IMPROVED APPARATUS FOR FEEDING STEAM BOILERS WITH WATER, AND FOR PURIFYING SUCH WATER FROM EARTHY MATTERS
Year: 1878

page_text: LETTERS PATENT to Alfred Dervaux, of Brussels, in the Kingdom of Belgium,
"
Engineer, for the Invention of IMPROVED APPARATUS FOR FEEDING STEAM
BOILERS WITH WATER, AND FOR PURIFYING SUCH WATER FROM EARTHY
MATTERS."
Sealed the 24th September 1878, and dated the 4th April 1878.
PROVISIONAL SPECIFICATION left by the said Alfred Dervaux at the Office
of the Commissioners of Patents on the 4th April 1878.
IM-
ALFRED DERVAUX, of Brussels, in the Kingdom of Belgium, Engineer.
PROVED APPARATUS FOR FEEDING STEAM BOILERS WITH WATER, AND FOR PURIFYING
SUCH WATER FROM EARTHY MATTERS."
23
"The object of this Invention is to afford a continuous and regulated supply of
pure water to steam boilers in such a manner that the water therein may be main-
tained at an uniform level, or nearly so.
In combination with the apparatus for supplying the water from the reservoir
to the boiler there is an apparatus (through which the feed water passes on its way
to the boiler) whereby any calcareous or earthy matters contained in the water may
be removed therefrom before the water is allowed to pass into the boiler.
The feed water apparatus consists of a conical socket, in which works a hollow
conical plug divided into two compartments A and B, each of which comprises a
certain number of cavities or recesses, four for instance. The spindle of this hollow
conical plug carries at its upper part a worm wheel, into which gears a worm,
whereby a continuous rotary motion is imparted to the hollow conical plug. There
is also at the extreme end of the spindle of the hollow conical plug another worm
wheel and gearing, whereby it may be turned round horizontally in its socket, and
adjusted therein with great accuracy so that the relative position of the openings
in the plug and its socket may be regulated as may be required.
The feed water from the reservoir runs by gravitation through suitable pipes
into receiving chambers adapted to the upper part of the fixed conical socket, and

page_text: passes through openings made therein into spaces or recesses made in the upper
compartiment A of the rotating hollow conical plug, and by the rotation of this
latter the spaces of the upper compartment A are brought into communication with
the open ends of two pendant tubes, the lower ends of which are carried down to
nearly the bottom of a condensing chamber or chainbers which are adapted to and
communicate with the lower compartment B of the fixed conical socket. The water
from the upper compartment A of the conical hollow plug thus passes down the
pendant tubes into the lower or condensing chainber of the fixed conical socket, and
from thenco to the lower compartment B of the rotary conical hollow plug. On the
hollow conical plug continuing to rotate the cavities or recesses of the lower com-
partment B will be brought opposite to the ends of pipes adapted to openings made
in the fixed conical socket.
The feed water may be conducted by these pipes direct to the boiler to be
supplied; or if it requires to be purified it may be conducted to a close chamber,
which constitutes the purifier, and in which the earthy and solid matters are
eliminated from the water, after which it is passed into the boiler.
There may be two of these feed pipes, one of which is carried to the normal level
of the water in the boiler and the other to the maximum level. The open end of
this former is enclosed in a short cylinder, which has openings at its upper part to
admit steam to the interior. From the bottom of this cylinder is suspended a pipe,
which extends down to nearly the bottom of the boiler, and of course conducts the
feed water down to that part.
The effect of this arrangement of parts is that immediately the level of the
water in the boiler sinks below the normal point, the end of the feed water pipe
in the small cylinder becomes uncovered, and steam will rush up the feed pipe into
the upper compartiment A of the conical plug, and will press on the water therein
and force it down the pendant pipes into the condensing chambers, and from thence
into the lower compartment B of the rotary plug, from whence it will pass as
already explained along the second feed water pipe into the boiler, and will again
close the open end of the other feed pipe. Should the level of the water by any
negligence or accident sink below the minimum level, and thus expose the end of
the other feed pipe, steam would rush up the latter and pass into the hollow plug,
and would thereby prevent any water from coming down and causing an explosion.
The escape of the steam from the boiler through the feed pipe into the fced water
apparatus will hent the water nearly to the boiling point, and will drive off the
carbonic acid held in solution in the water. The earthy matters will thus become
precipitated, and the water with the earthy matters will pass into the intermediato
vessel of the purifying apparatus in which the solid matter will be deposited, and
the purified water will then pass into the boiler.
If this improved feed water apparatus be required to supply water to several
boilers at once, this may be done by increasing the number of the feed pipes that
are adapted to the conical socket. These feed pipes, together with their passages,
communicate only with the boiler to which they belong, and have no connection
whatever with each other, although all the boilers may be in use together and all
fed with water through the same apparatus.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Alfred Dervaux in the Great Seal Patent Office on the 4th October
1878.
"
ALFRED DERVAUX, of Brussels, in the Kingdom of Belgium, Engineer. IM-
PROVED APPARATUS FOR FEEDING STEAM BOILERS WITH WATER, AND FOR PURIFYING
SUCH WATER FROM EARTHY MATTERS."
The improved apparatus which forms the subject of the present Invention
consists of a conical shell, into which is fitted a hollow plug divided into two
compartments A and B containing each a certain number of cavities, four for
instance.
A continuous rotary motion is imparted to the conical plug by means of a wheel
and worm, so that water from a cistern filled for this purposo will flow along tubes
into the water chambers and will cuter into the cavities of the upper compart-
ment A, and pass through the two descending pipes into two condensing chambers.
The cavities of the lower compartiment B will admit the water thus poured into
the condensing chambers, and will conduct it into the passages or openings, from
whence it will pass into the boiler.
In the accompanying Drawing,
Fig. Lis a vertical section of the apparatus taken in the line a, b, of Fig. 3.
Fig. 2 is another vertical section of the apparatus, but taken in the line c, d, of
Fig. 3, which is a horizontal section taken in the line c, f, of Figures 1 and 2.
Fig. 4 is another horizontal section taken in the line g, h, of Figures 1 and 2.
Fig. 5 is a plan or top view of the apparatus.
Fig. 6 is a vertical section of the conical shell and hollow plug constructed and
arranged to feed four boilers at once or simultaneously.
Fig. 7 is a sectional view representing the mode of adapting the improved feeding
apparatus to a boiler in conjunction with an apparatus for purifying the feed water
from earthy matters.
When the apparatus is intended for feeding only one boiler with water, as shown
at Fig. 7, the openings V and V₁ must be united and brought to communicate with
the boiler by the steam pipe V (as shewn in Fig. 7), whilst the openings S and S¹
must be connected together and then made to communicate with the vessel D by
the feeding pipe S. This vessel D (the use of which will be explained in the
course of this Specification) communicates with the water space of the boiler G by
a pipe S, which is practically a continuation of the pipe S¹. As the feeder is placed
in a position above the level of the water contained in the boiler, and as its con-
struction is such that the steam upon entering the openings V, V₁, acts on the top
of the water conducted by these openings into the cavities of the compartment B,
this water is forced to flow along the openinga S, S', into the vessel D, and from
thence into the boiler G, leaving the space which it occupied in the cavities of the
compartment B to be filled with an equal bulk of steam.
The steam pipe V¹ descends within the boiler G to the level at which the water
should stand, consequently water instead of steam will rush into this pipe as soon
as the water is raised to the proper water line, and as from this instant a sub-
stitution of steam for the water contained in the cavities of the compartment B is
no longer possible, the feeding is stopped until the level of the water in the boiler
has fallen a little.
The advantages derived from this arrangement are that the feeder is always
maintaining within the boiler a normal water level, which can never be exceeded,
and moreover an excessive supply of water is rendered utterly impossible by the
application of the apparatus. On the other hand the feeding pipe Se descends
within the boiler G, not to the bottom of it, as has been the case up to the present
time, but only to that lowest level, below which a continued feeding might become
dangerous. It follows from this that whenever (from want of care and attention)

page_text: the level of the water should have fallen below the lowest point at which it should
be admitted, steam will rush into the feed pipe and will prevent the water from
entering into the boiler, which latter process, as it may be easily understood from
what has gone before, can only take place in consequence of the difference existing
between the level of the apparatus and that of the water in the boiler, hence a
deficient as well as an excessive supply will be avoided by the use of the improved
feeding apparatus.
If the water to be used for feeding the boiler is very pure, the vessel D may
be dispensed with, and the feeding apparatus may be brought into direct commu-
nication with the boiler by the pipe S, but should the water (as is generally the
case) contain solutions of salts of lime, the utility and application of the vessel D as
a purifier will be evident, as will be explained further on.
When two boilers are to be supplied with water by one single apparatus, the
steam pipe of one of these boilers must be connected with the opening V and the
feed pipe of the same boiler with the opening S, the steam and water pipes of the
other boiler must be connected in a similar manner, that is, the steam pipe should be
connected with the opening V' and the water pipe with the opening St. The two
boilers will now be fed separately but simultaneously, and however great the dif
forence existing between their levels may be, the action will be the same as in the
case of only one boiler being supplied. Thus any number of boilers may be fed
simultaneously by one single apparatus without requiring the use of floats or regu-
lators of any description nor necessitating any regard to be taken as to the
difference in their water levels.
In the latter case, however, the lower compartment B and the corresponding
part of the shell of the apparatus must be modified in the manner shown in
Fig. 6.
With respect to an arrangement for the sinultaneous feeding of, say, four boilers,
which are not shewn in the Drawings, but may be called No. 1, No. 2, No. 3, and
No. 4, the pipe V' receives the steam from the boiler No. 1, whilst the pipe S¹ serves
to conduct the water to the same boiler, the pipes V³, S³, V³, S³, V, S, are arranged
in a similar manner for the feeding of the boilers No. 2, No. 3, and No. 4, re-
spectively.
The cavities b, b, b, b, of the compartment B, will, one after another, be brought
before the openings V₁, S¹, V2, S3, and will serve to feed the boilers No. 1 and No. 2,
whilst the cavities b¹, b¹, b¹, b', are intended for the feeding of the boilers No. 3
and No. 4. When only three boilers shall be supplied with water, two and two
of the openings V₁, V, and S1, S2, or of the openings V, V, and S³, S, must be
connected together, and another series of cavities with corresponding openings
adapted to pipes for the admission and escape of steam and water respectively, is
to be added to the compartment B in case six steam generators require to be supplied
and so forth.
It is obvious that the steam and feed pipes of the different boilers must be kept
apart from each other, that is to say, they must not have any communication with
each other throughout their entire length, consequently each boiler must be provided
with a vessel D whenever the feed water contains calcareous substances or other
impurities.
When the emptied cavities of the compartment B are brought opposite to the
chambers C, C, in order to be filled again, the steain which they contain will be
condensed by the water in the interior of these chambers, and any previous escape
of steam (owing to an inevitable deficiency of the plug, which may not always fit
the shell with minute precision), will be directed from the openings V, VI, S, S', to
the chambers C, C¹.
Therefore a continual disengagement of steam is produced within the lower part
or water space of the condensing chambers C, C', whilst at the same time com-
paratively cold water coming from the cistern will be incessantly flowing into them
through the upper compartment A.
If the water were allowed to run immediately into the upper part or steam room

page_text: of the condensing chambers C, C', a sudden condensation of the steam contained in
them, and subsequently a violent and continual ebullition of the water contained in
the condensers would be the consequence.
As the water would become incapable of rapidly condensing the steam carried
along by and issuing from the cavities of the compartment B, the latter would be
prevented from getting completely filled with water, and the efficiency of the boiler
feeder would thus be lessened to a great degree. The water issuing from the cistern
is therefore caused to run directly into the water space of the condensers C, C',
through the descending tubes P, P¹, which may be replaced by openings or passages
cast with the shell in one piece, if this should prove to be more advantageous. By this
contrivance the violence of ebullition of the water contained in the condensing chambers
is (if not entirely prevented yet) considerably diminished as the water is only subject
to something of a quiet boiling which can hardly interfere with the process of filling
the cavities of the compartiment B. Besides, the cavities of the compartment B are
made much larger in size than those of the compartment A, for instance, twice as
large, so that the cavities of the compartment B, although absorbing all the water
issuing from the cistern through the upper compartment A, while said cavities are
passing the receivers C, C¹, will be only half filled, thus even a violent ebullition of
the water in the condensers can have no longer any considerable influence upon the
water supply.
In order to facilitate the application of a compartment B, the cavities of which
are made much larger than those of the compartment A, and also to fulfil certain
conditions of equilibrium and precision which shall be explained further on, the
cone of the apparatus is inverted, so that the largest diameter is at the lower end,
and the smaller diameter at the upper end of the plug and shell, although this
arrangement presents some other inconveniences with regard to construction,
mounting, and attendance.
One of the most important conditions to prevent a violent obullition is that an
equilibrium of temperature must always exist between the steam and water con-
tained respectively in the steam and water spaces of the condensing chambers
C, C; and in order to obtain this without great difficulty these chambers are made
of considerable capacity, otherwise simple channels cast with and going through
the thickness of the shell, and connecting the compartments A and B with each
other, would be sufficient.
Another equally important reason for not connecting together the two compart-
ments A and B simply by plain channels, but by means of comparatively capacious
chambers will be explained hereafter, when describing the application of the
apparatus for the purification of water.
As the difficulty of preventing an ebullition of the water contained in the con-
densers C, C, will increase in proportion as the water flowing from the cistern is
colder, it will be convenient to furnish the apparatus with an accessory valve F (see
Fig. 1), which is intended to maintain a direct communication between the con-
densers and the atmospheric air, or with the water cistern, as long as the pressure
in the condensers is inferior to that of the external air; this valve may be substi-
tuted for the tubes P, P', in case of feeding with cold water.
By this device an ebullition will be completely prevented as long as the
water in the condensers has not reached a temperature of one hundred degrees,
because the water of the condensers would be subject to a pressure superior to that
corresponding with its temperature.
The shell m, n, o, p, is exposed to the effects of expansion and contraction
resulting from the different degrees of temperature existing between the various
parts of the feeder when in use. Thus the lower part of the shell will be expanded
on the side of the steam and water pipes, and will be relatively contracted on the
side of the condensers C, C', while, on the contrary, the upper part will be com-
paratively expanded on the side of the condensers, and contracted on the side of
the water chambers R, R¹.
To avoid as much as possible the injurious effect of these strains, which might

page_text: considerably warp or distort the shell, and cause a considerable escape of steain
from the openings V, VI, IS, S', into the condensers, and from thence into the
chambers R, R', the condensers C, C¹, and chambers R, R¹, are fastened to the
corresponding apertures of the shell by means of flanges and bolts, for which
purpose they are now constructed separately instead of being cast with the shell in
one single piece.
The vessels C, C', and R, R', thus insulated from the shell m, n, o, p, may now
contract and expand without affecting the latter. Morcover, thin boards c, x, x, x,
Y., Y, y, consisting of wood, caoutchouc, or other suitable material which is a bad
conductor of heat, are secured to those walls of the orifices of the shell which
communicate with the water space of the condensers, and to those to which the
chambers R, R, are fastened with the intention of protecting the orifices of the
shell from direct contact with the water of the condensers, and with that coming
from the cistern, and thus to prevent a warping of the shell. As to the plug itself,
to which a continuous rotary motion is to be imparted, it will when once put in
operation be subjected to an uniform temperature, and will expand accordingly.
A permanent communication between the openings V, VI, for the admission of
steam, and those marked S, S', for the eduction of water, is obtained by means of
the two channels Z, Z, which are cast with the shell, but in lieu of which the tubes
may be used for connecting the steam and water pipes. By this means the feeding
powers of the apparatus are notably increased, and a great regularity in the water
supply is obtained; indeed, the supply of water may be considered as taking place
continuously, diminishing only in proportion as the actual level of the water in the
boiler is more and more approaching the proper water line. The supply of water
then becomes exactly in accordance with the consumption of the boiler.
Another great advantage of this permanent communication between the openings
of the steam and feed pipes will be referred to, when speaking of the purification
of the feed water by means of the apparatus.
Instead of the channels Z, Z, a tube Z may be used, which would have the same
effect.
Every time the steam conies too suddenly in contact with the water contained
in the cavities of the compartanent B, and enters the passages or openings V, VI,
S, S¹, a jerk is caused within the feed pipe. This may be prevented by constructing
the orifices, which admit the steam into the interior of the shell in the form shewn
in Figs. 1 and 2, or by giving them any other convenient shape by which a slow
and progressive admission of steam above the water contained in the cavities may
be effected.
The same end may be attained by so shaping the orifices for the admission of
steam that they will have throughout their entire length the full diameter of the
openings V, VI, and by providing the cavities of the compartment B with
openings of a section similar to that of the orifices of the shell shewn in Figs. 1
and 2.
The feed openings S, S', are slightly inclined to the axis of the shell (as shown in
the Drawings) with a view to facilitate the complete emptying of the cavities of
the compartment B.
The steam openings are inclined in the same manner, so that, 1stly, the water,
which had been carried along by the current of the steam which issues from the
boiler, may run off more readily through the channels Z, Z1; and, 2ndly, that
the steam, instead of passing through the water contained in the cavities, will enter
above it into the cavities of the compartment B, and will heat only the surface of
the water before the latter is discharged into the boiler.
By increasing the speed of the apparatus, which may be done without incon-
venience, the water in the cavities of the compartment B will be still less heated,
and subsequently the formation of calcareous sediments will be diminished.
The tube T forms an exit for the air and carbonic acid, which are constantly dis-
engaged from the water in the condenser C, C', in consequence of its ebullition; it
also forms an exit for the steam which might accidentally or during the time the

page_text: machine is stopped accumulate in the water chambers R, R'. The pipe T thereby
serves to maintain a communication between it and the cistern, and must terminate
in the water contained in the latter, and have a continual fall towards the
apparatus.
As it will be very difficult to render the cock perfectly steam-tight, a groove M
made between the two compartiments A and B, either on the plug, as shewn, or in
the thickness of the shell, connects the two condensers, and receives and discharges
into the condensers the leakage which might be likely to occur from the cavities of
the compartiment B into those of the compartment A.
Another groove N, also made either in the plug or in the thickness of the shell,
forms a passage between the two chambers R, R¹, and receives and discharges into
these chambers the steam which might tend to escape from the condensers C, C',
into the atmosphere, thus opening for it an exit to the feeding cistern; this arrange-
ment permits of entirely dispensing with any stuffing boxes or packing around the
plug, as the interior of the chambers R, R', which is only subject to the pressure of
the water of the cistern, is also sufficiently cut off from the external atmosphere by
the close contact of the upper part of the plug with the inner surface of the shell;
however, should a slight escape of steam take place, this steam will be taken up and
be finally emitted into the open air through the small waste pipe t.
By reference to the Figures 1, 2, 3, and 4 of the Drawings it will be easily under-
stood that the different horizontal pressures sustained by the plug are in perfect
equilibrium. As to the vertical pressures, they will be in a constant downward
direction, in consequence of the improved apparatus having its coue inverted, that
is to say, having the largest diameter not at its upper but at its lower end. The
pressure is still farther increased by the plug's own weight, which will always tend
to draw it from its seat, the plug being entirely supported by the box screw K,
against which a ring H bears, as shewn in Fig. 1. The advantages of this constant
direction of the vertical pressures resulting from the inverted position of the cone
of the apparatus are, that without any inconvenience some play may exist among
the various parts of the apparatus, and will serve to regulate the position of the
plug in the shell (as, for instance, the screw of the box K), and that very great
precision may be easily obtained without having to fear any difficulties either in
mounting or construction.
A constant pressure in a downward or upward direction may however be given
even should the cone of the apparatus have its largest diameter at the upper end;
this will be effected by means of a spring, or by a direct weight, or by a levor and a
spring or counterweight acting vertically on the plug, and forcing it either to ascend
or to descend within the shell.
All these possible modifications may be advantageously employed provided the
principle of maintaining the same direction of the vertical pressures be observed;
this result is obtained by the plug being supported by a fixed socket similar to the
box K, against which is pressing either a ring H or a ring H¹ fastened to the plug
of the cock.
The direction of the vertical pressure is completely ensured by the valve F, which
maintains a direct communication between the condensers and the atmospheric air
or the water cistern so long as the pressure in the condensers is inferior to that of
the atmospheric air. It is also ensured by the small tube », or any other arrange-
ment which gives access from the upper part of the plug to the cistern, or, if
preferred, to the external air.
The box screw K carries a graduated toothed wheel, which gears with a small
worm J intended to facilitate the exact adjustment of the vertical position of the
plug in the shell, even when the apparatus is in motion.
The plug of the cock is driven by a wheel and an endless screw; it carries on its
shaft the conical box W of the toothed wheel Y, which is so adjusted by means of
a key that both shaft and wheel inust turn at the same time, thereby permitting the
former to slide up and down independently from the wheel Y, as shewn, Fig. 1. A
spring X presses the wheel Y into its seat, mado in the socket of the arch E.

page_text: The pressure of the endless screw can be resolved into two others, one of which
is acting in the direction of the axis of the worm, and the other perpendicularly
to such worm; the former drives or actuates the wheel, thus imparting to it a
rotary motion, while the latter has no other effect than to produce a slight friction
in the box W.
If the pressure acting perpendicularly to the endless screw were not counter-
balanced by the box W, it should be transmitted to the plug of the cock, and would
thereby cause considerable friction.
It is not absolutely necessary to adhere to this combination or arrangement, con-
sisting of a conical box W, cast with the wheel Y, in one piece or otherwise, and
adjusted with a slight friction to a perfectly cylindrical part of the plug, in combi-
nation with a spring X, for maintaining the box W in close contact with its fixed
seat, made in the socket of the arch E. Other analogous constructions, although
different in appearance yet identical in principle, may be substituted for it. Thus,
for instance, the conical box W may be reversed and supported by a seat formed in
the upper portion of a prolongation of the shell. In this case its own weight would
suffice to insure its adherence to the seat, and the application of the spring X may
be dispensed with; or a box having a cylindrical outside and a conical inside may
be employed. This box would have to be adjusted to the socket of the arch E or
to an upper prolongation of the shell, so as to press with its inner conical surface
against a conical socket fixed to the shaft of the plug, either downwards by its own
weight, or in an upward direction by the action of a spring or counterweight.
All these devices may be employed with the same advantage, as it will suffice to
observe the following principle:-To receive the pressure of the part of the apparatus
that transmits motion to the plug by a socket which is capable of independent
movement in a vertical direction, and has a conical outside and a cylindrical inside,
or, vice versa, a cylindrical outside and a conical inside, which socket will be in any
case always perfectly adjusted to a corresponding cylindrical part, and maintained
in close contact with its inner or outer conical seat, either by its own weight or by
the action of a spring or counterweight.
By adopting one of the arrangements above described the plug may be actuated
by a bevil or ordinary toothed gearing, or by friction cones, or by straps.
The driving mechanism may be mounted either under the apparatus or above it.
The motive power may be derived from a small engine attached to the
apparatus.
It will be found advantageous to provide the interior of the shell with a seat of
brass or other inoxidizable metal. The plug of the cock may also be surrounded, if
necessary, by a covering of any inoxidizable metal in cases of feeding with water
containing corrosive matters.
The substances in solution contained in feeding water when being precipitated by
heat and evaporation occasion incrustations and sediments which are injurious to
boilers and necessitate a frequent cleaning of the latter. Carbonate of lime and
sulphate of lime may be mentioned as principally constituting these foreign matters
found to be dissolved in water, and which give rise to incrustations and deposits
when being precipitated by heat.
The carbonate of lime, of which great proportions are contained in water, is almost
entirely insoluble, it however may be found in solution in consequence of the
carbonic acid which is generally contained in water, and the presence of which
renders the carbonate of lime extremely soluble. When the water is heated and
maintained in a boiling state for a certain length of time all the carbonic acid
therein contained is disengaged, and consequently all the carbonate of lime in
solution is precipitated. As to the sulphate of lime it is soluble in water, but
like all the other salts of lime its solubility decreases rapidly and in proportion
as the temperature increases.
By the use of the improved feeding apparatus the water flowing from the cistern
into the condensing chambers C, C', will be firstly heated and maintained in ebul-
lition for a time, which will be the longer the greater the capacity of the condensers

page_text: is, and thereby causes the disengagement of the carbonic acid and the complete
precipitation of the carbonate of lime, which latter not being allowed to settle will
remain in a state of suspension. The feeding water is then supplied by the cavities
of the compartment B to the feeding openings or passages S, SI, where it is mixed
with the steam which rushes into the openings from the channels Z, Z', thereby
raising its temperature to that of the steam, and causing the precipitation of a
greater or smaller portion of the sulphate of lime which it contained in solution.
The feeding water thus separated from a great portion of its calcareous salts, but
still containing them in a state of suspension, deposits the salts in the separating
vessel D, and flows in a nearly purified state into the boiler G. I say "in a nearly
purified state," because it still will contain a certain quantity of calcareous matter
in suspension. This however cannot be of any consequences since the apparatus
not only purifies the feeding water, in the manner described, but also continu-
ously extracts at the same time both the salts which are precipitated in the
boiler, and those which have been precipitated when passing with the water
through the apparatus but not yet deposited on the bottom of the separating
vessel D. It is here indeed where the importance of the channels Z, Z, will
be perceived, as it is by then and the steain pipe V, which goes down to the
normal water line (which is continually maintained in the boiler by the apparatus)
that an incessant and rapid circulation of water from the boiler to the feeding
apparatus is produced. This water still containing in a state of suspension, both
the precipitated salts, which have not been deposited while passing the vessel D,
and those which have been precipitated after their concentration in the boiler,
is mixed with the feeding water issuing from the apparatus, and before returning
into the boiler leaves all the foreign matter behind it in the vessel D. In a word the
water of the boiler being continually sucked up by the pipe V, and again and again
caused by the channels Z, Z', to return through the vessel D, will always deposit in
the latter the foreign matters which have been disengaged from it. A transverse par-
tition L is fixed to the walls of the boiler a short distance below the steam pipe V.
This partition has the effect of producing the aspiration of the calcareous foam and
other impurities (floating on the water) by the steam pipe V. The same end is
attained by a tube Z' or similar connection. The circulation of the water from the
boiler through the pipe V and the channels Z, Z', or Z1, Z2, will be the more rapid
as the height or fall of water from the apparatus to the water line in the boiler is
more considerable.
The separating vessel D, as shewn in Fig. 7, consists of a simple cylindrical
reservoir divided into two portions by a vertical partition F, which forces the water
entering from the tubes S¹ to descend to the bottom of the vessel, and to deposit
there the earthy matter it contains; then to ascend on the other side, and finally to
flow into the boiler in a purified state. This vessel D may be conveniently modified
as its particular form is of no importance. and often it may be found advisable to
place in its stead a charcoal, slag, or pumice-stone filter.
Figures 8, 9, of the accompanying Drawings illustrate the apparatus as
arranged for heating the feeding water by the steam escaping from the engines. Fig. 9
represents a cross section along the line k, l, of Fig. 8, and the latter represents a
vertical section of Fig. 9, taken along the lines x, y, z, with a view to render the
operation of the apparatus more clearly intelligible. In this arrangement a sup-
plementary compartment A¹ is added to the compartments A and B. Two receivers
or chambers M¹, M', communicate by passages or openings m, m, m, with the cold
water cistern filled with water; the escaping steam enters into two other
chambers R, R, through the passages T, T, one of which is only visible in Fig. 8,
and is then discharged into the atmosphere through the tubes t, t. When the
apparatus is put in operation the cold water flowing from the cistern into the
chambers M, M, is supplied by the cavities of the compartment A' to the
receivers R, R, where it is heated by getting mixed with the escaping steam.
The water thus heated is conducted by the cavities of the compartment A into the
condensers C, C¹, and then carried by the cavities of the compartment B before the

page_text: steam and water passages V, S, from whence the feeding of the boiler or boilers
will take place in the manner before described. A waste pipe is fixed to the
passages U, U, which are cast in one piece with the openings intended for the
admission and emission of steam; the waste pipe prevents the latter from getting
accidentally choked up.
The apparatus, as shewn on the Drawings, is capable of distributing forty-five
litres (about ten gallons) of water when driven at a rate of twenty-five revolutions
per minute.
The peculiar features of novelty in my Invention as set forth in the above
description and shewn in the accompanying Drawings are,
First. The steam pipe descending within the boiler, not to the bottom of it, but
only to that low level below which a continued feeding of the water into the boiler
might become dangerous. This arrangement renders a retarded supply quite
impossible.
Second. The arrangement of the apparatus, as herein set forth, so as to permit of
the simultaneous feeding of any number of boilers with water without necessitating
the use of floats or analogous regulators of any description.
Third. Conducting the water (flowing from the cistern) into the apparatus by
means of descending pipes for the purpose of diminishing the violence of ebullition
of the water within the feeder.
Fourth. Placing the cone of the apparatus in an inverted position; that is, with
its largest diameter at its lower and not at its upper end, by which means the
capacity of the cavities of the lower compartment will be greater than that of the
upper compartment, and a constant vertical direction for the resultant of the pres-
sures will be thereby obtained.
Fifth. The adaptation to the apparatus of a valvo which will maintain a com-
munication between the condensers adapted to the apparatus and the open air or
the feeding cistern so long as the pressure in the condensers is inferior to the pressure
of the atmospheric air.
Sixth. The application to the apparatus of the water and condensing chambers
fixed to the corresponding apertures in the shell by means of bolts and flanges in lieu
of being cast along with the said shell in one piece, thus permitting them to contract
and expand without influencing or injuriously affecting the shell. Thin boards or
slabs consisting of any suitable material of bad conducting power are also adapted
to the apparatus with the view to protect the openings in the shell from any direct
contact with the water of the condensers and of the cistern.
Seventh. Maintaining a constant communication between the steam and water
openings or pipes, as described. These communications cause the steam pipes of
the apparatus to be continually cleared from any water, and thereby greatly increase
the distributing power or efficiency of the apparatus. Moreover they will enable
the apparatus to extract in a continuous manner the calcareous substances from the
boiler water, in which they are held in a state of suspension.
Eighth. The arrangement and form of the orifices of the steam and water openings,
the object being to augment the efficacy of the apparatus and to prevent jerks or
shocks taking place within the pipes.
Ninth. The inode herein set forth of isolating or protecting the interior of the
apparatus without using either packing or stuffing boxes.
Tenth. The application of a screw box in combination with a wheel and an
endless screw supporting the conical plug and permitting of its being properly
adjusted in the shell even while it is in motion.
Eleventh. The application of a conical socket for sustaining the pressure of the
part of mechanism that transmits motion to the plug.
Twelfth. The arrangement and use of the apparatus hercin set forth for the purifi-
cation of the feed water of boilers by means of heat and ebullition, and the con-
tinuous extraction of the calcareous and other matter contained (in a state of sus-
pension) in the boiler water.
Thirteenth. The special arrangement, herein shewn and described, of the apparatus

page_text: for allowing of the utilization of the exhaust steam for the purpose of heating the
feed water.
Various other minor improvements which have also their importanco are set forth
in the Specification, and illustrated in the Drawings subjoined."
In witness whereof, I, the said Alfred, Dervaux, have hereunto, set my hand
and seal, the Twenty-third day of September, in the year of our Lord
One thousand eight hundred and seventy-eight.
ALFRED DERVAUX, (L.S.)