VARIOUS IMPROVEMENTS IN THE FORM AND CONSTRUCTION OF WINDMILLS AND THEIR SAILS
Year: 1829

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, J, THOMAS
CHEEK HEWES, of Manchester, in the County of Lancaster, Engineer, send
greeting.
WHEREAS His most Excellent Majesty King George the Fourth, by His
Letters Patent under the Great Seal of Great Britain, bearing date at West-
minster, the Fourteenth day of January, in the ninth year of His reign, did,
for Himself, His heirs and successors, give and grant unto me, the said Thomas
Cheek Hewes, His especial licence, that I, the said Thomas Cheek Hewes,
my exors, adiñors, and assigns, or such others as I, the said Thomas Check
Hewes, my exors, adiñors, and 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, my Invention
of "VARIOUS IMPROVEMENTS IN THE FORM AND CONSTRUCTION OF WINDMILLS AND
THEIR SAILS;" in which said Letters Patent there is contained a proviso
obliging me, the said Thomas Cheek Hewes, by an instrument 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 enrolled in His Majesty's High Court of Chancery within

page_text: six calendar months next and immediately after the date of the said 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
Thomas Check Hewes, do hereby declare that the nature of my said Inven-
tion of Various Improvements in the Form and Construction of Windmills and
their Sails, for which I have obtained the said Letters Patent, and the
manner in which the said Improvements are to be conducted and carried into
effect, are clearly shewn in the Drawings hereto annexed, and the following
description thereof (that is to say):-
Figures 1, 2, 3, and 4, represent various views of my improvement for
varying the speed of the flour stones, machinery, or other work with which the
mill is connected, and thereby allowing the sails of the mill to move at a
greater variety of speeds than in mills of the ordinary construction. Figure 2
is a plan or part of the geering, in which A represents a section of the
perpendicular shaft connected by bevils in the ordinary manner to the wind-
shaft above. Through the shaft A power is conveyed to the horizontal
shaft B, and thence by the bevils at the further extremity of B to the shaft C,
and onwards to the work to be performed. This train of movements will also
be seen more plainly in the elevation of the same parts in Figure 4, and the
speed and proportion of wheels used are calculated for the ordinary velocity of
windmill sails; but my method of varying the speed, as before named, depends
on the annexed parts shewn in Figures 1, 2, and 3. Figure 1 is an elevation
of a carriage of wood or other suitable material which supports the perpen-
dicular shaft D along with the horizontal shaft E to which D is connected by
the bevils, as seen in Figure 1, and on the shaft E are placed the different
sized spur wheels represented at F, G, H, I. The whole of this carriage,
with its appendages, as represented in Figure 1, is placed parallel with the
shaft B, and supported in such position that the wheel K on the shaft D can
be brought into geer with the wheel L by raising the latter on the shaft A,
when required, by means of the bos of the wheel L, to which the wheel P is
also connected, sliding on the shaft A, as shewn in the transverse section of this
part at Figure 3, where the dotted lines shew the position of L when in geer
with the wheel K, in which position it can be keyed in the usual manner, when
required. It may also be observed, that when the wheels L and K are put
into geer the bevil P is at the same time out of geer. M, M, M, seen in
Figures 1, 2, 3, represent parallel arms, by means of which the whole of the
arrangements of parts represented at Figure 1 are held parallel to the shaft B,

page_text: see Figures 2 and 3. These arms M, M, M, vibrating on their fixed centres
at A and N, allow the shaft E to be receded or brought nearer to the shaft B
without varying the distance of the centres D and A, as will be more plainly
seen by reference to the dotted lines in Figure 2; and by the same action of
placing the parallel shaft E and B at any required distance, I am enabled to
to connect the wheel 0 (which slides on the shaft B) with any of the
wheels F, G, H, or I, and thereby vary the speed of the shaft E. By this
latter arrangement the motion imparted from the perpendicular shaft A
instead of proceeding through the bevil P to the shaft B and onwards, as first
described, is taken through the wheels L and K to the shaft E, as shewn at
Figure 1, from which shaft it is returned to the shaft B by some one of
the wheels F, G, H, or I, according to the speed required.
My next improvement, represented in Figures 5, 6, and 7, is for the
purpose of rendering the helm sails, or those small sails usually applied for
the purpose of keeping the main sails in the proper direction to the wind,
more efficient and capable of acting with a slighter variation of the wind than
those of the ordinary construction; and this I effect by the combination of a
vane or weathercock connected with the small helm sails of the ordinary
construction, but which, in consequence of this combination, may be made
much smaller than usual and still act with a better effect. Figure 5 is an end
view; Figure 6, a side view; and Figure 7, a plan of the same part.
QQ, Q, Q, represent the usual framing projecting from the back of the
mill-head, and R the small helm sails, by means of which the main sails are
kept to the wind; and the wheels and shafting by which this effect is produced
are of the ordinary arrangement and constructions, but the small helm sails R,
along with the upper part of the geering, instead of being attached to the
framing Q, Q, Q, Q, are supported in the frame S, S, S, S, see Figure 5, and
allowed to vibrate or move horizontally on the centre T; the position of these
small helm sails, with respect to their perpendicular centre being determined
by the position of the vane or weathercock U to which it is connected, as
shewn in Figures 6 and 7. Thus, suppose the wind to blow in the direction
of the arrow seen at Figure 7, which would scarcely effect a stationary helm
sail, the broad surface of the vane or weathercock U would be carried in the
direction of the dotted lines in Figure 7, and by its connection with the small
helm sails R, place them in the position as also shewn in dots in the same
Figure, and thereby enable them to receive the effect of the wind in a much
more direct manner than if they had remained stationary, as in the ordinary
construction; and supposing the wind to vary in either direction in ever so
slight a degree, the broad flat surface exposed by the vane or weathercock U

page_text: will be immediately acted on, and the small helm sails brought into action,
which will again be put out of action by the same means, as soon as the
weathercock or vane shall have resumed the position shewn in Figures 6
and 7. My improvement on the sails of windmills (by which I mean the
main sails which do the work) consists in a certain construction or arrange-
ment of parts by which I brace or frame the sails much stronger, with less
material, and expose a much greater surface to the wind, thereby rendering
them of considerably less weight and more effective. Figure 8 represents a
front view of the framing of the arms or whips for eight sails, to which the
cloth or weather boards are to be attached, part of the whips or arms
marked Y, being broke off as unnecessary for the explanation. The number
of sails may be varied at pleasure, and as much of the whole surface con-
tained in the circumference of the sails filled with cloth or board, as may be
required. Figure 9 is a sectional side view of the same; and Figure 10 is a
back view on a smaller scale to shew the general effect when the sails are
clothed or boarded. In constructing these sails I have formed the bos or
flange to which the whips are attached of cast iron, as shown at V, V, V,
in Figure 8 and 9, where it will be seen that the whips do not radiate from
the centre of the wind shaft W, but from a point near the circumference of
that shaft, and that the back whips or arm, tinted red in Figures 8 and 9,
intersect the front whips at a short distance from the centre. This is effected by
using the same bos or flange reversed for both the front and back set of whips
or arms, so that the back and front whip or arm which belongs to each sail
radiate from points on the opposite sides of the circumference of the wind shaft;
and the iron braces X, which are attached to each of the whips or arms for
the purpose of strengthening them, are at their opposite extremity attached to
the opposite flange or bos to which the whip or arın is connected. By
reference to Figure 9 it will be seen that neither the front or back arms of the
sails are at right angles to the wind shaft W, but gradually approach each
other towards their outward extremity, thereby forming the requisite inclination
of each respective sail, which inclination can be varied as circumstances may
require, by increasing or diminishing the distance of the two bos's or flange
pieces V on the wind shaft; but this, as well as the angle formed by the back
and front whip or arm of each sail, can be varied as required; the proportions
which I have found answer for the latter for sails of sixty feet diameter, are as
follows:-
First, divide the diameter into eight parts, and take three parts for a pitch
diameter, then let a line, produced from the back and front arm or whip of
each sail, unite in the pitch line or diameter, which will give the angles

page_text: formed by the whips or arms with. each other. To make this more clear, see
Figure 10, where the dotted lines a, a, are produced from the arms or whips
of the sail on the opposite side of the wind shaft, and unite at c in the pitch
circle b, b, b, b, which is three eighths of the whole diameter of the sails.
As regards the form of windmills erected with my various improvements above
described, I am not limited to the ordinary circular form in which they are
usually constructed, which form is the result of the lengthened sails, which
necessarily require a circular building to allow of turning to face the wind in
any direction it may blow; but from the increased amount of surface exposed
in sails on my construction, a much shorter length of whip, arm, or diameter,
is sufficient for the same amount of power, and I am thereby enabled to
place a small lantern tower for the purpose of carrying my sails on any build-
ings, of either an oblong, square, or other convenient shape, and am in no way
confined to the inconvenient, expensive, and crowed form of ordinary circular
windmills, to which, nevertheless, my improved sails are in every way appli-
cable, as they may be fixed on the old wind shaft; and it is by this application
to windmills already in existence that I consider them of the most extensive
importance. I would also recommend their utility to water mills, where from
floods or scarcity of water during the summer, is often impeded, under which
circumstances they would enable the miller, in many cases, to gain considerable
additional power. This latter application of my improved sails I have already
applied in aid of steam engines, where it is found of great advantage and an
immense saving in the expenditure of fuel.
Having now described my Various Improvements in the Form and Con-
struction of Windmills and their Sails, I do hereby declare that I do not
claim any separate portion or part of such machinery, but I do claim such
combination or arrangement of parts as herein-before described, by which my
various improvements are effected.
And lastly, I declare that the speeds and general construction of the
various parts of my improvements herein-before described may be modified
and varied; all which modifications and variations producing the same effect
and results may be attained by any person of competent skill, and fit to be
entrusted with the construction of machinery of this or a like description.
In witness whereof, I, the said Thomas Cheek Hewes, have hereunto
set my hand and seal, this
day of July, One thousand eight
hundred and twenty-nine
THOMAS CHEEK (L.s.) HEWES.

page_text: AND BE IT REMEMBERED, that on the Ninth day of July, in the year
of our Lord 1829, the aforesaid Thomas Cheek Hewes came before our
said Lord the King in His Chancery, and acknowledged the Specification
aforesaid, and all and every thing therein-contained and specified, in form
above written. And also the Specification aforesaid was stamped according
to the tenor of the Statute made for that purpose.