Scientific American Supplement, No. 358, November 11, 1882
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Various >> Scientific American Supplement, No. 358, November 11, 1882
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The press under consideration is well adapted to the treatment of heated
seed paste, and has been very successfully employed for that purpose
in France, Belgium, and Holland. It succeeds equally well for the
extraction of oil from nuts. Referring to the drawings, the scales are
for Figures 1, 2, 3, 4, 14, 15, one fifteenth actual size; Figures 5, 6,
7, 8, 9, one-tenth; Figures 10, 11, 12, and 13, one-fifth.--_Machines,
Outils et Appareils_.
* * * * *
LAURENT & COLLOT'S AUTOMATIC INJECTION PUMP.
As well known, in every well-constructed injection pump, there is a
system of gearing which acts upon the suction valve and stops the
operation of the pump as soon as the requisite pressure is reached;
but the piston, for all that, continues its motion, and, besides the
resistant work of the pump has passed through different degrees of
intensity, seeing that at every moment of its operation the piston
has preserved the same stroke and velocity. We are speaking, be it
understood, of pumps that are controlled mechanically. In the one that
we are about to describe, things take place far otherwise. In measure as
the pressure increases, the stroke of the piston diminishes, and when it
has reached its maximum, the motion of the piston ceases entirely. If,
during the operation progression undergoes more or less variation,
that is, for example, if it diminishes at a given moment to afterwards
increase, the stroke of the piston undergoes all the influences of it.
The pump of which we speak is shown in Figs. 16 to 21, and is the
invention of Messrs. Laurent Bros. & Collot. It may be described briefly
as follows:
The apparatus, as a whole, has for base a cast-iron reservoir; A, to the
top of which is fixed the pump properly so-called, B, as well as the
clack box, A, and safety valve. The pump is placed opposite an upright,
D, whose top serves as a guide to the prolongation, E, of the piston
rod. This latter is traversed by a pivot, a (Fig 19), on which is
mounted a lever, F, whose outer extremity is articulated with a
connecting rod, G, which is itself connected with the cranked shaft,
G. This shaft has for its bearings two supports, b, attached to the
reservoir, and carries the driving pulleys and a fly wheel. The beam, F,
having to give motion to the piston in describing an arc of a circle at
the extremity attached to the connecting rod, must, for that reason,
have a fixed point of oscillation, or one that we must consider as such
for the instant. Now, such point is selected on a piece, H, having the
shape of the letter C, and which plays an important part in the working
of the pump. This piece is really a two-armed lever, having its center
of oscillation in two brackets, c, at the base of the reservoir. Fig. 17
shows the relation of the beam, F, and lever, H. The upper extremity of
this latter is forked, and embraces the beam, F, whose external surfaces
are provided with two slots, d, in which to move slides, e, attached to
studs, f, which are perfectly stationary on the extremities of the forks
of the lever, H. One of the slots is shown in section on the line 1--2
in Fig. 20, and on the line 3--4 in Fig. 21.
Things thus arranged, if we suppose the piece, H, absolutely stationary,
it is clear that, as the oscillation of the beam, F, is effected on the
studs, f, as centers, the piston of the pump will perform an invariable
travel whose extent will be dependent upon its position between such
point of oscillation and the point of articulation of the connecting
rod, G. But we must observe that even according to such a hypothesis,
the point, f, would not be entirely stationary, because the point
of articulation, a, upon the piston rod being obliged to follow an
invariably straight line, the slots, d, will have to undergo an
alternate sliding motion on the slides, e, save, be it understood,
when the latter are brought to coincide exactly with the center of
articulation, a. Now we shall, in fact, see that the point, f, can move
forward in following the slots, d, and that it may even reach the point
of articulation, a, of the beam, F, on the rod, E, that is to say,
occupy the position shown in Fig. 18, where the oscillation of the beam,
F, being effected according to the point, a, the stroke of the piston
has become absolutely null.
The position of the piece, H, is, in effect, variable with the pressures
that are manifested in the pump. It will be seen that the latter has a
tubular appendage, g, in whose interior there plays what is called
a "starting rod," h, which is constantly submitted to the pressures
existing in the interior of the pump, and which rests against the lower
arm, H, of the piece, H. But this latter is also loaded at the opposite
side with heavy counterpoises, i, which counterbalance, within a
determinate limit, the action of the rod, h, that tends constantly to
cause the lever, H, to oscillate around its pivot, in the brackets, c.
To sum up, then, as long as the pressure in the pump has not reached a
determinate limit, the lever, H, held by its counterpoises, _i_,
will keep the position shown in Fig. 16, and for which the center of
oscillation, f, corresponds with the maximum stroke of the pump piston.
But as soon as such limit is exceeded, the equilibrium being broken, the
action of the rod, h, predominates, the piece, H, reverses from right to
left, the point of oscillation, f, moves forward in the slots, d, and
the stroke of the piston is reduced just so much. If, finally, the
pressure continues to increase, the motion of the piece, H, will
continue, and the point of oscillation, f, will reach the position for
which the motion of the piston ceases completely (Fig. 18).
But it results further, therefrom, that if when such position is
reached, the pressure diminishes, the lever, H, will, under the
influence of its counterpoise, tend to return to its first position and
thus set the piston in motion. As we remarked in the beginning, the
automatism of these functions is absolutely complete.
It will be remarked that the piece, H, is provided with an appendage,
H squared, whose interior forms a rack. This rack engages with a pinion, I,
mounted on an axle, J, which carries externally a fly wheel, K. This
axle, J, moves with the various displacements of the lever, and its fly
wheel overcomes by its inertia all backward and forward shocks resulting
from the thrusts due to the sliding of the steel slides in the different
positions of the connecting rods. Such shocks would make themselves
especially felt while the dead centers were being passed.
The velocity with which this pump runs varies from 75 to 80 revolutions
per minute. It easily gives a pressure of 200 atmospheres. With a
hydraulic press having a piston O.27 of a meter in diameter, it
permits of effecting in ten minutes the extraction of the oil from 25
kilogrammes of colza seeds. Referring to the drawings, the scales for
Figures 16, 17, 18 are one-fifteenth actual size, and Figures 19, 20,
21, one-tenth.--_Machines, Outils et Appareils_.
* * * * *
IMPROVED DREDGER.
We illustrate below a dredger of simple construction, well calculated
for doing useful work on shallow streams. The barge is 54 ft. long, 22
ft. beam, and 6 ft. deep. Her draught of water is under 4 ft. Built by
Rose, Downs & Thompson Hull. Our drawing explains itself. It will be
seen that we have here a swiveling crane and grab bucket, and that the
stuff dredged can be loaded into the barge and conveyed where necessary.
The lifting power of the crane is one ton, and in suitable material such
a dredger can get through a great deal of work in a comparatively short
time.--_Engineer_.
[Illustration: IMPROVED ONE-TON BUCKET DREDGER.]
* * * * *
HISTORY OF THE FIRE EXTINGUISHER.
The first fire extinguishers were of the "annihilator" pattern, so
arranged in a building that when a fire occurred carbonic acid gas was
evolved, and, if the conditions were right (as the mediums say), the
fire was put out. It worked very nicely at experimental fires built
for the purpose, but was apt to fail in case of an involuntary
conflagration. About the year 1867 a patent was granted to Carlier
and Vignon, of France, for an apparatus in which water saturated with
carbonic acid gas was projected upon the fire by the expansive force of
the gas itself. As the apparatus was portable and the stream could be
directed to any point, it was obviously the desideratum needed. Mr. D.
Miles, of Boston, purchased the American patent, and subsequently sold
the territory, exclusive of New England, to the Babcock Co., who, at the
time, had a crude apparatus of their own. The first machines sold under
the new patent were filled with water and loaded with cartridges of dry
acid and bicarbonate of soda--the cap screwed down hastily, and, as the
chemicals dissolved, the gas was generated, the pressure raised, and
the water charged by absorption. The pressure of some 80 pounds was
sufficient to project a stream 50 feet or more, and the machine was set
upon the shelf so as to be ready for any fire that might occur. In many
cases, however, the pressure escaped after a short time, and the machine
when needed was found to be useless.
The most important step in the evolution of the modern extinguisher was
the adoption of a device for mixing liquid acid with the soda solution,
by the turning of a handle or screw, _after_ the alarm was given. This
was a practical machine, and proved of such value that an immense
business was built up. The result of this prosperity was the development
of new companies with new devices for accomplishing the same result,
which were successfully offered to the public with varying success.
As these were direct infringements upon the patent rights acquired by
the Babcock Company, their encroachments were resisted in the courts,
and much money was spent in the effort of the company to sustain their
rights, including the purchase of the patents of several rival machines
that possessed real merit or whose business was worth controlling.
Among these purchases was the right and good will of the "National"
Extinguisher Co., who used an acid cartridge of glass, the acid being
liberated by breaking the glass. This feature, united with important
improvements in general construction and the use of a peculiar glass
bottle instead of a tube, is the Babcock machine of to-day, the
combination making the simplest and most effective and reliable
apparatus ever built. In the meantime, an investigation before the
courts brought out the fact that the French patent was antedated by an
American invention, for which a patent was applied by a Dr. Graham, in
1837. and which possessed the essential features of the principle in
dispute. Graham, through lack of means, or for some other reason, had
failed to perfect his papers up to the time of his death, and, as the
invention was one of obvious importance, a bill was passed through
Congress for the reopening of the case, and the patent was issued to the
Graham heirs in 1878. Soon after the issue of the Graham patent, several
extinguisher firms, viz, Charles T. Holloway, of Baltimore; W. K.
Platt, of Philadelphia; S.F. Hayward of New York; the Protection Fire
Annihilator Co., of New York; the Babcock Manufacturing Co., of Chicago,
and the New England Fire Extinguisher Co., of Northampton, Mass., were
licensed to manufacture under the patent, by Archibald Graham, as
administrator of the estate of his father, who bound himself in these
licenses to issue no other licenses except with the approval of all
those who were included in the combination. This arrangement left
several enterprising manufacturers out in the cold, and one of these,
in investigating the status of extinguisher patents at Washington,
discovered an assignment of a quarter interest of the Graham patent to
a Mr. Burton, who, at the time of Graham's second application for a
patent, had assisted him with $500. This assignment had long been
forgotten--Burton having died, and his heirs knowing nothing of its
existence. The widow of Burton was hunted up, an assignment was secured
for $30,000, and a consolidated fire extinguisher company was formed,
which became the owner of the one quarter interest in the patent.
This combination, known as the "Fire Extinguisher Manufacturing Co.,"
included the Protective Annihilator Co., of New York; the Northampton
Fire Extinguisher Co, of Northampton, Mass.; and the North American Fire
Annihilator Co., of Philadelphia. The combination bought out the Babcock
Co., who had already acquired the patents of the Champion Co., all the
patents of the Conellies, of Pittsburg, and of the Great American Co.,
of Louisville, as well as the licenses of S. F. Hayward and W. K. Platt.
This covers all the extinguisher patents in existence, except those of
Charles T. Holloway, of Baltimore.
The advantages of the chemical engine are well summed up in the
following statement:
The superiority of a chemical engine consists--
1st. In its simplicity. It dispenses with complex machinery, experienced
engineers, reservoirs, and steam. Carbonic acid gas is both the working
and extinguishing agent.
2d. In promptness. It is always ready. No steam to be raised, no fire to
be kindled, no hose to be laid, and no large company to be mustered. The
chemicals are kept in place, and the gas generated the instant wanted.
In half the cases the time thus saved is a building saved. Five minutes
at the right time are worth five hours a little later.
3d. In efficiency. Mere water inadequately applied feeds the fire, but
carbonic acid gas never. Bulk for bulk, it is forty times as effective
as water, the seventy gallons of the two smallest cylinders being equal
to twenty-eight hundred gallons of water. Besides, it uses the only
agent that will extinguish burning tar, oil, and other combustible
fluids and vapors. One cylinder can be recharged while the other is
working, thus keeping up a continuous stream.
4th. In convenience. Five or six men can draw it and manage it. Its
small dimensions require but small area, either for work or storage. One
hundred feet or more of its light, pliant hose can be carried on a man's
arm up any number of stairs inside a building, or, if fire forbids, up a
ladder outside.
5th. In saving from destruction by water what the fire has spared.
It smothers, but does not deluge; the modicum of water used to give
momentum to the gas is soon evaporated by the heat, doing little or no
damage to what is below. This feature of the engine is of incalculable
worth to housekeepers, merchants, and insurance companies.
6th. Economy. It costs only about half as much as a first class hand
engine, and about one-fourth as much as a steam engine, with their
necessary appendages, and the chemicals for each charge cost less than
two dollars.
* * * * *
HOW TO TOW A BOAT.
A correspondent of _Engineering News_ says: Those living on swift
streams, and using small boats, often have occasion to tow up stream. So
do surveyors, hunters campers, tourists, and others. One man can tow a
boat against a swift current where five could not row.
Where there are two persons, the usual method is for one to waste his
strength holding the boat off shore with a pole, while the other tows.
Where but one person, he finds towing almost impossible, and when bottom
too muddy for poling and current too swift for rowing, he makes sad
progress.
[Illustration]
The above cut shows how one man can easily tow alone. The light
regulating string, B, passes from the stern of the boat to one hand of
the person towing, T. The tow line, A, is attached a little in front of
the center of the boat. Hence when B is slackened the boat approaches
the shore, while a very slight pull on it turns the boat outward. The
person towing glances back "ever and anon" to observe the boat's line of
travel.
* * * * *
RAILWAYS OF EUROPE AND AMERICA.
The following table, which has been prepared by the French Ministry of
Public Works, gives the railway mileage of the various countries of
Europe and the United States up to the end of last year, with the number
of miles constructed in that year, and the population per mile:
Total Built in 1881 Population per Mile
Germany 21,313 331 2,154
Great Britain 18,157 164 1,939
France 17,134 895 2,170
Austria-Hungary 11,880 262 3,200
Italy 5,450 109 5,321
Spain 4,869 176 3,492
Sweden & Norway 4,616 273 1,408
Belgium 2,561 48 2,203
Switzerland 1,557 22 1,831
Holland 1,426 83 2,885
Denmark 1,053 25 1,919
Roumania 916 56 5,860
Turkey 866 - 2,891
Portugal 757 8 5,870
Greece 6 - 28,000
------- ----- ------
Total 107,306 2,455 3,168
United States 104,813 9,358 502
It appears from this that the United States mileage was only 2,493 less
than the total of all Europe, and at the present time it exceeds it, as
the former country has built about 6,000 miles this year, whereas Europe
has not exceeded 1,500. The difference in the number of persons per mile
in the two cases is also very great, Europe taking six times as many
persons to support a mile of railway as the States, and can only be
accounted for by the fact that American railways are constructed much
cheaper than the European ones.
* * * * *
BEFORE IT HAPPENED.
AT 9 A.M. on Wednesday, September 13, the correspondent of a press
agency dispatched a telegram to London with the intimation that the
great battle at Tel-el-Kebir was practically over. It may possibly
astonish not a few of our readers (says a writer in the _Echo_), to
learn that this message reached the metropolis between 7 and 8 o'clock
on the same morning; and, in fact, had an unbroken telegraphic wire
extended from Kassassin to London, Sir Garnet Wolseley's great victory
might have been known here at 6:52 A.M., or (seemingly) at a time when
the fight was raging and our success far from complete. Nay, had the
telegram been flashed straight to Washington in the United States, it
would have reached there something like 1 h. 44 m. after the local
midnight of September 12. Paradoxical as this sounds the explanation
of it is of the most simple possible character. The rate at which
electricity travels has been very variously estimated. Fizeau asserted
that its velocity in copper wire was 111,780 miles a second; Walker
that it only travels 18,400 miles through that medium during the same
interval; while the experiments made in the United States during the
determination of the longitudes of various stations there still further
reduced the rate of motion to some 16,000 miles a second. Whichever of
these values we adopt, however, we may take it for our present purpose,
that the transmission of a message by the electric telegraph is
practically instantaneous. But be it here noted, there is no such a
thing as a _hora mundi_ or common time for the whole world. What is
familiarly known as longitude is really the difference in time, east
or west, from a line passing through the north and south poles of
the earth; and the middle of the great transit circle is the Royal
Observatory at Greenwich. If in the latitude of London (51 deg. 30' N.),
we proceed 10 miles and 1,383 yards either in an easterly or westerly
direction, we find that the local time is respectively either one minute
faster or one minute slower than it was at our initial point. Let us
try to understand the reason of this. If we fix a tube rigidly at any
station on the earth's surface, pointing to that part of the sky in
which any bright star is situated when such star is due south (or, as it
is technically called, "on the meridian"), and note by a good clock the
hour, minute, and second at which it crosses a wire stretched vertically
across the tube, then after a lapse of 23 h. 56 m. 4.09 s., will that
star be again threaded on the wire. If the earth were stationary--or,
rather, if she had no motion but that round her axis--this would be the
length of our day. But, as is well known, she is revolving round the sun
from left to right; and, as a necessary consequence, the sun seems to be
revolving round her from right to left; so that if we suppose the sun
and our star to be both on the wire together to-day, to-morrow the sun
will appear to have traveled to the left of the star in the sky; and the
earth will have that piece more to turn upon her axis before our tube
comes up with him again. This apparent motion of the sun in the sky is
not an equable one. Sometimes it is faster, sometimes slower; sometimes
more slanting, sometimes more horizontal. Thus it comes to pass that
solar days, or the intervals elapsing between one return of the sun to
the meridian and another, are by no means equal. So a mean of their
lengths is taken by adding them up for a year, and dividing by 365;
and the quantity to be divided to or subtracted from the instant of
"apparent noon" (when the sun dial shows 12 o'clock), is set down in the
almanac under the heading of "The Equation of Time." We may, however,
here conceive that it is noon everywhere in the northern hemisphere when
the sun is due south. Now the earth turns on her axis from west to east,
and occupies 24 h. in doing so. As all circles are conceived to be
divided into 360 deg., it is obvious that in one hour 15 deg. must pass beneath
the sun or a star; 30 deg. in two hours, and so on. The longitude of
Kassassin is, roughly speaking, 32 deg. east, so that when the sun is due
south there, or it is noon, the earth must go on turning for two hours
and eight minutes before Greenwich comes under the sun, or it is noon
there, which is only another way of saying that at noon at Kassassin it
is 9 h. 52 m. A.M. at Greenwich. It is this purely local character
of time which gives rise to the seeming paradox of our being able to
receive news of an event before (by our clocks) it has happened at all.
* * * * *
THE ADER RELAY.
This new instrument has excited considerable interest among telegraph
and telephone men by its exceeding sensitiveness. It is so sensitive
to the passage of an electric current that a battery formed with an
ordinary pin for one electrode and a piece of zinc wire for the other,
immersed in a single drop of water, will give sufficient current
to operate the relay. In practice it has successfully worked as a
telephonic call on the Eastern Railroad Company's line between Nancy
and Paris, a distance of 212 miles, requiring but two cups of ordinary
Leclanche battery.
The instrument consists of two permanent horseshoe magnets, fixed
parallel with each other and an inch apart. A very thin spool or bobbin
of insulated wire is suspended, like the pendulum of a clock, between
these permanent magnets, in such a manner that the bobbin hangs just
in front of the four poles. A counterpoise is fixed at the top of the
pendulum bar, which permits the adjusting of the antagonistic forces
represented by the action of the swinging bobbin, and two springs, which
are insulated from the mass, and which form one electrode of the local
or annunciator circuit, while the pendulum bar forms the other.
It will be easily understood that as the bobbin hangs freely in the
center of a very strong magnetic field (formed by the four poles of the
two permanent magnets), the slightest current sent through the bobbin
will cause the bobbin to be attracted from one direction, while it will
be repelled from the other, according to the polarity of the current
transmitted.
As the relay has a very low resistance, it is evident that it will
become an acceptable auxiliary in our central office, particularly when
used as a "calling off" signal, as by its use the ground deviation, so
objectionable and yet so universally used for "calling off" purposes,
can be entirely avoided, and the relay left directly in the circuit, as
is being done here in Paris. R. G. BROWN.
Paris, September 12, 1882.
* * * * *
THE PLATINUM WATER PYROMETER.
By J. C. HOADLEY.
The following description of the apparatus used for the determination
of high temperatures, up nearly to the melting point of platinum, is
offered in answer to several inquiries on the subject:
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