IMPROVEMENTS IN WINDMILLS
Year: 1852

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, RICHARD
ARCHIBALD BROOMAN, of the firm of J. C. Robertson & Company, of 166,
Fleet Street, in the City of London, Patent Agent, send greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Royal Letters Patent under the Great Seal of the United Kingdom of Great
Britain and Ireland, bearing date at Westminster, the Twenty-third day of
February, One thousand eight hundred and fifty-two, in the fifteenth year of
Her reign, did, for Herself, Her heirs and sucessors, give and grant unto me,
the said Richard Archibald Brooman, my exors, admors, and assigns, Her
especial licence, full power, sole privilege and authority, that I, the said
Richard Archibald Brooman, my exors, adññiors, and assigns, and such others
as I, the said Richard Archibald Brooman, 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, in the Islands of Jersey, Guernsey, Alderney, Sark, and
Man, and in all Her said Majesty's Colonies and Plantations abroad, the
Invention of "IMPROVEMENTS IN WINDMILLS," communicated to me by a certain
Foreigner residing abroad; in which said Letters Patent is contained a proviso
that I, the said Richard Archibald Brooman, shall cause a particular descrip-
tion of the nature of the said Invention, and in what manner the same is
to be performed, by an instrument in writing under my hand and seal, to be
inrolled in Her said Majesty's High Court of Chancery within six calendar
months next and immediately after the date of the said in part recited

page_text: 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 Archibald Brooman hereby declare that the nature of the said Inven-
tion, and in what manner the same is to be performed, are fully described
and ascertained in and by the present Specification thereof, reference being
had to the Drawings hereunto annexed, that is to say:-
The said Invention has relation to what are known as "horizontal wind-
mills, and consists of the improved method of construction represented in
Figures 1, 2, and 3, of the Drawings, Figure 1 being an elevation of the
improved windmill, complete; Figure 2, a horizontal section of the same; and
Figure 3, a side view of the revolving parts of the mill. A, A, is a platform,
erected at a convenient height above the level of the ground. B, B, is an
octagonal or other shaped windhouse, which is raised on the platform A. The
centre part of this windhouse is formed so as to allow the revolving part or
parts of the mill to work within it. C, C, are partitions, by which the wind
blowing against the sides of the windhouse is directed into the interior. The
partitions are placed tangentially to the circumference of the revolving part of
the mill, and the passage for the wind is gradually contracted from the point
where it enters the windhouse, to that at which it impinges on the vanes.
D, D, are doors or flaps in the partitions C, C, which serve to close the ends of
the passages between the compartments, and prevent the wind from obtaining
access to the interior of the mill when it is not required to be at work. E is
the main shaft from which the motion is communicated to the grinding
machinery, or other machinery to be driven. F, F, are circular frames or
rings bolted to the arms G, G, which radiate from the shaft E. H, H, are
curved or flat vanes or blades, which project inwards from the rings F, F, by
and between which they are supported. The number of these vanes may
be varied, but should generally be about twice that of the ingress apertures
formed by the partitions C, C, of the windhouse. The action of the windmill
is as follows:-Three sides of the windhouse (supposing it to be, as usual, of
an octagonal form) being always exposed to the prevailing winds, the wind
is deflected by the partitions C, C, through the passages between the said
partitions to the interior of the mill, on entering which it strikes against the
vanes or blades H, H, on their convex sides, and passing through between them
escapes on the opposite side, exerting during its escape a considerable effect on
the concave side of the blades H, H, and thereby increasing the rapidity of the
revolution of the moving parts. In order to direct a large volume of wind into
the windmill, sails may be extended as continuations of the partitions C, C, from

page_text: the windhouse in each direction. The power of the mill, or the rapidity of its
revolution, will thus be considerably augmented. The proportions of the
different parts of the mill may be varied indefinitely, as may also the number
of partitions in the windhouse, and of vanes attached to the revolving part
of the mill, which vanes may also be either straight or curved (the latter form
being, however, considered that which is best adapted for general purposes).
The diameter of the revolving parts of the windmill should in no case exceed
half that of the windhouse. When a windmill of this kind is employed on
board ship it will be better to dispense with the employment of the windhouse,
which would only increase the cumbrousness of the apparatus without aug-
menting its efficiency. As the vanes on both sides of the revolving part are in
operation at the same time, that is, part of the vanes being acted on by the
wind on the exterior, and a corresponding number by the wind passing
through the apparatus on the interior side, there will be no tendency to make
the vessel incline to one side, and the equilibrium is further sustained by the
centrifugal force of the blades during the revolution of the revolving part of
the mill.
And having now described the nature of the said Invention, and in what
manner the same is to be performed, I declare that I claim as the said Inven-
tion the employment in windmills of a windhouse, divided into partitions, with
doors or flaps therein for the passage of the wind to the vanes, in the manner
represented in the Drawings, and herein-before described.
In witness whereof, I, the said Richard Archibald Brooman, have here-
unto set my hand and seal, this Eleventh day of August, in the year
of our Lord One thousand eight hundred and fifty-two.
R. A. (L.S.) BROOMAN.
AND BE IT REMEMBERED, that on the Eleventh day of August in the