AN IMPROVED AUTOMATICALLY ROTATING INSTRUMENT APPLICABLE AS A TOY AND FOR THE DIFFUSION OF GASES OF COMBUSTION
Year: 1870

page_text: PROVISIONAL SPECIFICATION left by Robert William Fraser at tho
Office of the Commissioners of Patents, with his Petition, on the
19th October 1870.
I, ROBERT WILLIAM FRASER, of Edinburgh, North Britain, Master of
Arts, do hereby declare the nature of the said Invention for "AN IMPROVED
AUTOMATICALLY ROTATING INSTRUMENT APPLICABLE AS A TOY AND FOR THE DIFFUSION
OF GASES OF COMBUSTION," to be as follows:-
This Invention relates to the application to a gas burner or lamp of an
instrument which is capable of rotating on a centre of support for the
purpose of diffusing the gases of combustion and preventing them from
blackening the ceiling immediately above the lamp or burner.
This instrument will admit a variation of form, the essential principle
of its construction being that it shall present an inclined surface to the
ascending current of heated air which impinging on the inclined surface
will impart a rotary motion thereto.
In forming this instrument I take a disc of thin sheet metal, and I
make a cut through it taking the figure of a volute, commencing near the
centre and terminating near the periphery. I then draw. out the severed.

page_text: disc to the form of a spiral and set the metal to that figure, or I divide
the disc radially from near the centre to the periphery into, say, eight
equal parts, and bend these divided parts to an angle of say, forty-five
degrees. The disc so divided I mount upon a supporting point about a
foot more or less above the burner or lamp to which it is to be applied, and
to enable the disc to turn freely under the action of the ascending current
I may fit it with a glass centre to receive the supporting point. Discs
thus prepared I ornament by gilding or silvering or by applying thereto
enamelled or other bright colours; as therefore the discs rotate the
colours will blend and form a brilliant and attactive object. In place of
mounting these discs on a supporting point they may be suspended from
a pendent wire with the like result.
In adapting the rotary disc as a toy I may mount it on a rod standing
up from a box which forms an air trunk. This box being pierced with
holes immediately below the disc, and a bellows being connected with the
box, currents of air may be forced upwards and caused to impinge on the
suspended disc and give it a rapid rotation. The varied colouring of the
disc will give it a pleasing appearance so long as its rotation is main-
tained. A bellows enclosed in a box is substituted as a means of
producing a vertical current of air. The apparatus thus modified forms
a game or an amusing toy without the use of heat or flame or a current
of air produced by combustion. In this case the bellows is fixed in a
small box of a convenient figure and a few inches in size. The lid of the
box is perforated with minute holes around a moveable rod two or three
inches in height and having a sharp point; on this point is placed the
disc formed in either of the modes already detailed, and by means
of a handle near the bottom of the box to be pressed by the finger
the required air is forced by the bellows through the aforesaid holes
or perforations in the lid and causes the disc to revolve. This form
of apparatus allows of small fingers being fixed to the disc representing
human beings, horses, or other animals, which will move with the
revolution of the disc to which they are are attached. In this case
however it will or may be necessary that the spindle on which the
disc revolves be made to work in two sockets or on points one
over the over, so as to maintain the disc in the plane of the horizon
during its gyration or revolution, and this method of keeping the disc in
the same plane would likewise be required if figures were placed upon it
when used over the flame or in the current of warm air, as already,

page_text: described. In this form the contrivance constitutes a game to be
employed for amusement. By placing an index in the centre of the disc
and working the bellows the index is made to perform several revo-
lutions, and on stopping it will point to such parts of the circumference
of the box as shall have been previously chosen as his own by some one
or other of the players, who thus becomes the possessor of the pool or
deposits which it may have been agreed upon to make. I will remark
that by allowing the rod on which the disc is mounted to pass through
the disc it may be used simply as a guide allowing the disc in its
rotation to rise and fall according to the variations of pressure of the
impinging air.