IMPROVEMENTS IN THE PURIFICATION OF WATER, AND, IN APPARATUS EMPLOYED. THEREIN
Year: 1862

page_text: LETTERS PATENT. to William Clark, of 53, Chancery Lane, in the
County of Middlesex,. Engineer and Patent Agent, for the Invention of
"IMPROVEMENTS IN THE PURIFICATION OF WATER, AND, IN APPARATUS
EMPLOYED. THEREIN."-A communication from abroad by Mr. Maurice
Laschi, of 29, Boulevart St. Martin, Paris.
Sealed the 3rd February 1863, and dated the 5th August 1862.
PROVISIONAL SPECIFICATION left by the said William Clark at the
⚫ Office of the Commissioners of Patents, with his Petition, on the 5th
.August 1862.
J, WILLIAM CLARK, of 53, Chancery Lane, in the County of Middlesex,.
Engineer and Patent Agent, do hereby declare the nature of the said Invention
for "IMPROVEMENTS IN THE PURIFICATION OF WATER, AND IN APPARATUS EMPLOYED
THEREIN," to be as follows:-
It is well known that calcareous water is not applicable for general and
domestic purposes on account of the earthy carbonates it contains. It is also
known that these carbonates which are insoluble in themselves, may be
rendered soluble by the aid of a certain quantity of carbonic acid termed
bi-saturating, which forms. them into soluble earthy. bi-carbonates. This

page_text: bi-saturating carbonic acid, which renders the earthy carbonates soluble,
possesses however so little affinity for the latter, that they may be more or
less readily and completely separated. This action may be effected by means
of many chemical agents, thus it is only necessary to add to the calcareous
water any chemical substance possessing greater affinity for bi-saturated
carbonated acid than the earthy carbonates, when the latter will be precipitated
on being deprived of the agent, by which they are held soluble in the water.
Among the substances suitable for purifying calcareous water, lime is one
which merits the greatest preference, and this for the following reasons:-
First, because lime on the one hand is an energetic base which readily absorbs
the carbonic acid, and thus allows of the earthy carbonates being precipitated,
on the other hand by converting itself into an insoluble carbonate it is itself
precipitated in turn without leaving any trace in the purified water; secondly,
the price of lime being at a minimum in comparison to that of other substances
it is incomparably cheaper compared with the results obtained; thirdly, the
lime may also be obtained every where and at all times in abundance. To
form an idea of the general advantages obtained by this new process it is
sufficient to mention that calcareous water deprived of its earthy carbonates
a, no longer produces incrustations in steam boilers; 'b, produces a saving
of from 60 to 80% on the consumption of soap necessary for. washing and
scouring;. c, produces a great economy in the combustible, especially for
cooking vegetables dry; d, is much better adapted for industrial and domestic
purposes. In order to find an easy, prompt, and certain means for determining
exactly the quantity of lime necessary for the purification of a given volume
of calcareous water, which would be equivalent to rendering it of practical
value, any substance which (although well known in principle) is attended
with great difficulties in its employment, could not be applied as a general
rule to the purification, on a large scale, of calcareous water. I obtain this
result by the employment of an instrument intended to determine exactly the
saturating power of any lime with respect to calcareous water, and vice versa,
the saturating power of calcareous water with regard to lime. These trials
are easily effected in the following manner:-1st, I take a glass bottle holding
about two and a half pints, and on which is a line marking the pints; 2ndly,
I take a glass bottle containing about 7 cubic inches having a line indicating
5 cubic inches; Brdly, I take a glass tube closed at one of its extremities
'of a capacity of about half a'cubic inch, and graduated in inches and fractions
of inches; '4thly, 'I take distilled water; 5thly, lime water; 6thly, two
glass tubes each of the capacity of about a cubic inch, one of which bears the
word "more," while the other has the word "less;" 7thly, I use a glass

page_text: mortar, a small funnel, and a balance to weigh exactly a weight of 150 grains.
(a) the bottle No. 1, is intended to receive a quart of water to be tried or
experimented on; (b) the bottle, No. 2, should contain milk of lime prepared as
herein-after described. I take 150 grains of the lime to be tested, taking care
that the quantity is composed of several small pieces so as to represent a
sample of the whole; these 150 grains being exactly weighed are introduced
in a glass mortar, and there washed with about half an inch of distilled water,
sometime after it is stirred and I add 4 cubic inches of distilled water,
agitating it for some time. In this manner I obtain a milk of lime, in which
each th of a cubic inch contains 14 grains of lime employed, the lime is then
placed in the bottle No. 2, which should be hermetically closed; (c) a glass
tube of the capacity of about half a cubic inch as above mentioned, is intended
to value in grains and tenths of grains the exact quantity of lime employed,
and which is necessary for the complete saturation of the carbonic acid
contained in the quart of water to be treated ; (d) the distilled water serves
for the preparation of the milk of lime as before mentioned; (e) lime water
which is contained in a bottle serving for the extra proof herein-after described,
(f) the two tubes indicating more and less may also serve for the extra
proof; (9) the mortar, is necessary for mixing the lime intended to produce
the milk of lime, and the cock for drawing off the milk of lime from the
mortar into the bottle for containing it. The scale is for weighing the
lime.
Form of operating the proof.-I first introduce the quart of water to be
tried into bottle No. 1; this done, I measure in the graduated tube c nearly
half a cubic inch of milk of lime from the mortar in the bottle (6), taking
care to shake it forcibly before measuring the lime water; after this is we!!
mixed in the tube I introduce two parts into the water above described, the
agitation is again effected several times, so that the lime shall be in contact
with all the parts of the water, after which I leave it to settle.
Counter proof. When the turbid liquid becomes limpid I pour into each of
the tubes, marked more and less, so as to fill them only about half way,
Immediately after this I add to the liquid of tube marked "more" from ten
to twenty drops of fresh calcareous water, similar to that employed, in mixing
the mixture, whilst in the tube marked "less" is put a sufficient quantity of
water of lime contained in bottle No. 5 to nearly fill it, and then agitate it
briskly. After some time the two tubes are compared to see which liquid is
turbid or has deposited white flakes; or, if on the contrary, each of them are
limpid without having any deposit. If, for example, a deposit appears in the
tube marked "more," it indicates that the quantity of lime added being. in

page_text: excess one part remains free, which has acted on the carbonic acid of the
'fresh water added, that being the case the test must be recommenced, which
may be limited to the introduction of a fresh quantity of water of the same
origin with a less quantity of milk of lime, commencing, for example, with
2th of a cubic inch instead of th.
I may here mention that this supposition is very improbable, as the case is
very rare in which a calcareous water to be purified requires less than th
of a cubic inch of lime, that is to say, less than 30 grains of lime, however
caustic it is. If, on the contrary, an agitation or deposit takes place in the
tube marked "less," this signifies that less lime has been introduced than is
necessary to saturate the carbonic acid of a quart of water under examination,
the carbonic acid, which by this reason is free, having reacted on the lime
water added. In this case some of the milk of lime should be poured in the
bottle No. 1 until the desired point of saturation is obtained, which is ascer-
tained by the fact that the purified water no longer acts either on the limpid
lime water or on the natural calcareous water, as above described. Lastly, if
the two tubes preserve the liquid perfectly limpid and without deposit, it
signifies that from the first the necessary quantity of the lime water has been
added for saturating the carbonic acid contained in the calcareous water to be
purified, when this point of saturation is roached the operation is terminated.
An exact note should be taken of the number of tenths and hundredths of
cubic inches of milk of lime employed, which is indicated by the scale on the
graduated tube No. 3. It is almost unnecessary to repeat that the said milk
of lime is composed in such manner that each th of a cubic inch contains
or is equal to one and a half grains, and each hundredth a hundredth part of
the above amount of lime employed.
Having thus developed, in all its details, this improved system of testing
exactly the quantity of lime necessary for saturating the carbonic acid in the
calcareous water, I will observe that besides the most perfect exactitude, this
process also prosents the greatest facility, requiring much longer time to
describe than execute.
Before finishing the description I think it necessary to give an example to
facilitate the practical application of this improved process. Supposing, for
example, that in order to saturate the carbonic aoid of a quart of this
calcareous water, I employ about the tenth of a cubic inch of the milk of
lime, therefore it follows that if a quart of this water requires this quantity,
'twenty-two gallons.would require 340 grains, and a cube of 39 inches requires
about 7 ounces. From the foregoing it is easily understood how by means of
'n very simple figure the proportion of lime and water of any volume can be

page_text: obtained, that is to say, by multiplying by 100 if it is for 20 gallons, and by
1000 if for a cube of 39 inches.
The chief features of the Invention are,―
1st, the improved method of ascertaining the proportion of lime necessary
for the purification of different calcareous waters by means of the instrument
before described, and which I term a hydro-calcimeter, by which alone this
improved purifying process can be rendered generally practicable..
2ndly, this improved instrument or hydro-calcimeter may also be used for
registering the amount of carbonic acid or carbonate, or for measuring the
caustic power of different kinds of lime.
3rdly, this improved system of purification may also be applied for the
extraction & utilization of precipitates, either natural or contained in other
matters, such as carbonic acid or sulphate of lime; or they may be reduced
and again rendered suitable for the purification of water or for other purposes.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said William Clark in the Great Seal Patent Office on the 4th
February 1863.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
CLARK, of 53, Chancery Lane, in the County of Middlesex, Engineer and
Patent Agent, send greeting..
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Fifth day of August, in the year of our Lord One
thousand eight hundred and sixty-two, in the twenty-sixth year of Her reign,
did, for Herself, Пer heirs and successors, give and grant unto me, the said
William Clark, Her special licence that I, the said William Clark, my exe-
cutors, administrators, and assigns, or such others as I, the said William Clark,
my executors, administrators, and assigns, should at any time agree with, and
no others, from time to time and at all times thereafter during the term
therein expressed, should and lawfully might make, use, exercise, and vend,
within the United Kingdom of Great Britain and Ireland, the Channel
Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN THE PURIFICATION
OF WATER, AND IN APPARATUS EMPLOYED THEREIN," a communication to me from
abroad by Mr. Maurice Laschi, of 29, Boulevart St. Martin, Paris, upon the
condition (amongst others) that I, the said William Clark, my executors or
administrators, by an instrument in writing under my, or their, or one of their
bands and seals, should particularly describe and ascertain the nature of the

page_text: said Invention, and in what manner the same was to be performed, and
cause the same to be filed in the Great Seal Patent Office within six calendar
months next and immediately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said William Clark, do hereby declare the
nature of my said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement (that is to say)
It is well known that calcareous water is not applicable for general and
domestic purposes on account of the earthy carbonates it contains. It is also
known that these carbonates, which are insoluble in themselves, may be
rendered soluble by the aid of a certain quantity of carbonic acid, termed
bi-saturating, which forms them into soluble earthy bi-carbonates. This
bi-saturating carbonic acid, which renders the earthy carbonates soluble;
possesses, however, so little affinity for the latter that they may be more or less
readily and completely separated. This action may be effected by means of
many chemical agents; thus, it is only necessary to add to the calcareous water
any chemical substance possessing greater affinity for bi-saturating carbonic
acid than the earthy carbonates, when the latter will be precipitated on being
deprived of the agent by which they are held soluble in the water. Among
the substances suitable for purifying calcareous water lime is the one which
merits the greatest preference, and this for the three following reasons:-
First, because lime, on the one-hand, is an energetic base which readily absorbs
the carbonic acid and thus allows of the earthy carbonates being precipitated;
on the other hand, by converting itself into an insoluble carbonate it is preci-
pitated in its turn without leaving any trace in the purified water. Secondly,
the price of lime being at a minimum in comparison to that of other
substances it is incomparably cheaper compared with the results obtained.
Thirdly, the lime may also be obtained everywhere and at all times in
abundance. To form an idea of the general advantages obtained by this new
process it is sufficient to mention that calcareous water deprived of its earthy
carbonates a, no longer produce incrustations in steam boilers; b, produces a
saving of from 60 to 80 per cent. on the consumption of soap necessary for
washing & scouring; c, produces a great economy in the combustible,
especially for cooking vegetables dry; d, is much better adopted for industrial
and domestic purposes.
In order to find an easy, prompt, and certain means of determining exactly
the quantity of lime necessary for the purification of a given volume of
calcareous water, which would be equivalent to rendering it of practical value;
any substance which (although well known in principle) is attended with

page_text: great difficulties in its employment, could not be applied as a general rule to
the purification on a large scale of calcareous water. I obtain this result by.
the employment of an instrument intended to determine exactly the saturating
power of any lime with respect to calcareous water, and' vice versa, the satu-
rating power of calcareous water with regard to lime. These trials are easily
effected in the following manner:-1st, I take a glass bottle holding about.
two and a half pints, and on which is a line marking the pints; 2ndly, I take
a glass bottle containing about 7 and a half cubic inches, having a line indi-
cating five cubic inches; 3rdly, I use a glass tube, closed at one end, of a
capacity of about half a cubic inch, and graduated in inches and fractions of
inches; 4thly, I take distilled water; 5thly, lime water; 6thly, two glass.
tubes, each of the capacity of about one cubic inch, one of which has the word:
"more," while the other has the word "less;" 7thly, I use a glass mortar, a
small funnel, and a balance to weigh exactly a weight of 150 grains. a, bottle-
No. 1, is intended to receive a quart of water to be tried or experimented on;
b, the bottle No. 2, should contain milk of lime, prepared as herein-after
described. I take 150 grains of the lime to be tested, taking care that the
quantity is composed of several small pieces, so as to represent a sample of the
whole; these 150 grains being exactly weighed are introduced in a glass
mortar and there washed with about half a cubic inch of distilled water, some
time after it is stirred, and I add four and a half cubic inches of distilled
water, agitating it for some time. In this manner I obtain a milk of lime in
which each oth of a cubic inch contains 1 grains of lime employed; the'
lime is then placed in the bottle No. 2, which should be hermetically closed.
c, a glass tube of the capacity of about half a cubic inch, as above mentioned,
is intended to value in grains and tenths of grains the exact quantity of lime
employed and which is necessary for the complete saturation of the carbonic
acid contained in a quart of water to be treated; (d), the distilled water serves'
for the preparation of the milk of lime, as before mentioned; (e), lime water,'
which is contained in a bottle, serving for the extra proof herein-after described;
(f), the two tubes indicating "more" and "less" should also serve for the
extra proof; (9), the mortar is necessary for mixing the lime intended to
produce, the milk of lime; the cock for drawing off the milk of lime from the
materials into the bottle for containing it; the scale for weighing the lime.
i
Form of operating the proof.-I first introduce the water to be tried into
bottle No. 1. This done, I measure in the graduated tube, letter c, nearly half
a cubic inch of milk of lime from the mortar in the bottle b, taking care to
shake it forcibly before measuring. To this lime water, which is well mixed
in the tube, I introduce two parts into the water above described, the agitation

page_text: is again effected several times, so that the lime shall be in contact with all the
parts of the water, after which I leave it to settle.
Counterproof. When the turbid liquid becomes limpid I pour it into each
of the tubes marked "more" and "less" so as to fill them only to about half
way, immediately after this I add to the liquid of tube marked "more" from
ten to twenty drops of the fresh calcareous water, similar to that employed in
mixing the mixture, whilst in the tube marked "less" is put a sufficient
quantity of water of lime contained in bottle No. 5 to nearly fill it, and then
agitate it briskly. After some time the two tubes are compared to see which
liquid is turbid or has deposited white flakes, or if, on the contrary, each of
them aro limpid without having any deposit. If, for example, a deposit
appears in tube marked "more" it indicates the quantity of lime added being
in excess. One part remains free which has acted on the carbonic acid of the
fresh water added, that being the case the test must be recommenced, which
may be limited to the introduction into a fresh quantity of water of the same
origin a less quantity of milk of lime, commencing, for example, with th of
a cubic inch instead of th.. I may here mention that this supposition is
very improbable, as the case is very rare in which a calcareous water to be
purified requires less than th of a cubic inch of lime, that is to say, less than
30 grains of lime, however caustic it is. If, on the contrary, an agitation or
deposit takes place in the tube marked "less," which signifies that less lime
has been introduced than is necessary to saturate the carbonic acid of a quart
of water, in examining the carbonic acid, which by this reason is free, having
reacted on the lime of lime water added. In this case some of the milk of lime
should be poured in the bottle No. 1 until the desired point of saturation is
attained, by which is ascertained the fact that the purified water no longer
acts either on the limpid lime water or the natural calcareous water as above
described. Lastly, if the two tubes preserve the liquid perfectly limpid and
without deposits it signifies that from the first just the necessary quantity of
water has been added to the lime for saturating the carbonic acid contained in
the calcareous water to be purified. When this point of saturation is reached
the operation is terminated. An exact note should be taken of the number
of tenths and hundredths of cubic inches of milk of lime employed which is
indicated by the scale on the graduated tube No. 3.
It is almost unnecessary
to repeat that the said milk of limé is composed in such manner that each th
of a cubic inch contains, or is equal to 1½ grains, and each hundredth a
hundredth part of the above amount of lime employed.
Having thus developed in all its details this improved system necessary for
saturating the carbonic acid in the calcareous water, and of testing exactly the

page_text: quantity of lime, I will observe that besides the most perfect exactitude this
process also presents the greatest facility, requiring much longer time to describe
than to execute.
Before finishing the description I think it necessary to give an example to
facilitate the practical application of this improved process. Supposing for
example that in order to saturate exactly the carbonic acid of a quart of this
calcareous water I employ about a tenth of a cubic inch of the milk of lime,
therefore it follows that if a quart of this water requires this quantity; 22 gallons
would require 340 grains, and a cube of 39 inches require about 7 ounces. From
the foregoing it is easily understood how by means of a very simple figure, the
proportion of lime and water of any volume can be obtained, that is to say, by
multiplying by 100 if it is for 20 gallons, and by 1000 if for a cube of 39
inches. It will be unnecessary to repeat that if the process is to be applied
on a large scale it is only necessary to weigh a quantity of lime in proportion
to the volume of water to be purified. This lime when reduced to milk of
lime, as usual, should be mixed with the water by any ordinary mechanical
means. A reservoir from which the precipitates may be extracted by means
of a valve is preferable while the mixture will be effected with more facility
& compactness if the milk of limė be introduced into the reservoir in the
same proportion and time as the water to be purified enters, this may be
easily effected as the milk of lime may be passed out of one orifice in the same
proportion as the water that enters said reservoir. The advantage of this
arrangement will be apparent as this instrument renders practicable the
rational application of a process hitherto unattainable. There is yet a further
advantage to be derived from this Invention, thus it is well known that quick-
lime may not be preserved in a mass in that state, as by readily absorbing
water and carbonic acid from the air it loses its caustic properties, and
ultimately becomes converted into hydro-carbonated lime, and for this reason
immediately on its extraction from the calcining furnaces it is immediately
sprinkled with water and converted into a paste which is termed slaked
lime. Lime thus slaked consists of bydrate of lime with an excess of
water varying in quantity to an indefinite extent. In this state it may be
preserved for a length of time without losing its causticity. It will thus be
readily understood that this Invention permits of the preservation and use
of lime necessary for the purification of the water although transformed into
slaked lime while without the improved instrument of this Invention the appli-
cation of such slaked lime for purifying water becomes an impossibility from
the difficulty of finding the exact relation between the weight of the former
and that of the caustic lime.

page_text: .
But although the question of the rational application of lime for the purifi-
cation of small quantities of water limited to daily requirements presents no
practical difficulty, it is otherwise when the question is considered from a
more extensive point of view, that is to say, when applying the lime to large
quantities of water, as a town supply, for instance, where rivers, so to speak,
of water are required daily, difficulties then spring up from the immensity of
the operation itself, for overcoming which it may well be supposed that the
foregoing processes will be inadequate and where oftener the task will have to
be given up entirely.
These difficulties consist, 1st, as regards limited applications, the cost of the
lime necessary for dialy use may be entirely overlooked, while when acting, on
the contrary, on immense masses of water the multiplication of this expense
alone represents a very high amount; 2ndly, it is also more difficult than would
be supposed to obtain in any country at one place the quantity of lime necessary
for treating such large quantities of water; seriously speaking, these are the two
principal difficulties to overcome, which from their character paralyze all attempts
to effect the grand purpose of obtaining pure water for the indiscriminate use
of towns. I have seriously considered the means for solving these two latter
difficulties, which I believe I have effected as follows:-When treating a given
volume of calcareous water by a given and ascertained weight of lime, as before
described, a precipitate consisting of earthy carbonates is collected, which
carbonates, when calcined, will furnish quicklime, the weight of which represents
not only that of the lime employed, but also of the lime in the carbonates
previously existing in the water itself. Thus more is received than is given.
The surplus lime amounts to almost double although ordinarily it varies between
40 and 80% of the lime used. This then in a few words is the principle
on which may be based a new manufacture of lime extracted from calcareous
water which may serve for purifying water anew or for any other applications
of which this substance is susceptible. From the foregoing which I have
proved by experiment follows the application of the herein described process
on a large scale based upon the following facts:-
1st, that by reducing the carbonate of lime which is precipitated, I obtain
the lime on the spot in proportion to requirements without being obliged to
obtain it from a distance more or less great.
2ndly, the expense of the lime, which was the least favorable feature of the
hypothesis, entirely disappears, hence large masses of water may be purified
.without expense as regards a purifying agent and even with a profit in many
instances.

page_text: Having described the nature of this Invention and the manner of describing
the same, I declare that what I claim as the Invention to be protected by the
herein-before in part recited Letters Patent is,-
First, the improved method of ascertaining the proportions of lime necessary
for the purification of different calcareous waters, by means of the instrument
herein-before described, and which I term a "hydro-calcimeter," by which
alone this improved purifying process can be rendered generally practicable.
Secondly, I claim the application of this improved instrument or hydro-
calcimeter for registering the amount of carbonic acid or carbonates, or for
measuring the caustic power of different kinds of lime.
Thirdly, I claim the application of this improved system of purification for
the extraction and utilization of precipitate either natural or contained in other
matters, such as carbonic acid or sulphate of lime, or they may be reduced to
lime and again rendered suitable for the purification of water, or for other
purposes, in the manner and as herein-before described.
In witness whereof, I, the said William Clark, have hereunto set my
hand and seal, this Fourth day of February, in the year of our
Lord One thousand eight hundred and sixty-three.
0 Witness,
W. G. E. SWINNOCK,
53, Chancery Lane.
London.
W. CLARK. (L.B.)