6,) is long and shallow, and the liquid rises nearly to it’s brim. In
this vessel is placed a _long_ hollow drum A B, covered with open
wire-work, or any kind of cloth of a very loose texture. This drum turns
slowly, on the hollow centre C, to which is fitted a stuffing box and
tube, connecting the drum A B, with the pump P; the latter worked by any
convenient power. The pump then, drives air, either hot or cold into the
drum, and thence through the interstices of it’s texture; where it comes
in contact with the liquid at _an indefinite number of points_, breaks
the films formed by the liquid, and, saturated thereby, passes into the
open air; thus occasioning a rapid evaporation, which might be increased
either by heating the liquid or the injected air, or both, _ad libitum_.
The whole idea consists in the multitude of points of contact between
the liquid and the drying medium.
OF
A CUTTING OR GRATING MACHINE,
_For Green Roots, Tobacco, &c._
This Machine is composed of a perpendicular axis A B, fig. 7, driven
with considerable velocity by any proper _geering_. C D is a vessel
formed something like a shoe with the toe cut off: its entrance D is
concentric with the shaft A B, and a weight _m_, fastened to it’s side,
_equilibrizes_ the weight of the eccentric part C. Around this vessel,
and concentrically with it, is placed a cylindrical _rasp_ or _grater_ E
F, consisting, here, of a number of _blades_ so grooved on one surface
as that by grinding them obliquely on the edge, each one shall form a
line of sharp teeth, which, combined with those of the other blades,
constitute a rasp similar to that used for powdering dye-woods; with
this difference however, that these blades have interstices between
them, through which the pulp escapes outwards, and thus the rasp is kept
clean at all times. When this Machine is used the roots are merely
thrown into the vessel D as into the hopper of a mill, and they are
pressed against the rasp _by their own centrifugal force_; which is made
as strong or weak as desired, by the greater or less velocity of the
Machine.
This Machine owes its origin to the decree of the French Emperor, for
encouraging the making of sugar from beet-root. With the other
mechanicians of Paris I was called upon, by a house engaged in that
trade, to try my hand upon it; and this Machine was the result. It acts
fast and well; and from being less liable to clog, than most of the
others, is I believe superior; though _this_ was never proved by any
comparative experiment. If it were desired to _cut_ any substance with
this machine, the blades would be sharp knives, instead of being
toothed; and they would be placed obliquely to the circumference: but
the process of _grating_ is that for which it was exclusively designed.
OF
A SCREW,
_With greatly diminished Friction_.
My readers will perceive, that I have altered the title given in the
prospectus to this Invention. It has been done in deference to the
opinions of some persons in high reputation in the mechanical world, who
hold that there can be no motion whatever without _friction_. For my own
part I am no believer in several sorts of friction: and must therefore,
require a new definition of friction, before I can flow with the stream.
As the question, however, is not yet before my readers, I shall wave the
discussion at present, and describe this invention, as introducing the
_rolling motion_ into the threads of a screw; thus taking away the
GREATEST PART of the friction on every supposition.
In Plate 12, fig. 8, A is the screw, and B C the nut, bored large enough
to receive the screw, bodily, _without any penetration of their
threads_. Nevertheless, these threads are made to occupy the same
length, in both screw and nut, as though they did enter each other: so
that the two parts running parallel to each other, leave a _square
interstice_ _b_, all along both nut and screw: into which balls of
brass, or _soft_ iron are introduced, which at once restore the
screw-property without it’s friction: a friction so considerable in the
common screw, that it always surpasses the effective power, since it
remains closed, (in a vice for example) while holding any object
squeezed with all the force a man can apply. I have mentioned the use of
soft balls: it is in order that they may _all_ act together, and work
themselves to a common bearing. It will appear by fig. 9, that the
_acting_ balls might, or perhaps ought to be, separated from each other
by a set of smaller ones; since in this case, the surface of the
touching balls move the same way, avoiding all friction between _them_;
and leaving the friction only between those surfaces that are exempt
from heavy pressure. These circumstances will be understood by
consulting the direction of the arrows in fig. 9; and I have added two
other sketches, to shew the principle in it’s application to _square
threaded screws_, as at fig. 10; or to oblong threaded screws, whose
threads penetrate each other, in fig. 12. I have further, in fig. 8,
sketched one of the methods I propose for supporting the weight of the
descending balls, and returning them again into the nut. Considering the
balls as a _fluid_, I have provided a rising column of them, which the
working of the screw downward will fill: and the weight of the balls
themselves will return them into the nut, when the screw is drawn
upward.
OF
A SIMPLE AND POWERFUL
MICROMETER.
This interesting Machine, see Plate 12, fig. 11, consists of a screw
divided into three parts, _a_, _b_, _c_; the first, _a_, is a mere
cylinder to _centre_ the screw at that end: _c_ is a screw of (suppose)
20 threads to the inch; and _b_ another screw of 21 to the inch. D E
represents the frame of the Machine, the part E being the _fixed_ nut of
the screw C, while the piece _f g_, forms the _moveable nut_ of the
screw C, carrying a finger _g_, along the graduated bar, E _g_ D. If
now, the screw be turned once round by the button H, it will have moved
_to the left_ 1/20 of an inch; while the nut and it’s finger _g_ will
have progressed on it’s screw 1/21 of an inch _to the right_: and the
difference 1/20 - 1/21 = 1/420 of an inch is what the nut _f_ has really
moved to the left, along the bar E g D. If therefore, the rim of the
button be divided into 100 parts, _one_ of these will represent 1/42000
part of an inch by this Micrometer: and I need not add, that this minute
portion may be rendered still more minute at pleasure. The means of
doing this are evident: It is only making the screws _b_ and _c_ _nearer
alike_ in fineness, or number of threads per inch; as 29 and 30, 30 and
31, &c.
I hope it will be understood, that I do not give any of these Machines
as the only examples I could furnish of the application of the
principles on which they are founded. This very Machine is not a
Micrometer _only_; it might be (if made in proper forms and dimensions)
a vice, a press, or other _power Machine_. It has been already hinted,
that change of form must remain to be considered hereafter.
I have chosen to bring forward this Machine at an early stage of the
work, because it has, inadvertently perhaps, been ascribed to another
person. I refer to an article in the celebrated _programme_ of M.
Hachette, of Paris; with which is combined an essay on the composition
of Machines, by Messrs. Lanz and Betancourt. In the article D 3, at page
10 of that work, are the following words:
“M. de Prony a trouvé une maniere de transformer le mouvement
circulaire, en un autre rectiligne dont la vitesse soit aussi petite que
l’on voudra;” and further on--“l’idée en est extremement simple,
heureuse; elle est d’ailleurs susceptible de plusieurs applications
utiles aux arts.” And in page 11, are these words--“C’est ainsi que M.
de Prony est parvenu à une solution aussi simple qu’ingenieuse du
probleme qu’il s’etoit proposé.”
For the sake of my English readers, I subjoin a translation of these
passages: “Mr. de Prony has found (or invented) a manner of
transforming a circular movement into a rectilinear one, of which the
velocity shall be as small as may be desired;” and further on “This idea
is extremely simple and happy: and is besides, susceptible of several
useful applications to the arts.” And in page 11, are these words--“Thus
has Mr. de Prony given a solution as simple as it is ingenious, of the
problem which he had proposed to himself.”
The above account appears in 1808, and M. de Prony does not prevent or
disavow it. Perhaps he had forgotten the circumstance: and perhaps he
did not know of this publication: but I solemnly declare that I shewed
HIM this Micrometer, executed, _fourteen years before!_ that is, while
he and M. Molard were making their report on the Machines proposed for
the Water-works at Marly. I certainly wish to accuse no body in this
affair: but if I did not state the fact as it is, I should, myself, be
stigmatized as a _plagiary!_ I am _forced_, therefore, to take my stand
on the adage--“Fiat justitia ruat cœlum.”
In closing the first Part of this Work, I cannot but express my
gratitude for the unexpected _degree_ of support, with which my numerous
Subscribers have honoured me. I presume to offer these pages as a _fair_
Specimen of what they may expect in the four succeeding Parts,--namely,
as it regards the execution: for the _materials_ of what remains,
include objects of greater importance than those preceding. If I have
been fortunate enough to raise any favourable expectations in the minds
of my present readers, I hope they will express those feelings; and thus
induce others to join in bringing to a useful close, a work which is at
least _intended_ to produce unmixed public utility. From criticism, I
expect candour: and should my intentions, though pure, be
misrepresented--should envious tongues or pens assail my labours, or
asperse my character, I will defend both, _after_ I can use my Book as
my shield--that is, after I have fulfilled my Engagements with my
Subscribers: of whom (in expectation of meeting them again _within_
three months) I now respectfully take leave.
J. W.
_No. 5, Bedford-street,_
_Chorlton Row._
SYNOPSIS,
(IN ALPHABETICAL ORDER)
OF THE
_CENTURY OF INVENTIONS_
COMPOSING THIS WORK.
_Note. The objects with Numbers after them are those contained in the
present_ PART: _and the Numbers shew the Pages where they stand._
A
1 Adding Machine; or Machine to cast up correctly large columns of
figures.
2 Air Pump; essay towards completing the vacuum.
B
3 Barrel Spring, to lengthen the going of Clocks and other spring-
driven Machines. 26
4 Boats (serpentine) for lessening the expence of traction.
5 Bobbin or Lace (Machine for making) and for covering Whips, &c.
with great rapidity.
6 Bowking Machine for Calico Printers.
7 Bucket Wheels (a combination of) to raise water.
C
8 Canals (open) as Hydraulic Machines of great force.
9 Canter, or inclined Plane for Draymen. 72
10 Chain to act _equably_ on my wheels.
11 Chocolate Mill (rotatory.)
12 Cocks (_equilibrium_) to avoid leakage.
13 Colour Mill for Calico Printers.
14 Compasses (bisecting.)
15 Cotton (Machine for batting.)
16 Crane, combining _variable powers_ with speed and safety.
(rewarded by the Society of Arts.) 57
17 Crank (epicycloidal) or parallel motion. Rewarded by BONAPARTE. 30
D
18 Dash Wheel for Calico Printers, acting with greater rapidity than
usual.
19 Differential Wheels for gaining immense power. 54
20 Doffing Machine, of great force for taking Cylinders from their
Mandrills.
21 Draw-bench for my twisted pinions.
22 Dynamometer, for measuring powers and resistances in motion. 15
23 Dynamometer, second kind.
E
24 Engine for cutting my _Patent Wheels_ in small and middling
dimensions.
25 Engine for cutting my large bevil Wheels and wooden Models, either
on my System, or the usual one.
N. B. These objects will occupy considerable space in the work.
26 Engraving Machine for Calico Printers, being an important
application of my Cog or toothed Wheels.
27 Engraving Machine for large patterns.
28 Essay to _derive_ power from expanding Solids.
29 Evaporation (Machine to promote.) 78
30 _Eyes_ (Machine for making rapidly.)
F
31 Fire escape (on a retarding principle.)
32 ---- (by breaking the fall.)
33 Fires (Portable Engine to extinguish.)
34 Fires (Watch Engine always ready for.)
35 Flax (Machine for breaking) with rapidity.
36 Forging Bar iron and steel (Machine for.)
37 Friction (to prevent.)
38 Friction (to prevent) Thoughts on.
G
39 Geering and ungeering (Machine for).
40 Do. Do. for swift motions.
41 Grating or cutting green Roots, Tobacco, &c. (Machine for.) 79
H
42 Helico-Centrifugal Machine, for raising water in large quantities.
43 Horse Wheel for saving room and gaining speed. 53
44 Horse Wheel (reciprocating) for Mangles, &c.
45 Horse Wheel, with means for turning the Horse when he acts in two
directions.
46 Horizontal Pump of large produce, driven by wind.
47 Hot Air as _power_, while heating liquids, rooms, &c.
L
48 Lamp for the Table; suspending the oil by it’s weight.
49 Lithographic, or Copper-plate Press, with several curious and
useful properties.
M
50 Machine for clearing turbid liquors.
51 Machine for driving Boats on Canals, under Tunnels, &c. without
disturbing the Water.
52 Machine to assist in taking Medicine, Pills, &c. (Humani nihil
alienum.)
53 Mangle (perpetual or rotatory).
54 Marine-Level (two essays on a.)
55 Micrometer for measuring very minute spaces. 83
56 Mirrors to collect Solar Heat, (method of forming.)
57 Mover, by dropping weights. 76
N
58 Nails (Machine for moulding.)
59 Nails (Machine for forging.)
P
60 Pencyclograph, or Instrument for describing portions of Circles,
and finding their centres by inspection. 51
61 Peristaltic Machine, for raising _much_ water, to small heights.
69
62 Persian Wheel modified, for raising water.
63 Pitch-fork, for musicians, with variable tones.
64 Power-wheel by heated Air. 43
65 Press, direct and differential. 66
66 Press (eccentric Bar.)
67 Printing Machine (two coloured.)
68 Protracting Motion (Machine for.) 49
69 Pullies (my Patent much improved.) 33
70 Pump (my equable.) 45
71 Pump, triple, in one column.
72 Pump (portable) worked by pedals.
73 Punch Machine for Engravers.
74 Punch Machine on another principle.
75 Do. rotatory, for my Engraving Machine.
R
76 Reciprocating Motion, (long) for Mangles, &c.
77 Reflector parabolico conical, or plano parabolical for light
houses, &c.
78 Regulator: (not centrifugal) for Wind or Water Mills, Steam
Engines, &c.
79 Retrographic Machine (Machine for Writing backwards) for
Engravers.
80 Rotato-gyratory Churn.
S
81 Screw, with greatly diminished friction. 81
82 Screws, (Machine for forging) &c.
83 Spinning Machines, (my Patent), Eagles, &c.
84 Spinning Machinery: another system, adapted chiefly to wool.
85 Spring, to keep a door strongly closed, yet open easily.
86 Steel Yard, differential: for weighing _vast_ weights with short
levers.
87 Syphon, (mechanical) to expel part of the water at the highest
point.
T
88 Tallow (Machine for cutting and trying.)
89 Tea-table (commodious help for the.)
V
90 Ventilator, rotatory, yet by pressure.
91 Vessel (expanding) for Pumps, Steam Engines, &c.
W
92 Washing Apparatus: for Hospitals, &c. _confining the offensive
matter until cleansed away_: thus promoting salubrity.
93 Water-wheel, (horizontal) probably the best of the impulsive kind.
94 The same, for high falls.
95 Water-wheel, (inclined) employing the weight of the fluid.
96 Water, (Machine for raising large quantities.)
97 Weaving by Power: manner of driving the Shuttle, (executed A. D.
1780.)
98 Wedge Machine (perpetual.)
99 WHEELS (my System of cog or toothed.)
100 Windmill of great power.
ERRATA.
Page 16, line 17, for fig. read plate.
„ 22, „ 4, for posistion, read position.
„ 22, „ 7, for 17, read 15.
„ 22, „ 9, for fig. read plate.
„ 22, „ 23, for fig. read plate.
„ 24, „ 16, for clylinder at P, read cylinder at K.
„ 24, „ 22, for fig. read plate.
„ 26, „ 16, for E, read C.
„ 28, „ 5, for diamenter, read diameters.
„ 35, „ 10, for inconvencies, read inconveniences.
„ 36, „ 8, for of pulley, read of the pulley.
„ 40, „ 25, for as, read of.
„ 41, „ 4, for loose 1; read loose --
„ 41, „ 5, for pulleys, read pulley.
„ 43, „ 18, for furnish surplus, read furnish a surplus.
„ 43, „ 22, for occpied, read occupied.
„ 46, „ 17, for power, read motion.
„ 49, „ 22, for diffential, read differential.
„ 55, „ 21, }
„ 55, „ 24, } for 20,200, read 20200.
„ 55, „ 26, }
„ 55, „ 28, for 99,990, read ,99990.
„ 58, „ 23, for figures, read figure.
„ 62, „ 2, end the quotation marks at “lifting.”
„ 62, „ 8, for gasping, read anxious.
„ 63, „ 7, for wishd, read wished.
„ 64, „ 2, for ladders, read ladder.
„ 66, „ 11, for occasionaly, read occasionally.
„ 67, „ 7, for G N, read L N.
„ 68, „ 2, for _two hundred_, read _three hundred_.
„ 75, „ 4, for 300℔s. read 100℔s.
„ 82, „ 16, for fig. 9, read fig. 10.
„ 83, „ 11, for an of inch, read of an inch.
PART SECOND.
A NEW CENTURY OF
Inventions.
INTRODUCTION.
In the progress of a work like the present, no competent reason could
have been assigned for omitting to bring forward _my System of Toothed
Wheels_, the Patent for which has lately expired:--a System which a few
years ago, excited in this town, so much interest, aroused so much
animosity, and was treated with so much illiberality:--But which, also,
was fostered with so much public spirit, tried with so much candour, and
adopted with so much confidence. It was I say, incumbent on me to bring
the merits of this System into public view, had it only been to justify
myself for proposing, and my friends for adopting it. But stronger
reasons point now to the same measure. From the intimate connection the
System holds with the subjects of this essay, it _must_ be often
adverted to; and I have been already obliged to speak of it in terms
which can hardly have been understood by those readers who had not
previously considered the general Subject. I should therefore be still
in danger of filling these Pages with unintelligible assertions, did I
not begin by marking out the foundations on which my statements are
built; or by explaining to a certain degree, the _Principles_ of the new
System. Without then abandoning the tacit engagement I have taken with
my unlearned readers--not to entangle them in too much theory, I think
it indispensable to quote the Memoir I read before the Literary and
Philosophical Society of Manchester, in December, 1815; which small
work will form the basis of the _practical_ remarks I shall have to make
on the subject, as _this_ work proceeds. The Memoir is thus introduced
in the transactions of that learned body:
MEMOIR
ON A NEW SYSTEM OF
COG OR TOOTHED WHEELS,
_By Mr. James White, Engineer._[1]
COMMUNICATED BY T. JARROLD, M. D.
(_Read December 29th, 1815._)
[1] N. B. A Patent was taken out for the Invention some years ago.
“The subject of this paper, though merely of a mechanical nature, cannot
fail to interest the Philosophical Society of a town like Manchester, so
eminently distinguished for the practice of mechanical science; unless
as I fear may be the case, my want of sufficient theoretic knowledge or
of perspicuity in the explication, should render my communication not
completely intelligible. To be convinced of the importance of the
subject, we need only reflect on the vast number of toothed wheels that
are daily revolving in this active and populous district, and on the
share which they take in the quantity and value of its productions; and
it is obvious that any invention tending to divest these instruments of
their imperfections, whether it be by lessening their expence,
prolonging their duration, or diminishing their friction, must have a
beneficial influence on the general prosperity. Now I apprehend that all
these ends will be obtained in a greater or less degree, by having
wheels formed upon the new system.
I shall not content myself by proving the above theoretically, but shall
present the society with wheels, the nature of which is to turn each
other in _perfect silence_, while the friction and wear of their teeth,
if any exist, are so small as to elude computation, and which
communicate the greatest known velocity without shaking, and by a steady
and uniform pressure.
Before I proceed to the particular description of my own wheels, I shall
point out one striking defect of the system now in use, without
reverting to the period when mechanical tools and operations were
greatly inferior to those of modern times. Practical mechanics of late,
especially in Britain, have accidentally hit upon better forms and
proportions for wheels than were formerly used; whilst the theoretic
mechanic, from the time of De la Hire, (about a century ago) has
uniformly taught that the true form of the teeth of wheels depends upon
the curve called an epicycloid, and that of teeth destined to work in a
straight rack depends upon the simple cycloid. The cycloid is a curve
which may be formed by the trace of a nail in the circumference of a
cart wheel, during the period of one revolution of the wheel, or from
the nail’s leaving the ground to its return; and the epicycloid is a
curve that may be formed by the trace of a nail, in the circumference of
a wheel, which wheel rolls (without sliding) along the circumference of
another wheel.
Let _A B_ (Plate 13, fig. 1.) be part of the circumference of a wheel _A
B F_ to which it is designed to adapt teeth, so formed as to produce
equable motion in the wheel _C_, when that of the wheel _A B F_ is also
equable. Also, let the teeth so formed, act upon the indefinitely small
pins _r_, _i_, _t_, let into the plane of the wheel _C_, near its
circumference. To give the teeth of the wheel _A B F_ a proper form,
(according to the present prevailing system) a style or pencil may be
fixed in the circumference of a circle _D_ equal to the wheel _C_, and a
paper may be placed behind both circles, on which by the rolling of the
circle _D_ on _A B_, will be traced the epicycloid _d_, _e_, _f_, _g_,
_s_, _h_, of which the circle _A B F_ is called the base, and _D_ the
generating circle. Thus then the wheel to which the teeth are to belong
is the base of the curve, and the wheel to be acted upon is the
generating circle; but it must be understood that those wheels are not
estimated in this description at their extreme diameters, but at a
distance from their circumferences sufficient to admit of the necessary
penetration of the teeth; or, as M. Camus terms it, where the
_primitive circles_ of the wheels touch each other, which is in what is
called in this country the _pitch line_.
Now it has been long demonstrated by mathematicians, that teeth
constructed as above would impart equable motion to wheels, supposing
the pins, _r_, _i_, _t_, &c. indefinitely small. This point therefore
need not be farther insisted upon.
So far the theoretic view is clear; but when we come to practice, the
pins _r_, _i_, _t_, previously conceived to be indefinitely small, must
have _strength_, and consequently a considerable _diameter_, as
represented at 1, 2; hence we must take away from the area of the curve
a breadth as at _v_ and _n_ = to the semidiameter of the pins, and then
equable motion will continue to be produced as before. But it is known
to mathematicians that the curve so modified will no longer be strictly
an epicycloid; and it was on this account that I was careful above, to
say that the teeth of wheels producing equable motion, _depended_ upon
that curve; for if the curve of the teeth be a true epicycloid in the
case of thick pins, the motion of the wheels will not be equable.
I purposely omit other interesting circumstances in the application of
this beautiful curve to rotatory motion; a curve by which I acknowledge
that equable motions can be produced, when the teeth of the ordinary
geering are made in this manner. But here is the misfortune:--besides
the difficulty of executing teeth in the true theoretical form, (which
indeed is seldom attempted), _this form cannot continue to exist_; and
hence it is that the best, the most silent geering becomes at last
imperfect, noisy and destructive of the machinery, and especially
injurious to its more delicate operations.