CERTAIN IMPROVEMENTS IN MANUFACTURING AND PURIFYING COAL GAS, AND IN TREATING A RESIDUAL PRODUCT OF SUCH MANUFACTURE; ALSO IMPROVEMENTS IN PREPARING MATERIALS TO BE USED IN THE PURIFICATION OF COAL GAS
Year: 1847

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, RICHARD
LAMING, of Clichy la Garenne, near Paris, in the Kingdom of France,
Chemist, send greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Royal Letters Patent under the Great Seal of Great Britain, bearing date at
Westminster, the Fourth day of November, in the eleventh year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto me, the said
Richard Laming, Herespecial licence, full power, sole privilege and authority,
that I, the said Richard Laming, my executors, administrators, and assigns,
and such others as I, the said Richard Laming, my executors, administrators,
or assigns, should at any time agree with, and no others, from time to time
and at all times during the term of years therein mentioned, should and.
lawfully might make, use, exercise, and vend, within England, Wales, and the
Town of Berwick-upon-Tweed, my Invention of "CERTAIN IMPROVEMENTS IN
MANUFACTURING AND PURIFYING COAL GAS, AND IN TREATING A RESIDUAL
PRODUCT OF SUCH MANUFACTURE; ALSO IMPROVEMENTS IN PREPARING MATERIALS
TO BE USED IN THE PURIFICATION OF COAL GAS;" in which said Letters Patent
is contained a proviso obliging me, the said Richard Laming, by an instru-
ment in writing under my hand and seal, particularly to describe and ascertain
the nature of my said Invention, and in what manner the same is to be
performed, and to cause the same to be inrolled in Her Majesty's High Court
Price 8d1

page_text: of Chancery within six calendar months next and immediately after the date
of the said in part recited 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
Richard Laming, do hereby declare that the nature of my said Invention, and
the manner in which the same is to be performed, is particularly described and
ascertained in and by the following description thereof, reference being had to
the Drawings hereunto annexed, and to the letters and figures marked thereon,
(that is to say):
The first part of my Invention which relates to improvements in the manu-
facture of coal gas, consists in improvements in the construction of furnaces used
for manufacturing gas,and has for its object to economize fuel, while at the same
time the destructive heat of the fireplaces is lessened. These advantages are
obtained by restraining the combustion of the fuel in the fireplaces so as to
convert the same into carbonic oxide gas, which is burnt into carbonic
acid (after it leaves the fireplace) by means of air heated by the products of
combustion in their way from the oven to the chimney.
In the accompanying Drawings I have shewn various views of one method
of carrying this part of my improvements into effect, as applied to two sets of
retorts, consisting of two rows, each placed back to back, and five retorts in
each bench or set. It will, however, be clearly seen that my improvements
are equally applicable to a single row of retorts, and to benches containing
more or less than five retorts.
Fig. 1 in the Drawings represents a longitudinal section taken through the
double set of retorts in the line N, O, P, Q, of Fig. 3, and shewing the retorts
in section, and the flue or chimney between them; Fig. 2 is a transverse ver-
tical section through the retorts, fireplace, and flues, for heating the air that is
supplied to the carbonic oxide-generated in the fireplace; Fig.3 is a horizontal
sectional view taken through the whole apparatus in the irregular line shewn at
A, B, C, D, E, F, of Fig. 1; and Fig. 4 is another horizontal section taken in
the line I, H, K, of Fig. 2. In all the Figures I have used similar letters of
reference to denote corresponding parts.. a, a, a, a, is the main flueinto which
the gaseous products of combustion pass from the smaller flues and ultimately
into the chimney; b, bisa centre wall, placed between the two rows of retorts
forthepurpose of separating them from each other other; and c, c, are other walls
of separation for the purpose of dividing the sets or benches from each other.
d, d, is the retort arch or oven for enclosing each set or bench of retorts;
and e, c, are the retorts arranged in sets of five. f, f, are the fireplaces,
which are each surmounted by an arch h, as seen best in the transverse section,

page_text: Fig. 2. The arch his rather more distant than usual from the firebars g, g,
and has side openings made therein (as seen in Fig. 2), for the purpose of
conducting the gases generated in the fireplace f to the lateral flues i, i, i, in
which the carbonic oxide is burned and converted into carbonicacid by means
of hot air that is heated in the hot-air flues o, o¹, o2,03,04, and o5, by the heated
products of combustion, which, after acting upon the retorts in the manner.
hereafter explained, descend by the passages j,j, and heat the air flues o, o..
When the carbonic oxide is converted into carbonic acid by the heated air.
that issues through the openings 9, 9, leading from the air flues o, o, into
lateral passages i, i, the heated products of combustion pass from the lateral
passages i, i, into the long flues r, r, r, r (see Figs. 2 and 4), from whence.
they ascend up the long vertical passages 7, *, into the arch or oven d, d,
where they reverberate and act upon and heat the retorts e, e, e, e, e, the sides of
the retorts having been left exposed for this p purpose. From the arch d, d,:
the heated gases pass down the flues j, j (as seen best in Fig. 1), to the.
chamber in which the air flues. o, o, are situated, the air in which becomes
thereby heated,as before mentioned. The flues,j,finally terminate in a common
flue k, which conducts the products of combustion through the opening 1, to.
the main flue a, a, as seen at the left-hand side of the longitudinal section,:
Fig. 1, and from thence to the chimney. The draught of the fireplace may
be regulated by means of a damper m, which is adapted to the opening 1,.
access to which is afforded by the covered well n, so that the damper may be
easily worked by a rod. The hot air flues o, o, may be composed either of
earthenware or iron pipes. The air enters the pipes cold by thatone marked o,
in Fig. 2; it passes along this latter to its opposite end, when it enters the
pipe o¹; advances along this pipe, and ascends by the junction pipe o2, into a
third flue o3; passes along this latter to its opposite end; from whence it enters
the fourth flue ; and having advanced along this flue, it ascends by the junc-
tion pipe o5; and is finally discharged in a heated state into the longitudinal:
distributing gallery p, p, from whence it issues through the orifices q,q, into the
lateral passages i, i, where it mixes with the carbonic oxide, which quickly.
becomes converted into carbonic acid. When using apparatus constructed in
the manner above set forth and described, I have generally found it desirable
to heap up the coke- upon the fire-bars to the depth of from fourteen to
eighteen inches. I regulate the combustion of the coke by means of the
damper m, and I mix more or less hot air with the inflamed carbonic
oxide in the flues i, i, by allowing more or less cold air to enter by the
pipe o. It is calculated that in furnaces of the ordinary construction the
temperature is about 1500 degrees of the Centrigade thermometer, when

page_text: the temperature of the retorts is only 1000. As, however, by my improve-
ments I am enabled to produce the greatest heat in the immediato vicinity
of the retorts, I do not require in any part of the apparatus a much higher
temperature than 1000 degrees, that being sufficient for generating the
gas in the retorts, and this temperature may, by means of my Invention,
be obtained with a much lower degree of heat in the furnace than is usually
employed, and consequently the brickwork or fire-bars of the furnace will
not be so powerfully acted upon, and will therefore last much longer than
is now the case. It will be evident, that al though I have described my
improvements as applied to furnaces in which coke is burned, the Invention
is equally applicable to those in which coal or tar is burned; but of course in
the latter case a somewhat different construction of fire-place must be
employed. For instance, the fire-bars must be removed, and instead thereof
the arrangement or construction of parts usually employed for burning this
combustible must be adapted; and it will be found advantageous and desirable
when tar is employed to make the furnace more capacious than that repre-
sented in the Drawings. I would here observe, that I am aware that hot air
has been heretofore used for increasing the combustion of fuel in fireplaces,
and also for converting carbonic oxide into carbonic acid; I do not therefore
claim these points as constituting any part of my Invention, except when
effected in the manner and for the purposes herein set forth and described.
But that which I consider to be the characteristic features of this part of my
improvements, as applied to the manufacture of coal gas, and wish to claim
under the herein-before in part recited Letters Patent, are the use of pipes
made either of iron, clay, or other suitable material, heated in flues or
chambers in which they become surrounded by the products of combustion in
their way from the oven to the chimney, and conducting heated atmospheric
air into the passages between the fuel and the retorts for the purpose above
shewn and described.
Another part of my Invention is an improvement or improvements, in the
manner of using chloride of calcium for the purification of coal gas. I do not
claim the use of that re-agent in a dry state, nor when it is in a fluid condition.
Both these ways are attended by inconvenience. In the one case fluids cause
objectionable pressure on the retorts, and in the other case dry chloride of
calcium dessicates the gas, and thereby causes it to deposit napthaline. Iavoid
both these evils by mixing the powdered chloride with sawdust or other
convenient and absorbent matter, and then sprinkling the mixture with water
until it becomes very damp or wet; or, which is still better, by causing a strong
solution of the chloride in water to be absorbed into dry sawdust or other

page_text: convenient matter, in such proportions as to confer upon the mass the form
of a wet and granulated powder.
:
I claim the use of chloride of calcium prepared in either of these ways for
the purification of coal gas, and I use it in the manner in common use for!
hydrate of lime.
I claim also the use of muriates and sulphates of manganese, iron, and.:
zinc, prepared by absorbing a strong solution of those salts respectively
into sawdust, as explained with respect to chloride of calcium ; but I do not
claim the use of either of the aforesaid metallic salts in a fluid state, or
in a state of mechanical division, and wetted, even though they be mixed with:
sawdust. In addition to the objectionable pressure caused by all fluids,
metallic solutions in particular obstruct the purifying apparatus by letting fall.
heavy precipitates, and the mere mechanical division of a metallic salt, such as
sulphate of iron, leaves in the centre of each fragment, however small it be, a
quantity of the re-agent on which the impurities in the gas can hardly be made.
to act. Chloride of calcium is both abundant and cheap; under certain
circumstances it may, however, be desirable to make it, for the purposes
of gas purifying, by decomposing muriate of manganese, iron, or zinc,bymeans
of lime, or of chalk when the latter will suffice. In such cases the oxides or
carbonates which result are useful for the said. purification, and need not be
removed. I do not claim either of these processes for making a mixture of..
chloride of calcium and a metallic oxide or carbonate, but I do claim the
application of mixtures so made to the purification of coal gas.
Another part of my Invention consists in the use of the carbonates of manga-
nese, iron, zinc, and lead for the purification of coal gas, for which purpose I
damp them, and dispose them,mixed or unmixed with sawdust or other matters,
in the course of the gas, as is practiced with the hydrate of lime, or I mix them
with the purifying matters which I have claimed as my Invention, or with other
purifying matters hitherto in use for a similar purpose, in a state of mechanical
division. To obtain these carbonates in an economical manner, I throw down
from ammoniacal or gas liquor obtained in making coal gas, and previously
distilled or not, the sulphur which it contains, and having drawn off the clear
liquid I next precipitate its carbonic acid, or instead of making two separate
precipitates I throw down a mixed sulphuret and carbonate of the precipitant
or precipitants. I prefer to precipitate by means of a muriate or sulphate of
manganese, iron, zinc, or lead.
I do not claim either of these ways of
cbtaining a metallic carbonate, but I claim the use of the carbonates above
named, however obtained, for the purification of coal gas.
Another part of my Invention consists in certain ways of treating the

page_text: ammoniacal liquor of gas works so as to obtain from it, and sulphate of lead, a
solution of sulphate of ammonia, and either. an oxide or a carbonate of lead
of sufficient purity so serve as or to be made into white lead. I proceed as
follows: The gas liquor is first distilled, either with lime or without addition.
In the former case the caustic ammonia, contaminated with hydrosulphuric
acid, is received in water; and in the latter case the carbonate and hydro-
sulphate of ammonia are received in water. In both cases the next step is to
remove the whole of the hydrosulphuric acid which the solution contains, and
which I prefer to do by starring in.enough carbonate of lead, taking care that
the clear liquid be afterward perfectly separated from the sediment. I next
stir in enough white sulphate: of lead to furnish to the ammonia its equivalent
of sulphuric acid. In the case of the caustic ammonia the lead will be found
at the bottom of the vessel asva white hydrated oxide, and in the case of the
carbonated ammonia a white carbonate of lead falls down; the solution in
either case containing sulphate of ammonia.
Another part of my Invention consists in increasing the purifying powers of
the aforesaid preparation. of chloride of calcium, or chloride of calcium and
metallic oxide, or chloride of calcium and metallic carbonate, and also of the
aforesaid metallic salts absorbed in solution into sawdust, by adding thereto
oxide of manganese, iron; zinc, or lead, obtained in a proper state from any
other economical source. The oxide which I prefer is one or other of the
oxides, of manganese prepared from the carbonate of that metal by a process
of which I claim the practical application. It is as follows:-I expose the
carbonate to a heat gradually increased to near redness, with access of air for
an hour or two, or until the 'carbonic acid be expelled and oxygen absorbed in
its place. If in this process the carbonate of manganese be contaminated
with sulphur, or if vegetable matter be present, and it ignite, or if the heat be
very great and too suddenly applied, or if the molecules of carbonate be
enveloped by soluble matter, then only a red or brown oxide results; but in
the absence of all those impediments so much oxygen combines with the
manganese as to convert it into the black or peroxide. I do not claim the
exclusive use of any metallic oxide for purifying coal gas; but what I do claim
is, the combination for that purpose of the oxides of manganese, iron, zinc, or
lead, or either of them, with the other purifying matters above recited, aud
whereby the gas may be perfectly purified from its ammonia and all its
hydrosulphuric acid, without requiring a succession of purifying vessels.
Another part of Invention consists in certain processes for making
carbonate of manganese. First, I mix together in solution muriate or
sulphate of manganese with an equivalent quantity of gas liquor, previously
my

page_text: distilled or not, but in either case carefully deprived by any known means of
its hydrosulphuric acid, and then, having withdrawn the supernatant liquid,
I thoroughly wash the precipitated carbonate with water. Secondly, I add
carbonate of soda to a solution of waste residue from the makers of chlorine,
which consists nearly of an equivalent of sulphate of soda and an equivalent
of sulphate of manganese, until the latter is decomposed. I then decant the
solution of two equivalents of sulphate of soda which results from the pre-
cipitated carbonate of manganese, and wash with water as before. The
solution of sulphate of soda also is a valuable product. Third, I boil car-
bonate of magnesia with an equivalent quantity of sulphate or muriate of
manganese in solution, and having decanted the solution of sulphate or
muriate of magnesia, I wash the precipitated carbonate of manganese..
Sometimes I replace the carbonate of magnésia by magnesian lime stone in
powder, and thus obtain the carbonate of manganese mixed with carbonate of
lime, which does not prevent its efficaceous application to the purification of
coal gas in the ways described, (that is to say,) either as a carbonate or con-
verted into an oxide.
Another part of my Invention consists in cert in economical processes for
applying preparations of lead and zinc to the purification of coal gas, and in
recovering them for repeated use. I will describe my manner of proceeding
with respect to lead, premising that the description will apply also to zinc:-
I procure a mixture of sulphate and oxide of lead in coarse powder; the exact
proportions will vary with the nature of the coals from which the gas has
been made, but they may be about two equivalents of the latter to one of the
former. I wet this mixture, and cause the gas to pass through it. After a time,
it ceases to purify the gas sufficiently, in consequence either of its sulphuric
acid being saturated with the ammonia, or the oxide no longer arresting the
hydrosulphuric and carbonic acids. A small quantity of acetic or nitric acid
may be added to the water with which the oxide is to be wetted. The used
matters, being removed from the purifying vessel, are dried, and exposed in a
furnace or on an iron plate for an hour or two to a low red heat, which
restores them again to the state of sulphate and oxide of lead, with the
volatilization of hydrosulphate of ammonia, which may be allowed to escape;
or if it be desired to save this ammonia, the heat at first should be applied to
the mixture in a retort, and the volatile matters conducted into water or some
acid or apparatus capable of condensing it, or the ammonia may be saved by
washing out the sulphate of ammonia from the used matters, and then exposing
the insoluble residuum to heat, as before stated, for its conversion into
sulphate and oxide of lead. For washing out the sulphate of ammonia I

page_text: sometimes use the gas liquors, either distilled or not, which have been already
converted into a solution of sulphate of ammonia by sulphate of lead, and
I repair the waste of sulphate and oxide of lead in the daily operation by
adding to the used mixture, before heating it, a part of the precipitated
sulphuret and carbonate of lead which results from the action of sulphate of
lead on the gas liquors.
In witness whereof, I, the said Richard Laming, have hereunto set my
hand and seal, this Fourth day of May, in the year of our Lord One
thousand eight hundred and forty-eight.
ANDERSON.
AND BE IT REMEMBERED, that on the same Fourth day of May, in
the year above mentioned, the aforesaid Richard Laming came before our
Lady the Queen in Her Chancery, and acknowledged the Specification
aforesaid, and all and every thing therein contained, in form above written.
And also the Specification aforesaid was stamped according to the tenor of
the Statute in that case made and provided.
Inrolled the same Fourth day of May, in the year above written.

page_text: In the Matter of Letters Patent granted to Richard Laming, late of
Clichy-la-Garenne, in the Republic of France, but now of Millwall,
Poplar, in the County of Middlesex, Manufacturing Chemist, for
his Invention of "CERTAIN IMPROVEMENTS IN MANUFACTURING AND
PURIFYING COAL GAS, AND IN TREATING A RESIDUAL PRODUCT OF SUCH
MANUFACTURE; ALSO IMPROVEMENTS IN PREPARING MATERIALS TO BE
USED IN THE PURIFICATION OF COAL GAS;" bearing date at West-
minster, the Fourth day of November, One thousand eight hundred
and forty-seven.
DISCLAIMER AND MEMORANDUM OF ALTERATIONS entered
by the said Richard Laming with the Clerk of the Patents of England,
pursuant to an Act passed in the fifth and sixth years of His late Majesty's
reign, intituled "An Act to amend the Law touching Letters Patent
for Inventions."
I, the said Richard Laming, do hereby declare that since the enrolment of
the Specification of my said Invention I have been able to carry out certain
parts of my Invention, and to prove their utility; but that from various causes
I have not been able to test the utility of other parts of my Invention; and
further, that from certain facts which have come to my knowledge, but chiefly
on account of proceedings which have been instituted by a rival manufacturer
Go set aside my said Patent by means of a writ of scire facias, I have reason
to doubt the novelty of certain matters set forth and claimed in my said
Specification. And I do hereby declare that from these causes, and also from
desire to simplify the proceedings indefending my Patent in a court of law,
I am desirous of disclaiming (under the provisions of the before-mentioned
Act) all those portions of my Specification which refer to the manufacture of
coal gas, to treating a residual product of such manufacture, and to the mode of
preparing materials to be used in the purification of coal gas, and also the use
of certain materials the application of which is claimed for the purification of
coal gas:
And I do hereby further declare that I am desirous of making such clerical
mendments and alterations as will render the Specification intelligible, after
such disclaimer and alterations have been allowed. And I do hereby further
declare, that for the purpose of making the Patent agree with the Specification

page_text: (after such disclaimer and alterations have been made as aforesaid), I propose
to strike out from the title all the words having reference to those heads of
the Invention which are disclaimed, leaving the title as follows:-" Certain
Improvements in Purifying Coal Gas." And I do hereby declare that I have
applied to and obtained the permission of Her Majesty's Attorney General to
enter such Disclaimer and Memorandum of Alterations as aforesaid. And I,
thesaid Richard Laming, do hereby declare, that, agreeably to such permission
of Her Majesty's Attorney General as a foresaid, I do hereby disclaim and omitin
my said Specification that part of the Invention which refers to the construction
offurnaces, the description of which commences with the words" The first part
of my Invention" and ends with the words "for the purpose above shewn and
described." In the paragraph commencing with the words "Another part of my
Invention is an improvement or improvements in the manner of using chloride
of calcium," I strike out the words "Another part of" and also the word "is;"
and after the word "is" I insert the words "consists firstly of." Further on
in my Specification, after the words "I avoid both these evils by," I omit
the following words, "mixing the powdered chloride with sawdust or other
convenient and absorbent matter, and then sprinkling the mixture with water
until it becomes very damp or wet, or, which is still better, by". Further on
occurs the word "proportions," which Falter into the singularnumber. In the
claims to this part of my Specification, after the words "the use of chloride of
calcium prepared," and before the words "for the purification of coal,
gas,"
I omit the words "in either of these ways," and in lieu thereof insert the
words "as above." Further on, in the claim following, I omit the word
manganese" and the words "and zinc." Further on, in the paragraph
commencing "chloride of calcium is both abundant," I omit the word
66 manganese "and the words "or zinc." In the description of that part of
my Invention relating to the use of carbonates of manganese, iron, zinc, and
lead, for the purification of coal gas, I strike out the words "manganese, zinc,
and lead," confining my Invention to the use of carbonate of iron. And I make
such further alterations as are necessary for the purpose of confining the
Invention to the singular instead of the plural number.
"
I disclaim and omit the whole of the description relating to the treating of
the ammoniacal liquor of gasworks, commencing with the words "Another
part of my Invention consists in certain ways of treating" and ending with the
words "the solution in either case containing sulphate of ammonia."
In that part of my Specification relating to increasing the purifying powers
of the preparation of chloride of calcium, &c., after the words "chloride of
calcium," and before the words "and also," I disclaim and omit the follow-

page_text: ing words, "or chloride of calcium and metallic oxide or chloride of calcium
and metallic carbonate." I also omit in the same paragraph the word
"manganese" and the words "zinc or lead," and between the words "any"
and economical" the word "other." I also omit the sentence beginning
"The exide which I prefer" down to and including the words "convert it
into the black or peroxide." Furtlier on I alter the word "oxides" into the
singular number, and omit the word "manganese," and also the words "zinc
or lead or either of them;" and further on I omit the words "recited and," and
substitute in their place the word "indicated."
I disclaim and omit those parts of iny Specification relating to the processes
for making carbonate of manganese, and applying preparations of lead and
zinc to the purification of coal gas, commercing with the words "Another part
of my Invention consists in certain processes for making carbonate of manga-
nese," down to and including the words "which results from the action of
sulphate of lead on the gas liquors."
And I disclaim and omit in the title of my said Patent the words "manu-
facturing and" and also the words "and in treating a residual product of such
manufacture, also improvements in preparing materials to be used in the
purification of coal gas," leaving the said title to read as follows: "Certain
improvements in purifying coal gas."
And I further declare that after the above-mentioned disclaimer and
alterations have been made my Specification will read as follows:-
My Invention consists, firstly, of an improvement or improvements in the
manner of using chloride of calcium for the purification of coal gas. I do not
claim the use of that re-agent in a dry state, nor when it is in a fluid condition.
Both these ways are attended by inconvenience. In the one case fluids cause
objectionable pressure on the retorts, and in the other case dry chloride of
calcium dessicates the gas, and thereby causes it to deposit napthaline.
avoid both these evils by causing a strong solution of the chloride in water to
be absorbed into dry sawdust or other convénient matter, in such proportion
as to confer upon the mass the form of a wet and granulated powder.
I
I claim the use of chloride of calcium, prepared as above, for the purification
of coal gas, and I use it in the manner in common use for hydrate of lime.
I claim also the use of muriates and sulphates of iron prepared by absorbing
a strong solution of those salts respectively with sawdust, as explained with
respect to chloride of calcium; but I do not claim the use of either of the
aforesaid metallic salts in a fluid state, or in a state of mechanical division,
and wetted, even though.they be mixed with sawdust In addition to the
objectionable pressure caused by all fluids, metallic solutions in particular

page_text: obstruct the purifying apparatus by letting fall heavy precipitates, and the
mere mechanical division of a metallic salt, such as sulphate of iron, leaves
in the centre of each fragment, however small it be, a quantity of the re-agent
on which the impurities in the gas can hardly be made to act.
Chloride of calcium is both abundant and cheap; under certain circum-
stances it may, however, be desirable to make it, for the purposes of gas
purifying, by decomposing muriate of iron by means of lime, or of chalk
when the latter will suffice. In such cases the oxides or carbonates which
result are useful for the said purification, and need not be removed. I do not
claim either of these processes for making a mixture of chloride of calcium
and a metallic oxide or carbonate; but I do claim the application of mixtures
so made to the purification of coal gas.
Another part of my Invention consists in the use of the carbonate of iron
for the purification of coal gas, for which purpose I damp it, and dispose it,
mixed or unmixed with sawdust or other matter, in the course of the gas, as
is practised with hydrate of lime, or I mix it with the purifying matters which
I have claimed as my Invention, or with other purifying matters hitherto in
use for a similar purpose in a state of mechanical division. To obtain this
carbonate in an economical manner, I throw down from ammoniacal or gas
liquor obtained in making coal gas, and previously distilled or not, the sulphur
which it contains, and having drawn off the clear liquid I next precipitate its
carbonic acid, or instead of making two separate precipitates I throw down a
mixed sulphuret and carbonate of the precipitant. I prefer to precipitate by
means of a muriate or sulphate of iron. I do not claim either of these ways
of obtaining a metallic carbonate; but I claim the use of the carbonate above
named, however obtained, for the purification of coal gas.
Another part of my Invention consists in increasing the purifying powers of
the aforesaid preparation of chloride of calcium, and also of the aforesaid
metallic salts, absorbed in solution into sawdust, by adding thereto oxide of
iron obtained in a proper state from any economical source. I do not claim
the exclusive use of any metallic oxide for purifying coal gas; but what I do
claim is the combination for that purpose of the oxide of iron with the other
purifying matters above indicated, whereby the gas may be perfectly purified
from its ammonia and all its hydrosulphuric acid, without requiring a succes-
sion of purifying vessels.
In witness whereof, I, the said Richard Laming, have hereunto set my
hand and seal, this Fourth day of June, in the year of our Lord
One thousand eight hundred and fifty-two.
(L.S.) RICHARD LAMING,

page_text: To the Clerk of the Patents of England.
This is to certify, that the above-named Richard Laming has applied to me
for leave to enter with you the above-written Disclaimer and Memorandum
of Alteration in the Title and Specification of a certain Invention for which
Letters Patent were duly granted to him under the Great Seal of Great
Britain, dated at Westminster, the 4th day of November, 1847, which was
enrolled on or before the Fourth day of May, 1848. And on considering the
said application, Idirected him to advertise his said Disclaimerand Alteration
in the London Gazette, in the Morning Herald, and the Times Newspapers.
And such advertisements have been duly made, namely, in the Gazette and
Morning Herald on the 18th, and in the Times Newspaper on the 19th day of
May last, and no valid objection having been made to the said application,
I have acordingly granted leave to the said Richard Laming to file his said
Disclaimer and Memorandum of Alteration, pursuant to the Statute passed
in the 5th & 6th years of the reign of His late Majesty King William the
Fourth, entitled "An Act to amend the Law touching Letters Patent for
Inventions."
AND BE IT REMEMBERED, that on the Fourth day of June, in the
year of our Lord 1852, the aforesaid Richard Laming came before our
said Lady the Queen in Her Chancery, and acknowledged the Disclaimer
aforesaid, and all and every thing therein contained and specified, in form
above written. And also the Disclaimer aforesaid was stamped according
to the tenor of the Statute made for that purpose.
Enrolled the Fifth day of June, in the year of our Lord One thousand