A MODE OF OBTAINING A MOVING POWER BY VOLTAIC ELECTRICITY, APPLICABLE TO ENGINES AND OTHER CASES WHERE A MOVING POWER IS REQUIRED
Year: 1841

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
PETRIE, of Croydon, in the County of Surrey, Gentleman, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent under the Great Seal of Great Britain, bearing date at Westminster,
the Twenty-seventh day of April, in the fourth year of Her reign, did, for
Herself, Her heirs and successors, give and grant unto me, the said William
Petrie, Her especial licence, that I, the said William Petric, my exors, adiñors,
and assigns, or such others as I, the said William Petric, my exors, adñiors,
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 use, exercise, and vend, within England, Wales, and the
Town of Berwick-upon-Tweed, and in the Islands of Jersey, Guernsey,
Alderney, Sark, and Man, and also in all Her Majesty's Colonies and Planta-
tions abroad, my Invention of "A MODE OF OBTAINING A MOVING POWER BY
VOLTAIC ELECTRICITY, APPLICABLE TO ENGINES AND OTHER CASES WHERE A MOVING
POWER IS REQUIRED;" in which said Letters Patent there is contained a proviso
obliging me, the said William Petrie, 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 inrolled in Her Majesty's High Court of Chancery within 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.

page_text: NOW KNOW YE, that in compliance with the said proviso, I, the said
William Petrie, do hereby declare that the nature of my said Invention, and
the manner in which the same is to be performed, is described and ascertained
as follows (that is to say):-
For the more clear understanding of the principle of my Invention, it may
be proper to state that the physical law rendered available by the machinery
is, that any conductor of electricity, as a metallic wire, transmitting an electric
current, tends to move either pole of a magnet in a direction tangential to the
circumference of the wire. Opposite poles are thus deflected in contrary
directions. Hence it follows as a consequence of the above law that a magnet
so supported as to be left free to turn in every direction, when acted on by a
wire transmitting an electric current, in all cases turns to set itself in a cross
position relatively to the wire. Now, I consider the most advantageous form
of machine for accomplishing the object of my Invention to be as follows,
reference being made by letters to the annexed diagrams, in order to render
the description more perfectly intelligible :--
Two rectangular helices [A, A, and B, B] crossing each other at right
angles, one helix [A, A], including the other [B, B], are fixed in a
suitable frame work (as represented in Figure 1). There is a hole [o] trans-
versely through the middle part of one end of each helix where they cross
the two holes, being in a line one behind the other, so as to allow an axis
[X, Y] to pass through. This axis extends along within the helices to where
they cross at the opposite end. The further extremity (✗] of the axis is
supported by and revolves in a suitable bearing [V] placed within the helices,
and that part [Y] of the axis which passes through the holes [0, 0,] may be
similarly supported either inside or outside of the helices [at W]. On that
part of the axis within the helices are placed magnets with similar poles
adjacent (of such a shape as N, M, S, the parts about N being north and
S south). Between every two magnets some soft substance, as pasteboard,
felt, or leather, is placed, to prevent vibration, and keep the magnets at proper
distances apart. The whole mass of magnets on the axes and within the
helices are inclosed in a drum or cylindrical case [R, R, R], to reduce as
much as possible the resistance of the air. An electro-magnet or electro-
magnets may be substituted for the above-mentioned permanent magnets.
They may be either of the same shape or of any other shape that may be
found convenient or desirable, and made as usual of soft iron bound round with
a ribbon of copper or copper wire, covered in a similar manner as the wires of
the helices [A, A, and B, B], the extremities of the ribbon or wire being
brought each to separate metallic rings fixed on the axis [X, Y], those

page_text: parts of the axis on which the rings are fixed being first covered by a noncon-
ductor of electricity, these rings being grooved externally to receive the ends
of conducting wires from a galvanic battery. In connection with the axis is
placed the current-changer [C, C, C], which consists of a cylinder [B, B] of
ivory fixed tight on an axis [E] which runs in suitable bearings [v and w],
which are attached to the frame work [C, C, C]. It is encircled at each end
by grooved copper rings [y, y, and 8, 8]; an inlaid strip [1] of copper extend-
ing one quarter circumference round the cylinder proceeds from one grooved
ring [y] (with which it is metallically connected) straight along the cylinder
to within a very small space of the grooved ring [8, ε]; on the opposite end
of the cylinder from which also similarly proceeds an inlaid strip [6] along the
opposite side of the cylinder. Upon each of the grooved rings [y, y, and 8, 8]
rest conductors or slips of slightly elastic copper ribbon [p and ], which are
attached to the frame work [C, C, C], and are respectively connected by
binding screws to the wires from the zinc and copper parts of a galvanic
battery or generator of electricity (lately named by Mr. Faraday the Rathode
and Anode). Four other conductors or slips of copper ribbon [ and, and ],
proceeding from the surrounding frame work, approach and touch tangentially
the inlaid cylinder, one at each quarter circumference. The conductors on
opposite sides of the cylinder [for instance μ and ] are connected by binding
screws to opposite ends of the same helix wire; hence as the cylinder [B, B
revolves along with the magnets [N, M, S,] (for their axes [ and X, Y]
are connected and revolve together) the current of electricity passes during
the first quarter of revolution through one helix, during the second through the
other helix, during the third again through the first-mentioned helix, but in the
opposite direction, and during the fourth quarter of revolution again through
the other helix, but in the opposite direction, the current-changer's inlaid
cylinder before mentioned being so placed with regard to the magnets that
they shall lie parallel with one helix in the middle of the time during which
the current passes through that helix, so that the tendency of the current at all
times shall be to deflect the magnets round in one and the same continued
direction. The current-changer's axis (ε) is connected with the magnet's axis
[X, Y], not rigidly, but by means of a sort of universal joint [Z], so that
none but a rotary motion may be communicated to the current-changer.
On that part of the axis between the current-changer and the helices there
is a pinion [P] connected with a larger wheel [Q, Q] or other contrivance,
causing the rapidly revolving magnet's axis to communicate a slower but more
powerful motion to another wheel or axis, which may be intended to do any
useful work.
:

page_text: MODE OF IREVENTING THE SPARK.
When a helix or even a long wire forms part of the circuit of an electric
current, on the circuit being interrupted a spark occurs, and hence a spark
would be produced on the current-changer's inlaid cylinder [5, 6] many times
in a second, which might soil and otherwise injure it; to avoid which a small
copper bridge [*] is placed, attached to a spring [*] in such a manner as to
press with both its ends on the inlaid ivory cylinder (but not so as to be in the
way of the conductors [,, and , ] from the helices, as it is nearer one end
of the cylinder, and stretching across a little more than a quarter of its circum-
ference, it is so placed that just before the current is to be turned off one
helix the revolving of the cylinder shall make a short circuit for the electricity
from one inlaid strip [1] to the other [*], across the bridge [x], then the further
revolution of the cylinder breaks the connection between the helix and battery,
and makes the connection with the other helix, and on the cylinder proceeding
round one of the inlaid strips [] next slides from under one end of the bridge,
and the circuit being very short produces little or no spark on being inter-
rupted. This one bridge [x], it will be seen, would be inoperative in the cases
of interruption of the current through the other helix, therefore a similar
bridge is placed on either quarter circumference adjacent to the first bridge.
(The two bridges must not be in contact, so as to allow electricity to pass from
one to the other.) There is also a second mode of preventing the spark. On
the inlaid cylinder, close and parallel to one inlaid strip [], and on that side
of it where the spark would occur, there passes a very narrow inlaid conducting
strip [], proceeding from the grooved ring [8] which is opposite to that
grooved ring from which the before-mentioned inlaid strip proceeds, and with
which it has no conducting communication. The ends of the conductors
[,, and ', ] must be in two parts (elastically connected), so that while one
part is just leaving the one inlaid strip [] (as the cylinder revolves) the other
part shall be just passing over the adjacent narrow inlaid slip []; the electricity
is now passing down one part [] of the conductor, and returns up the other
part [] (instead of passing through the helix, and returning by the opposite
conductor []. This being a short circuit little or no spark occurs when 'it
becomes interrupted by the further revolution of the cylinder. A second similar
narrow inlaid strip would be necessary [at ], if it were necessary to prevent
the spark when the motion of the engine was in the opposite direction. In
the foregoing description of the current changer and spark-preventers where
copper is mentioned any other suitable conductor of electricity will answer,
and where ivory is mentioned any other suitable non-conductor will answer.

page_text: OBSERVATIONS, DESCRIPTIONS OF ITS INDIVIDUAL PARTS, AND REMARKS ON THE
PROPORTIONS OF THE ENGINE.
The engine may be employed in such a position that the axis may be
horizontal (as represented in the design) or perpendicular, or at any imme-
diate angle. The parts exposed to much wear should be protected with casings
of any suitable material which could be removed when necessary, there should
also be oil boxes adapted to the engine, and such other means used to prevent
wear and friction as are known to engineers and others. In order to shew the
engine more clearly (in Figure 1), it is not represented so completely covered
as it should be. It is advisable to use iron as little as possible in the con-
struction of the engine, excepting for the magnets and axis. The helix frames
[E, E, and F, F], for keeping the helices in shape and protecting them from
injury, may be made of any convenient material, and of a rectangular form,
having a trough-like outer periphery, in which the wires are wound or bent
round. From the perforation [O] for the axis [X, Y) on the side of each
frame a piece of tube projects, which prevents the helix wire from passsing
over and covering the hole; and to afford room for the helix coils to pass at
this part the trough widens. The helix wire should be of pure softened
copper, and in large engines it may be of a flattened shape, to facilitate its
bending. There should be a good non-conducting material to prevent contact
between the coils, such as ferret, ribbon, or silk, or varnished or caoutchouched
cloth. The breadth of ribbon may be equal to the circumference of the wire to
be covered, if it is wound at such an angle as to lie double throughout. The
axis should be of the best steel. As little eccentricity of the centre of gravity
of the magnets would cause a great transverse strain, owing to the centrifugal
force, hence also the necessity of attention in fixing and balancing the magnets
accurately on the axis. The drum [R, R, R] which contains the magnets
may be made of metal sheet. It has a bottom, and through the centre of the
bottom is fixed a tube [D], with a longitudinal rib outside, which fits into
notches cut in the side of the hole in the centre of the magnets. The drum
should be prevented from revolving round the axis; as, for instance, by a pin
passing transversely through the part of the tube which projects beyond one
end of the drum, and through a corresponding hole in the axis. A cover or
end [T] should also be adapted, having small bolts to fasten into the side of
the drum. The conductors [μ, v, and π, T] may be divided longitudinally,
from within a short distance of the end which touches the current-changer's
cylinder, in several strips, so that each may be certain of being in contact with
the cylinder by reason of its own individual elasticity; otherwise the contact

page_text: might only take place perfectly at a single point. The current-changer's
cylinder would be best made of glass and palladium or some such materials,
harder and less easily affected by heat or liquids than ivory and copper. I
should recommend the electro-metallurgic process for attracting the metal to
the glass.
A little olive oil on the current-changer's cylinder reduces the
friction, and makes the action smoother; it does not materially impede the
circulation of the electric current. Daniell's constant battery, with wooden
diaphragms, appears the best calculated for the use of my engine. The
proportions which I conceive about the best for obtaining a given power,
taking into consideration both the expense and weight of the engine, also the
current expense and weight of the galvanic battery, are as follow:-
If the magnets be
The number of magnets on the axis (each being
as thin as can be conveniently be made) -
Occupying a space on the axis of
-
Helices to fit as close to the magnets as possible,
and their transverse sectional area to be
Helices to contain about 50 coils of wire
The current-changer should be as small as can
conveniently be used.
20 inches, there should be
40 or more.
8 inches.
5 inches in the side.
0.344 square inch section.
0.56 grains.
The galvanic battery should be capable of circulat-
ing as much electricity as results from the oxi-
dation of zinc, per second, of
The action of the battery will be reduced to about one half by the opposition
offered to the passage of the electricity by the helices, the electricity being of the
tension of a single cell. The engine should be worked at the greatest velocity
that may be found practically not to be productive of much inconvenience.
I do not claim as any part of my present Invention the employment of
helices transmitting electricity so as to deflect magnets placed in or about
them (that having been already done, for instance for the purpose of measur-
ing clectric currents), nor the use of the drum to enclose magnets, that they
may meet with less resistance from the air when revolving. Further, I do
not claim or confine myself to any particular shape of or substances for
making helices, nor to any particular shape, substance, or mode of magnetising
for the magnets they may be electro-magnets, as already mentioned, nor to
any particular form of current-changer (or apparatus for stopping or reversing
the electric current). And I do not claim as part of the present Invention for
which I have obtained Letters Patent my two herein-before described methods
of preventing the occurrence of electric sparks in current-changers, either of

page_text: which are, however, useful adjuncts to the particular form of my engine already
herein described. But what I do claim is, the application of the deflective action
which exists between electric currents and magnets for the purpose of obtaining
a moving power as above specified.
In witness whereof, I, the said William Petrie, have hereunto set my
band and seal, the Twenty-seventh day of October, in the year of our
Lord One thousand eight hundred and forty-one.
AND BE IT REMEMBERED, that on the Twenty-seventh day of October,
in the year of our Lord 1841, the aforesaid William Petric came before our
said Lady the Queen in. Her 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.
Inrolled the Twenty-seventh day of October, in the year of our Lord One
thousand eight hundred and forty-one.