the drum A is immersed in the liquid mixture contained in the
cistern H, and which liquid tends to displace air from those compartments
c, d, e, which are for the time the lower half of the drum, in consequence of the
liquid entering at openings which are made for that purpose in the circum-
ference of the drum at g, h, i, and through them the liquid fills the said lower
compartments, the air which is displaced from those compartments passing out
therefrom at openings j, k, l, and ascending in bubbles through the liquid
contained in the cistern H. The other compartments b, a, f, which are
for the time the upper half of the drum A, empty themselves of the liquid
they had previously contained through openings o, n, m, at which the liquid can
run out laterally, and as fast as it does so, air can enter through the openings
r, q, p, into the said compartments b, a, f. The drum is mounted on a
horizontal axis D, which passes out through a stuffing box in one side of the
cistern H, and by means of a winch handle E, on the end of the axis, the
drum can be turned round within the cistern, and as it revolves, those com-
partments which were the upper half of the drum become the lower half, and
vicê versâ. Those compartments which go down one after another are full of
air, which they carry down into the liquid in the cistern H, and the liquid
entering at some of the openings, such as g, h, i, into the said compartments
as they go down, displaces the air therefrom through some of the openings,
such as j, k, l, and the air so displaced ascends in bubbles through the liquid in
the cistern H, and the air is brought effectually in contact with the liquid in
being so displaced, and in so ascending in bubbles through the liquid; and
those compartments which come up one after another are full of the liquid
which they bring up above the level at which the liquid would otherwise stand
in the cistern H; and the liquid running out through some of the openings,
such as m, n, o, from those compartments as they come up causes air to be
drawn into the said compartments through some of the openings, such as
p, q, . And by the arrangement of the apparatus the air so drawn in is that
air of the confined place or places which is contaminated with carbonic s
acid gas, and which requires to have such acid absorbed from it; for that air
enters through openings w, w, w, in the cover of the cistern H, immediately
over the drum, so to as to gain admittance through the openings and r
into those compartments a and 6 of the drum, which are at the time going up
out of the liquid, whereby the said compartments a and b become filled with 3
the air which is contaminated, in readiness for that air to be carried down
in such compartments into the liquid when those compartments a and b go
downwards in their turn in consequence of the revolution of the drum A. The:
contaminated air which is admitted at w, w, w, into the upper part of

page_text: the case wherein the drum A is contained, is kept separate by a partition
V, X, X, X, V, in that case from intermixture with the air which is
contained in the lower part of the same case immediately above the sur-
face of the liquid contained in the said lower part, and which lower part
5 constitutes the cistern H. The edge of the said partition V, X, X, X, V,
applies as closely as possible to the two flat sides of the drum, as shewn by
dotted lines at X, X, X, Figure 9, and also to the exterior circumference of
the drum on each side thereof at V, V; and by means of a strip of felt, or
leather, or india-rubber, applied on such partition X, V, with the edge of that
felt, or leather, or india-rubber overhanging the edge of the partition, and
applying in contact with the sides, and with the circumference of the drum,
a sufficiently close junction is effected (without obstructing the revolving
motion of the drum) to prevent any material escape upwards of the air which
has passed out from the openings j, k, l, and which has ascended therefrom
in bubbles through the liquid in the cistern H, and which air has thereby
become freed from carbonic acid; but the said air remains beneath the partition
V, X, X, X, V, by which it is prevented from going up to the upper part of
the case, where the openings w, w, w, are, and the said air ascends by an
ascending passage t, which is provided for it, and by which it escapes upwards
and goes to mix with the air in the confined place; or if that place is at a
distance the air is conveyed thereto by a pipe proceeding from the passage t,
in the manner already described respecting Figure 7. In some cases it may
be desirable that the apparatus such as herein-before described should be
rendered self-acting, so as not to require a continual attention for giving motion
to the bellows or other parts whereby the current of air is caused. In many
cases the apparatus, when it is of large size, as for mines, may be worked by
a steam engine or other mechanical power when the same can be conveniently
obtained. But in cases of using such apparatus in diving bells or apparatus,
or other very confined places, the bellows or blowing cylinder, or revolving
drum, may be actuated by means of spring clockwork or wheelwork of.
suitable strength and adequate power for the purpose, in the same manner
as is frequently done for actuating the bellows in musical barrel organs, and
which spring wheel work being wound up will continue to keep up a continual
motion of the bellows for sometime without attention, until another winding-up
of the main spring is required; the motion of such wheelwork being regulated.
n the usual manner of such spring clockwork, by a revolving fly turned
apidly round by a worm wheel and endless screw. In other cases the same
ffect may be obtained by means of wheelwork actuated by a weight with
ulleys and a cord wound up around a barrel, in the manner formerly used in

page_text: roasting jacks for turning the spits whereon meat was roasted. And, note,
soda of commerce of the best quality may be substituted for potash, the soda
being used in the same manner as herein-before directed respecting potash, but
a rather larger quantity of soda may be advisable beyond the quantity of
potash herein-before mentioned.
Respecting the restoration of oxygen gas to air in confined places,
when such air may have become deficient therein, and after such air has
been freed (by the means herein-before described) from contamination of
carbonic acid gas. For this purpose large quantities of oxygen gas may
be forcibly compressed into strong metal vessels, wherein such gas may
be securely retained under a strong compressure; and such a strong vessel or
vessels so charged with compressed oxygen gas, being carried into the air in
the confined place, may have a cock in such vessel very slightly opened, so as
to emit a small efflux of the oxygen gas to mix with the air which is deficient
in oxygen. The opening of the said cock must be regulated to suit each par-
ticular occasion, and so as to emit just so much oxygen gas and at such a rate
as is required by the air in the confined place for restoring it to a pure state,
but no more than that. The gas pumps and apparatus for compressing the
oxygen gas into such strong vessels and the vessels themselves, with the cocks
thereof at which the oxygen gas is to be emitted, may be the same as are well
known, and as have been formerly extensively practised in London for what
was termed portable gas lamps. The inflammable gas obtained from the
destructive distillation of oil was for that purpose compressed into such vessels,
and then they were sent out to dwelling houses for the purpose of giving
artificial light by the combustion of a small jet of the gas, which by opening
a cock in the vessel was permitted to escape from its confinement in that vessel
into the open air; all which was the same course of proceeding as is required
for the purposes of this part of the present Invention, except as to the com-
bustion of the effluent gas, and the substitution of oxygen gas for the oil gas,
and also as to the object which was to produce artificial light, but in the
present case it is to supply any deficiency of oxygen that there may be in the
air contained in confined places. The apparatus and mode of operating for
such portable gas being well known it is not necessary to enter into any more
particular description. The oxygen gas should be compressed in such vessels
several atmospheres, so that a vessel may contain from ten to fifteen times the
quantity that it would contain without compression. Another mode of obtain
ing a supply of oxygen for the purpose aforesaid is by means of the peroxyd
of potassium, which substance is potassium combined by artificial means with
an additional proportion of oxygen beyond that which is contained in causti

page_text: potash, but such additional proportion of oxygen is very ready to make its
escape in the state of oxygen gas. So long as the peroxyde of potassium, after
being duly prepared, is kept securely inclosed in glass bottles with ground
stoppers, it will retain its extra proportion of oxygen, and remain in the state
of peroxyde; but on withdrawing small fragments of such peroxyde from the
said bottles and dropping the same into water, oxygen gas is disengaged with
an effervescence, and ascending from the water mixes with the air above that
water. This being performed in the air contained in the confined places
will restore oxygen gas thereto, the quantity of peroxyde which is so used
being regulated according to the deficiency of oxygen that is required to be
made up.
Another mode of obtaining a supply of oxygen gas for the purpose
aforesaid is by means of chlorate of potash, which is a chemical substance well-
known and easy to be procured, and which being put into a glass or an iron
retort and heated by fire or by the flame of a lamp, will give out oxygen
gas, which may be emitted into the air in the confined place so as to mix:
therewith. One and a half ounces of chlorate of potash being thus treated
will restore as much oxygen to the air of a confined place, as will have been
abstracted by the breathing of one person during the space of one hour in the
confined air; and if the chlorate of potash is mixed with about half as much by.
weight of peroxyde of manganese, the disengagement of oxygen gas from such
mixture by heat in manner aforesaid, will be much accelerated. And another
mode of obtaining a supply of oxygen gas for the purpose aforesaid, is by.
means of peroxyde of manganese, which is a substance well known and easy to
be procured, and which being put into an iron retort and strongly heated by.
fire, (at least to a red heat,) will give out oxygen gas, which may be emitted
into the air in the confined place so as to mix therewith, or the oxygen gas so
given out may be conveyed from the retort by a suitable pipe or pipes into a
a gasometer or gasholder, or into gasometers or gasholders, in order to be
reserved therein until wanted; and the gas so reserved may be let out from
such gasometer or gasholder, or gasometers or gasholders, through a suitable.
pipe or pipes, and stop cock or cocks, into the air in the confined place, so as
to mix therewith. About thirteen and a half ounces of such peroxyde of man-
ganese, being so treated, will restore as much oxygen to the air of the confined.
place as will have been abstracted therefrom by the breathing of one person
during the space of one hour in the confined air. And note, when oxygen gas.
is to be forcibly compressed into strong metal vessels as herein-before men-.
tioned, the oxygen gas which is to be so compressed may be obtained from the
peroxyde of manganese in manner aforesaid, and as that mode of obtaining:
oxygen gas is well known and commonly practised, it requires no further direc-;

page_text: tions for practising the same.
The retort, with its fire-place place and
gasometer or gas holder, for procuring oxygen gas in that manner, may be
situated in the confined place, whereof the air is to be kept in a pure or
respirable state if it is practicable or convenient to do so, or in some place
contiguous to such confined place as may be the case in some mines, or the
retort, with its fire-place and gasometer, may be situated in some place at a
distance from the said confined place, and the oxygen gas may be conveyed
from the gasometer by pipes to the said confined place, and emitted there,
through cocks in small jets, in the manner already mentioned respecting the
emission of oxygen gas from vessels wherein such gas has been compressed.
Respecting the keeping of air in confined places in a pure or respirable state
to enable persons to remain or work under, water, and in other places, without
a constant supply of fresh atmospheric air, common atmospheric air is to be
compressed into strong metal vessels of the same kind, and in the same
manner as herein-before mentioned respecting oxygen gas, and also in the
same manner as was the practice of compressing for portable gas, such a vessel
or vessels strongly charged with atmospheric air being carried into the air con-
tained in the confined place, it or they will afford a supply of air by merely
opening the cock or cocks for the purpose of mixing with the air in the con-
fined place, in, such quantity as may be necessary for assisting to keep the air
when so mixed in a respirable state. In case of such confined place being
deep under water, as, in, a diving bell or diving apparatus, wherein the air is
confined by the columnar pressure of the water, so as that the air will be
thereby kept in a state of compressure within the confined place, then any com-
pressed air which may be supplied from such close vessel or vessels as aforesaid,
in order to mix with the air in the confined place, will be retained in that con-
fined place so as to become a permanent addition to the quantity of air previously
contained therein.
Figures 14 and 15, Sheet II., are a vertical section and a horizontal plan
of a diving bell, which is constructed with strong chambers annexed to it,
and forming part of it, for containing common air, which is to be strongly
compressed into those chambers, and contained therein under compressure,
for the same purpose as would be accomplished by the strong vessel or vessels.
above mentioned, for the shape of the vessels is immaterial, provided they are
sufficiently strong to resist the elastic force of the compressed air, and air-tight,
so as to avoid leakage. A in both Figures is the interior of the diving bell,
being the confined place wherein the persons are to remain and work; B, B,
are the strong air vessels, one at each end of the bell for containing compressed
air; they are of such a form as will cause the exterior form of the whole bell

page_text: to be an oblong, with pointed ends, as is shewn by the plan, Figure 15,
whereby it is adapted for keeping more steady in a current of tide water than
if it had no such pointed ends. C, C, are spaces below the two air vessels for
the reception of ballast of lead, which can be put into or withdrawn from those
spaces through openings into those spaces from the lower part of the interior
A of the bell; b, b, are the air cocks, by opening which, the compressed air
can be let out of the air vessels B, B, to give an extra supply into the interior
A of the bell; E, E, are the iron links, and F the shackle by which the
weight of the whole is suspended; when such a bell is to be used, the two
strong vessels B, B, are first charged with air, which is strongly compressed
by means of forcing air pumps until a compressure of several atmospheres is
attained. The bell, with the persons in its interior A, is then let down into
the water, and as it descends the air in it is compressed into less and less
space by the columnar pressure of the water, and the water rises up in the
lower part of the bell, but by opening the air cocks b, b, an additional supply
of compressed air is admitted from the air vessels B, B, into the interior A of
the bell, and the addition so made to the quantity of air previously contained
therein will expel the water from the interior. In such manner, by regulating
the opening of the two air cocks b, b, the interior A of the bell can be kept free
from water. Note.-The usual means of supplying air to the interior of a
diving bell when it is sunk under water, may be also resorted to in order to get
the same filled or partly filled with air when it is first let down, and in that case
the compressed air in the two air vessels B, B, will be reserved as a further
supply, and they will hold out so much the longer for not having been used in
the first instance. When the bell has got down into the water to the depth
to which it is intended to descend, and the interior of the bell is so filled with
the air that the water is wholly kept out from it, and as soon as the air that is
confined in the bell begins to be contaminated with carbonic acid gas, then the
operation of absorbing sucli carbonic acid gas from the air which is confined in
the bell is to be performed with any of the apparatus herein-before described
that shewn in Sheet I. or Sheet III. being most convenient; and that operation
is to be continued at such rate as will absorb the carbonic acid gas as fast as
the same is produced by the breathing of the persons in the bell, and the burn-
ing of the lights they use therein, so as to keep the air that is confined in the
bell in a respirable state, as far as the continual removal of the contamination
of carbonic acid gas will do so. But in time, the abstraction of oxygen from
the air, by long continuance of the said breathing and burning, and formation
of carbonic acid gas, may operate to impair the fitness of the confined air for
B

page_text: respiration; and then, if a portion of such confined air is let out from the bell
by a cock, and if that portion is replaced by letting out a supply of compressed
air from the air vessels B, B, the confined air will be improved by such partial
change; or, the deficiency of oxygen gas in the confined air may be supplied
from the use of a. small. quantity of the peroxyde of potassium, in manner
herein-before described; or, the deficiency of oxygen gas in the confined air
may be supplied from the use of a small. quantity of chlorate of potash, or a
mixture of chlorate of potash with peroxyde of manganese in manner herein-
before described; or, a supply of oxygen gas may be let out from a strong
vessel which has been previously charged therewith, and kept in a state of
strong compressure. The section, Figure 14, shews how a portion of the
upper part of each air vessel B, B, may be partitioned off at r,.r, to serve as
strong vessels which may be charged with oxygen gas under strong compres-
sure before the bell is let down into the water, at the same time and in the
same manner as the large air vessels B, B, are charged with common atmo-
spheric air; s, s, are the cocks through which the required supply of oxygen,
gas is to be admitted from the said vessels 2, r, into the interior A of the bell,
and the opening of those cocks must be. regulated to emit just such an eflux
of the oxygen gas as will make up the deficiency of oxygen in the air that is
confined in the bell, but not more than that. The form of the vessels which
are to be charged as aforesaid with common air or with oxygen gas, is
immaterial.
Mode of preparing the peroxyde of potassium, which is to be used in the
manner.herein-before explained, for furnishing or restoring oxygen gas to
the air in confined places, when that air has become deficient in oxygen in
consequence of the breathing of men or animals therein, or the burning
of lights or fire in such air, and which air has been already freed from
carbonic acid gas, by the means herein-before described: Take a crucible
of platinium, which may be lined with silver, the cover of which fits on
very tight and closes the crucible hermetically, except that the said cover
(which may be also lined with silver). is furnished with a tube, also of
platinium, which may be covered with silver and lined with silver, or may be
made of silver of about one-third of an inch in diameter or.bore, and which
tube is passed down through the cover and is made tight therein, and the
lower end of which tube descends interiorly to within a short distance of the
bottom of the crucible. The upper end of the same tube (which end projects
externally above the cover) is furnished with a screw joint, by which it can be
joined to a silver pipe or tube, for conveying oxygen gas from a gasometer or

page_text: gasholder to the the interior of the crucible at the lower part of that interior.
The said cover is also provided with a safety valve, which opens from within
outwards, and which safety-valve is loaded, so that it will open with a certain
degree of pressure. Fill the said crucible three-fourths full with caustic
potass, prepared in a state of purity, with the aid of alcohol, according to the
well-known process practised by chemists for that purpose, and described by
writers on chemistry. To the screw of the aforesaid tube, which rises above
the cover of the crucible, join the silver tube, which, as before mentioned, com-
municates with a gasometer containing oxygen gas; then; having placed the
crucible in a suitable furnace, raise the temperature of the crucible and its con-
tents to a red heat, and after watery vapour ceases to be expelled and to make its
escape through the safety valve; then begin to cause a stream of the oxygen'
gas to pass from the gasometer or gasholder through the silver tube, so as to
enter the crucible with a sufficient pressure to enable the gas to overcome the
resistence of the melted mass at the bottom of the crucible, and wherein the
lower end of the upright tube will be immersed; the oxygen gas will thereby be
brought in contact with the caustic potash, under suitable conditions as to
temperature and fusion, for causing the potash to absorb the oxygen gas and to
combine with oxygen so absorbed until the caustic potash is converted into
the state of peroxyde of potassium. The operation is to be kept up and the
crucible is not to be removed from the furnace until due trial has been made,
by plunging into the contents of the crucible a silver rod (which may be intro-
duced through the hole into which the safety valve is fitted, when that valve is
removed, and which rod must be withdrawn instantly), and until after it is
found by such trial that the substance which adheres to the said rod presents a
greenish yellow colour. When the operation has been continued until the
potash has attained that colour, then the substance within the crucible is to be
allowed to cool until it hardens; and then, before it is completely cold, it is to
be reduced to fragments, which are to be preserved in glass bottles, perfectly
dry, and closed with stoppers fitting perfectly air-tight. When a few such
fragments of peroxyde of potassium are taken out of such bottles and
dropped into fresh water in a shallow vessel situated in the confined place
where the air requires a restoration of oxygen (that air having been previously
freed from carbonic acid gas), such fragments will emit oxygen gas with an
effervescence, and that gas rising above the surface of the water and mixing
with the air in such confined place will restore to that air the oxygen gas
wherein it was deficient, or part of what was so deficient.
Having now described the said improvements I, the said William Revell

page_text: Vigers do hereby declare that the new Invention, whereof I claim the
exclusive use to have been granted to me by the said Letters Patent, consists
in the following particulars, that is to say,―
Firstly, the mode herein-before described of keeping the air in confined
places in a pure or respirable state by causing such air to pass in a current
in contact with caustic alkali and quicklime, or with quicklime alone, without
alkali, whereby carbonic acid will be absorbed from such air, and by continu-
ance (as herein-before described) of so passing the air in such confined
places in a current in contact as aforesaid and thereby absorbing carbonic acid
from the said air as fast as carbonic acid may be produced by the breathing
of men or animals, or the burning of lights or fires in such air, or by the
explosion of gunpowder, or the evolution of carbonic acid gas therein, so
as to mix with and contaminate such air, the said air may by such continual
absorption of carbonic acid gas from it be kept in a respirable state provided
that the quantity of such air is sufficient in proportion to the number of the men
or animals breathing (or of the lights and fires burning therein, or to the
explosion of gunpowder or the evolution of carbonic acid gas therein) and in
proportion to the duration of such breathing (or burning or explosion or
evolution) to occasion no greater deficiency of oxygen in such air than can
be tolerably endured.
Secondly, the modes, herein-before described, of restoring to the air in.
confined places, after such air has (by the other modes herein-before described)
been freed from the contamination of carbonic acid gas, so much oxygen as
may be deficient in the said air; or part of that which may be so deficient. The
said modes being either to let out into the air in such confined places so as
to mix therewith a small efflux of oxygen gas from some suitable close vessel, as
herein-before described, wherein a great quantity of oxygen gas has been
previously compressed and forcibly retained therein under such compression, or
else, as herein-before described, to put fragments previously prepared of
peroxyde of potassium into water, in order that they may give out oxygen
gas to mix with the air in such confined places, or else to subject chlorate of
potash, or a mixture of chlorate of potash and peroxide of manganese, to heat
as herein-before described, in order that the same may give out oxygen gas
to mix with the air in such confined place, or else to subject peroxide of
manganese to heat, as herein-before described, in order that the same may
give out oxygen gas to mix with the air in such confined place.
Thirdly, the mode herein-before described of letting out into the air in
confined places, so as to mix with such air, a copious eflux of common atmo-

page_text: spheric air from some suitable strong vessel or vessels, wherein a great
quantity of such common air has been previously compressed, and wherein
the said common air is retained under strong compressure, so as by such
eflux of common air from such strong vessel or vessels to make a considerable
addition to the quantity of air that is contained in such confined places, in
order that, by such addition, the said air may be kept in a respirable state, and
which addition to the air may become a permanent addition to the quantity
thereof in case of the confined place being deep under water, and therefore
so subjected to the columnar pressure of the water as to cause compression of
the air in such confined place as in a diving bell, for instance; and such
permanent addition to the quantity of air which is enclosed and retained under
compression in such confined place, will, together with the aid of the first, or of
the first and the second modes of keeping the air in a pure or respirable state,
enable persons to remain or work under water in such confined place without
a constant supply of fresh atmospheric air other than that which is derived
by eflux of compressed air from the said strong vessel or vessels according to
this third article of the Invention; but, in cases where the air in the confined
place is not forcibly retained therein by a columnar pressure of water, or
otherwise, but can escape therefrom, if pressed to do so, then the said addition,
which is made by such eflux of compressed air from a strong vessel or vessels
as aforesaid, will not become a permanent addition to the quantity of air
contained in such confined place, because such addition so made by such eflux
will occasion an equal quantity of the air previously contained in such confined
place to pass away or escape therefrom; and, in such case, although no
permanent addition is made to the quantity of air contained in the confined
place by eflux of compressed air from a strong vessel or vessels according to
this third article of the Invention, nevertheless, a considerable change will be
made in the air in such confined place so as to render the same more
susceptible of being kept in a pure or respirable state by operation of the
first, or of the first and second articles of the Invention.
In witness whereof, I, the said William Revell Vigers, have hereunto
set my hand and seal, this Seventh day of January, One thousand eight
hundred and forty-three.
W. R. VIGERS. (L.S.)

page_text: AND BE IT REMEMBERED, that on the Seventh day of January, in the
year of our Lord 1843, the aforesaid William Revell Vigers came before our
said Lady the Queen'in Her Chancery, and acknowledged the Specification
aforesaid, 'and 'all and every thing therein contained and specified, in form
above" written. And also the Specification aforesaid was stamped according
to the tenor of the Statute made for that purpose.
Enrolled the Seventh day of January, in the year of our Lord One
thousand eight hundred and forty-three.