CERTAIN IMPROVEMENTS IN EVAFORA- TION
Year: 1833

page_text: TO. ALL 10 WHOM THESE PRESENTS SHALL COME, I, WILLIAM
GODFREY KNELLER, of Mitcham, in the County of Surrey, Chymist, send
greeting.
WHEREAS His present most Excellent Majesty King William the Fourth,
by His Letters Patent under the Great Seal of Great Britain, bearing date at
Westminster, the Twenty-fourth day of August, in the fourth year of His reign,
did, for Himself, His heirs and successors, give and grant unto me, the said
William Godfrey Kneller, His especial licence, full power, sole privilege and
authority, that I, the said William Godfrey Kneller, my exors, adñors, and
assigns, or such others as I, the said William Godfrey Kneller, my exors,
adñiors, 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 expressed, should and
lawfully might make, use, exercise, and vend, within England, Wales, and the
Town of Berwick-upon-Tweed, and also within all His said Majesty's Colonies
and Plantations abroad, my Invention of "CERTAIN IMPROVEMENTS IN EVAFORA-
TION;" in which said Letters Patent is contained a proviso that I, the said
William Godfrey Kneller, shall cause a particular description of the nature of
my said Invention, and in what manner the same is to be performed, to be
inrolled in His said Majesty's High Court 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.

page_text: NOW KNOW YE, that in compliance with the said proviso, I, the said
William Godfrey Kneller, do hereby declare that the nature of my improve-
ments in evaporation consists in the employment of certain apparatus or
machinery, whereby I am enabled to effect the sudden compression of common
atmospheric air, conveyed by means of inverted moveable chambers or ventila-
tors filled therewith, and depressed below the surface of the heated fluids or
liquids to be evaporated, and which said volumes of air becoming suddenly
expanded by the heat of the said fluids or liquids, pass underneath the lower
edges of the said inverted chambers into the adjoining chambers, and pass
off through holes or apertures provided in the upper parts of the said cham-
bers, and through the superincumbent fluids or liquids loaded with the
aqueous or other vapours, and upon these chambers or ventilators being raised
or elevated above the surface of the said fluids or liquids they again become
filled with fresh air, and which is also on its turn conveyed beneath the surface
of the fluids or liquids by repetition of the movement of the ventilators, and
thus a continual and rapid evaporation of the said fluids or liquids is produced,
as, whilst one part of the said ventilators is plunged into the fluids or liquids
to be evaporated, the other half is raised above their surface and is receiving
volumes of fresh air. I do not mean to claim as my Invention any particular
forms or shapes of this said apparatus, but to avail myself of any which may
be fit and proper for the purpose, and shall vary them according to the
description of bodies or other apparatus, they are to be applied to. For instance,
in the evaporation of brine in salt works in flat-bottommed pans, I shall employ
it in either of the forms shewn in the annexed Drawing, in which Fig. 1 is
a side elevation, Figure 2 an end section, and Figure 3 a plan of a salt pan
fitted up with one of my ventilators. A, B, in all the Figures, is the pan
which is either to be set or mounted in brickwork as usual, with the fire or
fires underneath it, or be heated in any other manner. C, C, in Figure 2,
indicate the height of the brine. D) represents the ventilators or moveable
inverted chambers, one part of them being shewn by dotted lines as plunged
beneath the surface of the brine, whilst the other part is shewn as raised
above its surface, and receiving air ready to be plunged into the brine in its
turn; the form of them is also shewn in the section at D. These ventilators
are here shewn as being constructed of iron, and as mounted upon a shaft or
axis F, furnished with proper pivots and bearings. In the said section D,
G is one of the inverted chambers closed at top, but which, in certain cases,
may have small pin holes made in it to relieve any pressure upon the boxes,
and H, one provided with holes or apertures I along its top part, as is more
clearly shewn in the plan, Figure 3, at I, I, I, I, I, I, I, I, I. Figure 4 is an

page_text: end section of an apparatus similar to that shewn in Figure 2, excepting that
the form of the ventilators differs in the air chambers. being equally deep in
the centre and on each side of it, instead of their being deeper on each side
than in the centre, as in Figure 2. The same letters of reference indicate the
similar parts in both Figure 2 and 4, and as well also 1 and 3, and the
other Figures. Instead of forming the ventilators of portions of cylinders, I
can also make them of entire cylinders mounted upon proper shafts with
pivots and bearings, and as shewn in the side elevation of Figure: 3, and in a
plan thereof at Figure 6, the holes for the escape of the air I, I, &c., being
also shewn in the interior or hollow part of the said cylinders, as in the
ventilators above mentioned; and I can either place them at regular intervals
across the pan, as shewn in Figures 5 and 6, or lengthwise, as in Figures 1
and 3, and either cause them to vibrate or revolve continually, as may be
found convenient; and instead of making the ventilators cylindrical, or portions
of cylinders or other curves, I can also form them in a flat shape and, as
shewn in plan at Figure 7, and in a section at Figure 8, taken at the dotted
line in Y, Y, in Figure 7, Figure 9 being in cross section taken at the dotted
line K, K, in Figure 7, and cause them to be raised and lowered in a vertical
position by any proper machinery, which need not be described here. I can
also make the flat-shaped ventilators of a round, oval, or other form, as well
as of the square form here shewn, as occasion may require, and instead of
using iron, as above mentioned, I can employ any other metal, or mixtures of
metal, or wood, or indeed any fit and proper material or materials, according to
the nature or purpose to which they may be applied; as, for instance, in the
evaporation and concentration of brine, solutions of salts, medical extracts, salt-
petre, and alum works, the manufacture of sulphuric acid, oxalic acid, the
acetates of soda and lime, and other similar purposes; also in the distillation
of acetic and pyroligneous acids, and of ardent spirits, and in the concentration
of weak wines, cyder, and perry; likewise in the cooling by evaporation of
brewers', distillers', and vinegar makers' worts or wash; also in glue and
soap making, colour making, and indeed in all cases where evaporation
forms an essential part of the process or processes; and I can also employ
them in the generation of steam in closed vessels, or in vessels partly closed,
my claim being for the conveying air beneath the surface of fluids, not by
blowing, as heretofore done, but by means of the ventilators or inverted cham-
bers herein described, and displacing the fluids or liquids, and which said air
escapes through the apertures made in the upper parts of the said chambers
loaded with the aqueous or other vapours, and also passes through the superin-
cumbent fluids or liquids, thereby promoting the rapid evaporation of such

page_text: fluids or liquids, and also cooling the said fluids or liquids according to the
well-known effects of evaporation. In the case of generating steam in low-
pressure boilers I can employ the vibrating ventilators D, D, in the manner
shewn in Figure 10, which is an end section of such a boiler, one of them
being immersed in the water, and the other elevated above it, or employ a
revolving ventilator in a similar way to that shewn in Figure 11, which is an
end view and section, and Figure 12 a longitudinal view and section of a
revolving ventilator D, as applied to a still, in order to promote evaporation
therein; and it is also evident that either the vibrating or the revolving
ventilators may be employed in generating high-pressure steam in boilers made
in proper forms and strength. In cases, however, where the ventilators are to
be employed in stills or steam boilers, it will be necessary that their shaft or
axis be made cylindrical, and be passed through stuffing boxes to prevent the
escape of vapour or steam thereby, and that where cooling is to be performed
the operation may be effected in the usual open vats or other vessels commonly.
employed, the air introduced by the ventilators producing its well-known
cooling effect by evaporation.
In witness whereof, I, the said William Godfrey Kneller, have hereunto
set my hand and seal, this Twenty-fourth day of February, in the year