Scientific American Supplement No. 360, November 25, 1882
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Various >> Scientific American Supplement No. 360, November 25, 1882
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[Illustration: FIG. 4]
The number of recorded experiments with fans is very small, and a great
deal of ignorance exists as to their true efficiency. Mr. Buckle is one
of the very few authorities on the subject. He gives the accompanying
table of proportions as the best for pressures of from 3 to 6 ounces per
square inch:
--------------------------------------------------------------
| Vanes. | Diameter of inlet
Diameter of fans. |------------------------| openings.
| Width. | Length. |
--------------------------------------------------------------
ft. in. | ft. in. | ft. in. | ft. in.
3 0 | 0 9 | 0 9 | 1 6
3 6 | 0 101/2 | 0 101/2 | 1 9
4 0 | 1 0 | 1 0 | 2 0
4 6 | 1 11/2 | 1 11/2 | 2 3
5 0 | 1 3 | 1 3 | 2 6
6 0 | 1 6 | 1 6 | 3 0
| | |
--------------------------------------------------------------
For higher pressures the blades should be longer and narrower, and
the inlet openings smaller. The case is to be made in the form of an
arithmetical spiral widening, the space between the case and the blades
radially from the origin to the opening for discharge, and the upper
edge of the opening should be level with the lower side of the sweep of
the fan blade, somewhat as shown in Fig. 5.
[Illustration: FIG. 5]
A considerable number of patents has been taken out for improvements
in the construction of fans, but they all, or nearly all, relate to
modifications in the form of the case and of the blades. So far,
however, as is known, it appears that, while these things do exert a
marked influence on the noise made by a fan, and modify in some degree
the efficiency of the machine, that this last depends very much more on
the proportions adopted than on the shapes--so long as easy curves
are used and sharp angles avoided. In the case of fans running at low
speeds, it matters very little whether the curves are present or not;
but at high speeds the case is different.--_The Engineer_.
* * * * *
MACHINE FOR COMPRESSING COAL REFUSE INTO FUEL.
The problem as to how the refuse of coal shall be utilized has been
solved in the manufacture from it of an agglomerated artificial
fuel, which is coming more and more into general use on railways and
steamboats, in the industries, and even in domestic heating.
The qualities that a good agglomerating machine should present are as
follows:
1. Very great simplicity, inasmuch as it is called upon to operate in
an atmosphere charged with coal dust, pitch, and steam; and, under such
conditions, it is important that it may be easily got at for cleaning,
and that the changing of its parts (which wear rapidly) may be effected
without, so to speak, interrupting its running.
2. The compression must be powerful, and, that the product may be
homogeneous, must operate progressively and not by shocks. It must
especially act as much as possible upon the entire surface of the
conglomerate, and this is something that most machines fail to do.
3. The removal from the mould must be effected easily, and not depend
upon a play of pistons or springs, which soon become foul, and the
operation of which is very irregular.
The operations embraced in the manufacture of this kind of fuel are as
follows:
The refuse is sifted in order to separate the dust from the grains of
coal. The dust is not submitted to a washing. The grains are classed
into two sizes, after removing the nut size, which is sold separately.
The grains of each size are washed separately. The washed grains are
either drained or dried by a hydro-extractor in order to free them from
the greater part of the water, the presence of this being an obstacle to
their perfect agglomeration. The water, however, should not be entirely
extracted because the combustibles being poor conductors of heat, a
certain amount of dampness must be preserved to obtain an equal division
of heat in the paste when the mixture is warmed.
After being dried the grains are mixed with the coal dust, and broken
coal pitch is added in the proportion of eight to ten per cent. of the
coal. The mixture is then thrown into a crushing machine, where it is
reduced to powder and intimately mixed. It then passes into a pug-mill
into which superheated steam is admitted, and by this means is converted
into a plastic paste. This paste is then led into an agitator for the
double purpose of freeing it from the steam that it contains, and of
distributing it in the moulds of the compressing machine.
[Illustration: IMPROVED MACHINE FOR COMPRESSING REFUSE COAL INTO FUEL.]
Bilan's machine, shown in the accompanying cut, is designed for
manufacturing spherical conglomerates for domestic purposes. It consists
of a cast iron frame supporting four vertical moulding wheels placed at
right angles to each other and tangent to the line of the centers. These
wheels carry on their periphery cavities that have the form of a quarter
of a sphere. They thus form at the point of contact a complete sphere
in which the material is inclosed. The paste is thrown by shovel, or
emptied by buckets and chain, into the hopper fixed at the upper part
of the frame. From here it is taken up by two helices, mounted on a
vertical shaft traversing the hopper, and forced toward the point where
the four moulding wheels meet. The driving pulley of the machine is
keyed upon a horizontal shaft which is provided with two endless screws
that actuate two gear-wheels, and these latter set in motion the four
moulding wheels by means of beveled pinions. The four moulding wheels
being accurately adjusted so that their cavities meet each other at
every revolution, carry along the paste furnished them by the hopper,
compress it powerfully on the four quarters, and, separating by a
further revolution, allow the finished ball to drop out.
The external crown of the wheels carrying the moulds consists of four
segments, which may be taken apart at will to be replaced by others when
worn.
This machine produces about 40 tons per day of this globular artificial
fuel.--_Annales Industrielles_.
* * * * *
HANK SIZING AND WRINGING MACHINE.
We give a view of a hank sizing machine by Messrs. Heywood & Spencer,
of Radcliffe, near Manchester. The machine is also suitable for fancy
dyeing. It is well known, says the _Textile Manufacturer_, that when
hanks are wrung by hand, not only is the labor very severe, but in
dyeing it is scarcely possible to obtain even colors, and, furthermore,
the production is limited by the capabilities of the man. The machine
we illustrate is intended to perform the heavy part of the work with
greater expedition and with more certainty than could be relied upon
with hand labor. The illustration represents the machine that we
inspected. Its construction seems of the simplest character. It consists
of two vats, between which is placed the gearing for driving the hooks.
The large wheel in this gear, although it always runs in one direction,
contains internal segments, which fall into gear alternately with
pinions on the shanks of the hooks. The motion is a simple one, and it
appeared to us to be perfectly reliable, and not liable to get out of
order. The action is as follows: The attendant lifts the hank out of the
vat and places it on the hooks. The hook connected to the gearing then
commences to turn; it puts in two, two and a half, three, or more twists
into the hank and remains stationary for a few seconds to allow an
interval for the sizer to "wipe off" the excess of size, that is, to
run his hand along the twisted hank. This done, the hook commences to
revolve the reverse way, until the twists are taken out of the hank.
It is then removed, either by lifting off by hand or by the apparatus
shown, attached to the right hand side. This arrangement consists of a
lattice, carrying two arms that, at the proper moment, lift the hank off
the hooks on to the lattice proper, by which it is carried away, and
dropped upon a barrow to be taken to the drying stove. In sizing, a
double operation is customary; the first is called running, and the
second, finishing. In the machine shown, running is carried on one side
simultaneously with finishing in the other, or, if required, running
may be carried on on both sides. If desired, the lifting off motion is
attached to both running and finishing sides, and also the roller partly
seen on the left hand for running the hanks through the size. The
machine we saw was doing about 600 bundles per day at running and at
finishing, but the makers claim the production with a double machine to
be at the rate of about 36 10 lb. bundles per hour (at finishing), wrung
in 11/2 lb. wringers (or I1/2 lb. of yarn at a time), or at running at the
rate of 45 bundles in 2 lb. wringers. The distance between the hooks
is easily adjusted to the length or size of hanks, and altogether the
machine seems one that is worth the attention of the trade.
[Illustration: IMPROVED HANK SIZING MACHINE.]
* * * * *
IMPROVED COKE BREAKER.
The working parts of the breaker now in use by the South Metropolitan
Gas Company consist essentially of a drum provided with cutting edges
projecting from it, which break up the coke against a fixed grid. The
drum is cast in rings, to facilitate repairs when necessary, and the
capacity of the machine can therefore be increased or diminished by
varying the number of these rings. The degree of fineness of the coke
when broken is determined by the regulated distance of the grid from the
drum. Thus there is only one revolving member, no toothed gearing being
required. Consequently the machine works with little power; the one at
the Old Kent Road, which is of the full size for large works, being
actually driven by a one horse power "Otto" gas-engine. Under these
conditions, at a recent trial, two tons of coke were broken in half an
hour, and the material delivered screened into the three classes of
coke, clean breeze (worth as much as the larger coke), and dust, which
at these works is used to mix with lime in the purifiers. The special
advantage of the machine, besides the low power required to drive it and
its simple action, lies in the small quantity of waste. On the occasion
of the trial in question, the dust obtained from two tons of coke
measured only 31/2 bushels, or just over a half hundredweight per ton.
The following statement, prepared from the actual working of the first
machine constructed, shows the practical results of its use. It should
be premised that the machine is assumed to be regularly employed and
driven by the full power for which it is designed, when it will easily
break 8 tons of coke per hour, or 80 tons per working day:
500 feet of gas consumed by a 2 horse power
gas-engine, at cost price of gas delivered s. d.
in holder. 0 9
Oil and cotton waste. 0 6
Two men supplying machine with large
coke, and shoveling up broken, at 4s.
6d. 9 0
Interest and wear and tear (say). 0 3
-----
Total per day. 10 6
-----
For 80 tons per day, broken at the rate
of. 0 11/2
Add for loss by dust and waste, 1 cwt.,
with price of coke at (say) 13s. 4d. per
ton. 0 8
-----
Cost of breaking, per ton. 0 91/2
As coke, when broken, will usually fetch from 2s. to 2s. 6d. per ton
more than large, the result of using these machines is a net gain of
from 1s. 3d. to 1s. 9d. per ton of coke. It is not so much the actual
gain, however, that operates in favor of providing a supply of broken
coke, as the certainty that by so doing a market is obtained that would
not otherwise be available.
[Illustration: IMPROVED COKE BREAKER.]
It will not be overstating the case to say that this coke breaker is by
far the simplest, strongest, and most economical appliance of its kind
now manufactured. That it does its work well is proved by experience;
and the advantages of its construction are immediately apparent upon
comparison of its simple drum and single spindle with the flying hammers
or rocking jaws, or double drums with toothed gearing which characterize
some other patterns of the same class of plant. It should be remarked,
as already indicated, lest exception should be taken to the size of the
machine chosen here for illustration, that it can be made of any size
down to hand power. On the whole, however, as a few tons of broken coke
might be required at short notice even in a moderate sized works, it
would scarcely be advisable to depend upon too small a machine; since
the regular supply of the fuel thus improved may be trusted in a short
time to increase the demand.
[Illustration: IMPROVED COKE BREAKER.]
* * * * *
IMPROVEMENT IN PRINTING MACHINERY.
This is the design of Alfred Godfrey, of Clapton. According to this
improvement, as represented at Figs. 1 and 2, a rack, A, is employed
vibrating on the pivot a, and a pinion, a1, so arranged that instead of
the pinion moving on a universal joint, or the rack moving in a parallel
line from side to side of the pinion at the time the motion of the table
is reversed, there is employed, for example, the radial arm, a2, mounted
on the shaft, a3, supporting the driving wheel, a4. The opposite or
vibrating end of the radial arm, a2, supports in suitable bearings the
pinion, a1, and wheel, a5, driving the rack through the medium of the
driving wheel, a4, the effect of which is that through the mechanical
action of the vibrating arm, a2, and pinion, a1 in conjunction with the
vibrating movement of the rack, A, an easy, uniform, and silent motion
is transmitted to the rack and table.
[Illustration: IMPROVEMENTS IN PRINTING MACHINERY. Fig. 1]
[Illustration: IMPROVEMENTS IN PRINTING MACHINERY. Fig. 2.]
* * * * *
A CHARACTERISTIC MINING "RUSH."--THE PROSPECTIVE MINING CENTER OF
SOUTHERN NEW MEXICO.
A correspondent of the _Tribune_ describes at length the mining camps
about Lake Valley, New Mexico, hitherto thought likely to be the central
camp of that region, and then graphically tells the story of the recent
"rush" to the Perche district. Within a month of the first strike of
silver ore the country was swarming with prospectors, and a thousand or
more prospects had been located.
The Perche district is on the eastern flanks of the Mimbres Mountains,
a range which is a part of the Rocky Mountain range, and runs north and
south generally parallel with the Rio Grande, from which it lies about
forty miles to the westward. The northern half of these mountains is
known as the Black Range, and was the center of considerable mining
excitement a year and a half ago. It is there that the Ivanhoe is
located, of which Colonel Gillette was manager, and in which Robert
Ingersoll and Senator Plumb, of Kansas, were interested, much to the
disadvantage of the former. A new company has been organized, however,
with Colonel Ingersoll as president, and the reopening of work on the
Ivanhoe will probably prove a stimulus to the whole Black Range. From
this region the Perche district is from forty to sixty miles south. It
is about twenty-five miles northwest of Lake Valley, and ten miles west
of Hillsboro, a promising little mining town, with some mills and about
300 people. The Perche River has three forks coming down from the
mountains and uniting at Hillsboro, and it is in the region between
these forks that the recent strikes have been made.
On August 15 "Jack" Shedd, the original discoverer of the Robinson mine
in Colorado, was prospecting on the south branch of the north fork of
the Perche River, when he made the first great strike in the district.
On the summit of a heavily timbered ridge he found some small pieces of
native silver, and then a lump of ore containing very pure silver in the
form of sulphides, weighing 150 pounds, and afterward proved to be worth
on the average $11 a pound. All this was mere float, simply lying on the
surface of the ground. Afterward another block was found, weighing 87
pounds, of horn silver, with specimens nearly 75 per cent. silver. The
strike was kept a secret for a few days. Said a mining man: "I went up
to help bring the big lump down. We took it by a camp of prospectors who
were lying about entirely ignorant of any find. When they saw it they
instantly saddled their horses, galloped off, and I believe they
prospected all night." A like excitement was created when the news of
this and one or two similar finds reached Lake Valley. Next morning
every waiter was gone from the little hotel, and a dozen men had left
the Sierra mines, to try their fortunes at prospecting.
As the news spread men poured into the Perche district from no one knows
where, some armed with only a piece of salt pork, a little meal, and a
prospecting pick; some mounted on mules, others on foot; old men and men
half-crippled were among the number, but all bitten by the monomania
which possesses every prospector. Now there are probably 2,000 men in
the Perche district, and the number of prospects located must far exceed
1,000. Three miners from there with whom I was talking recently owned
forty-seven mines among them, and while one acknowledged that hardly one
prospect in a hundred turns out a prize, the other millionaire in embryo
remarked that he wouldn't take $50,000 for one of his mines. So it goes,
and the victims of the mining fever here seem as deaf to reason as the
buyers of mining stock in New York. Fuel was added to the flame by
the report that Shedd had sold his location, named the Solitaire, to
ex-Governor Tabor and Mr. Wurtzbach on August 25 for $100,000. This was
not true. I met Governor Tabor's representative, who came down recently
to examine the properties, and learned that the Governor had not up to
that date bought the mine. He undoubtedly bonded it, however, and his
representative's opinion of the properties seemed highly favorable.
The Solitaire showed what appeared to be a contact vein, with walls of
porphyry and limestone in a ledge thirty feet wide in places, containing
a high assay of horned silver. The vein was composed of quartz, bearing
sulphides, with horn silver plainly visible, giving an average assay of
from $350 to $500. This was free milling. These were the results shown
simply by surface explorations, which were certainly exceedingly
promising. Recently it has been stated that a little development shows
the vein to be only a blind lead, but the statement lacks confirmation.
In any case the effect of so sensational a discovery is the same in
creating an intense excitement and attracting swarms of prospectors.
But the Perche district does not rest on the Solitaire, for there has
been abundance of mineral wealth discovered throughout its extent. Four
miles south of this prospect, on the middle fork of the Perche, is an
actual mine--the Bullion--which was purchased by four or five Western
mining men for $10,000, and yielded $11,000 in twenty days. The ore
contains horn and native silver. On the same fork are the Iron King and
Andy Johnson, both recently discovered and promising properties, and
there is a valuable mine now in litigation on the south fork of the
Perche, with scores of prospects over the entire district. Now that one
or two sensational strikes have attracted attention, and capital is
developing paying mines, the future of the Perche District seems
assured.
* * * * *
THE SOY BEAN.
The _British Medical Journal_ says that Prof. E. Kinch, writing in the
_Agricultural Students' Gazette_, says that the Soy bean approaches more
nearly to animal food than any other known vegetable production, being
singularly rich in fat and in albuminoids. It is largely used as
an article of food in China and Japan. Efforts have been made to
acclimatize it in various parts of the continent of Europe, and fair
success has been achieved in Italy and France; many foods are made from
it and its straw is a useful fodder.
* * * * *
ON A NEW ARC ELECTRIC LAMP.
[Footnote: Paper read at the British Association, Southampton. Revised
by the Author.--_Nature_.]
By W.H. PREECE.
Electric lamps on the arc principle are almost as numerous as the trees
in the forest, and it is somewhat fresh to come upon something that is
novel. In these lamps the carbons are consumed as the current flows, and
it is the variation in their consumption which occasions the flickering
and irregularity of the light that is so irritating to the eyes. Special
mechanical contrivances or regulators have to be used to compensate for
this destruction of the carbons, as in the Siemens and Brush type, or
else refractory materials have to be combined with the carbons, as in
the Jablochkoff candle and in the lamp Soleil. The steadiness of the
light depends upon the regularity with which the carbons are moved
toward each other as they are consumed, so as to maintain the electric
resistance between them a constant quantity. Each lamp must have a
certain elasticity of regulation of its own, to prevent irregularities
from the variable material of carbon used, and from variations in the
current itself and in the machinery.
In all electric lamps, except the Brockie, the regulator is in the lamp
itself. In the Brockie system the regulation is automatic, and is made
at certain rapid intervals by the motor engine. This causes a periodic
blinking that is detrimental to this lamp for internal illumination.
[Illustration: FIG. 1. FIG. 2.]
M. Abdank, the inventor of the system which I have the pleasure of
bringing before the Section, separates his regulator from his lamp.
The regulator may be fixed anywhere, within easy inspection and
manipulation, and away from any disturbing influence in the lamp. The
lamp can be fixed in any inaccessible place.
_The Lamp_ (Figs. 1, 2, and 3.)--The bottom or negative carbon is fixed,
but the top or positive carbon is movable, in a vertical line. It is
screwed at the point, C, to a brass rod, T (Fig. 2), which moves freely
inside the tubular iron core of an electromagnet, K. This rod is
clutched and lifted by the soft iron armature, A B, when a current
passes through the coil, M M. The mass of the iron in the armature is
distributed so that the greater portion is at one end, B, much nearer
the pole than the other end. Hence this portion is attracted first, the
armature assumes an inclined position, maintained by a brass button, t,
which prevents any adhesion between the armature and the core of the
electromagnet. The electric connection between the carbon and the coil
of the electromagnet is maintained by the flexible wire, S.
[Illustration: FIG. 3.]
The electromagnet, A (Fig. 1), is fixed to a long and heavy rack, C,
which falls by its own weight and by the weight of the electromagnet and
the carbon fixed to it. The length of the rack is equal to the length of
the two carbons. The fall of the rack is controlled by a friction break,
B (Fig. 3), which acts upon the last of a train of three wheels put
in motion by the above weight. The break, B, is fixed at one end of
a lever, B A, the other end carrying a soft iron armature, F,
easily adjusted by three screws. This armature is attracted by the
electromagnet, E E (whose resistance is 1,200 ohms), whenever a current
circulates through it. The length of the play is regulated by the screw,
V. The spring, L, applies tension to the break.
_The Regulator_.--This consists of a balance and a cut-off.
_The Balance_ (Figs. 4 and 5) is made with two solenoids. S and S',
whose relative resistances is adjustable. S conveys the main current,
and is wound with thick wire having practically no resistance, and S'
is traversed by a shunt current, and is wound with fine wire having a
resistance of 600 ohms. In the axes of these two coils a small and light
iron tube (2 mm. diameter and 60 mm. length) freely moves in a vertical
line between two guides. When magnetized it has one pole in the middle
and the other at each end. The upward motion is controlled by the
spring, N T. The spring rests upon the screw, H, with which it makes
contact by platinum electrodes. This contact is broken whenever the
little iron rod strikes the spring, N T.
The positive lead from the dynamo is attached to the terminal, B, then
passes through the coil, S, to the terminal, B', whence it proceeds to
the lamp. The negative lead is attached to terminal, A, passing directly
to the other terminal, A', and thence to the lamp.
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