Scientific American Supplement, No. 447, July 26, 1884

V >> Various >> Scientific American Supplement, No. 447, July 26, 1884

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The most important consequence, however, is the absence of any fixed
frame. In all machines, bicycles and tricycles, with the usual fixed
frame, a position is found for the saddle which is, on the whole, most
suitable. For some particular gradient it will be perfect; on a steeper
gradient the treadles will be further in advance, but with a steeper
gradient the rider should be more over the front of the treadles. To get
his weight further to the front, he has to double up in the middle, and
assume a position in which he cannot possibly work to advantage. The
swinging frame of the Otto carries the treadles, of necessity, further
back, so that the Ottoist, when working at his hardest, is still
upright, with his hands in the line between his shoulders, and his feet
and his arms straight, so that he can hold himself down, and employ his
strength in a perfectly natural position. On going down a slope, the
fixed frame of a bicycle or tricycle leans forward, and places the rider
in such a position that extra weight is thrown on his arms and his
shoulders, whereas the swing frame of the Otto goes back, and the rider
of necessity assumes that position in which his arms are relieved of all
strain. In so far as the general position taken by the automatic Otto
frame is concerned, nearly the same effect can be obtained by using the
swing frame of the Devon tricycle, which can be shifted and locked in
any position which the rider wishes, or by the sliding saddle, which can
be slid backward or forward and locked so as to place the rider in one
of three positions. Though the rider can by these devices assume nearly
that position with respect to the treadles which is most advantageous,
he cannot obtain that curious fore and aft oscillation made use of by
the Ottoist in climbing hills, which, as the model on the table shows,
enables him to get past the dead points without even moving, and which,
therefore, makes the Otto by far the best hill-climbing machine there
is, if account is taken of the high speeding with which all Ottoists
ride. This is a proposition which none who knows the machine will
question for one moment.

The freedom of motion resulting from the swing of the frame of the Otto
gives a pleasurable sensation, which those who have only experienced the
constrained motion of a three-wheeler cannot even understand.

The very peculiar method of driving and steering, which seems so
puzzling to the novice, especially if he is a good rider of other
machines--for in that case he is far worse off than one who has never
ridden anything--give the rider, when he is familiar with them, a
control over the machine which is still surprising to me. In the first
place, the machine will run along straight, backward or forward, so
long as the handles are let alone. This automatic straight running is a
luxury, for until a deviation has to be made, the steering handles need
not be touched, and the rider may, if sufficiently confident, travel
with his arms folded or his hands in his pockets. The rigid connection
between the cranks and the wheels does away with all the backlash,
which is so unpleasant with chain or toothed wheel gearing. There is no
differential gear or clutch, but the machine possesses the advantage
of the clutch over the differential gear when meeting with unequal
resistance on a straight course, for each wheel must travel at the same
speed; but, in turning a corner, instead of driving the inner wheel
only, which is done by the clutch or both wheels equally, which is the
case with differential gear, each wheel is driven, but the outer one
more than the inner. At high speeds, the steering of the Otto has this
advantage, that whereas, with a given action on a tricyle, the same
deviation will be effected in the same _space_ at high as at low speeds,
the same action on the Otto will, at high speeds, produce the same
deviation in the same _time_ as it does at low speeds; and so instead of
becoming more sensitive at high speeds, as is the case with the tricyle,
the steering of the Otto remains the same. This is because the steering
of the tricycle depends on a kinematical, that of the Otto on a
dynamical principle.

In another respect, no machine can approach the Otto; at almost any
speed the rider can, if there is reason, instantly dismount, by which
action he puts on the brakes, and the machine will save him from
falling, stopping with him almost instantly. As is well known, we can
move backward and forward, we can twist around and around in our own
width, or can ride over bricks with impunity.

One objection to the machine is the difficulty of learning, which is
considerable, but which presents no danger. This difficulty has been
much exaggerated, for before the present powerful brake was applied it
did require considerable skill to ride it down a steep hill. The way
to do this must still be learnt, but it is now comparatively easy. For
going down steep hills, the front steering tricycle is without a rival;
I do not know what other machine will do this better than the Otto.
Lastly, the foot straps, which would be a great advantage on any
machine, if only they were safe, are not--though none but riders will
believe it--in any way a source of danger on the Otto. Having ridden
this machine for close upon 10,000 miles, I can speak with more
authority on this point than can those who are not able to sit upon it
for a moment.

The only disadvantage which the machine presents is the fact that it is
impossible to remove the feet from the pedals while running, without
dismounting; but though they must at all times follow the pedals, the
Ottoist is not, as is generally thought, working when descending a hill.

The enthusiastic terms in which every one who has mastered the
peculiarities of the Otto speaks of it would be considered as evidence
in its favor, if we were not all considered by other cyclists to be in
various stages of lunacy.

* * * * *

THE CANAL IRON WORKS, LONDON.

Some interest is awakened in engineering circles in London, just now, by
the approaching close of the old engineering works so well known as the
"Canal Ironworks," at the entrance to the Isle of Dogs, London, E. This
notable establishment stands second in priority in London--that of
Messrs. Maudslay, Sons & Field being the oldest--for the manufacture of
marine engines. It was founded by the late Messrs. Seawards, above sixty
years ago. Here was originated Seaward's hoisting "sheers" with the
traveling back leg, a modern example of which, 100 feet high, in iron,
stands on the wharf. An interesting tool, also, is the large vertical
boring machine for largest size cylinders; Seaward spent L5,000 upon
this, and it is certainly an admirable tool. There is also the large
vertical slotting machine, with a stroke up to 5 feet 2 inches, a
wonderfully powerful and compact machine. The extensive collection of
screwing tackle is, perhaps, unsurpassed, and extends up to 8 inches
diameter. There is a peculiar erecting shop roof, which will still repay
examination.

* * * * *

MARINONI'S ROTARY PRINTING PRESS.

The greatest progress that has been made in recent years in the art
of printing is in the invention of the high speed press provided with
continuous paper.

Three French constructors, Messrs. Marinoni, Alauzet, and Derriey, have
brought this kind of apparatus to such a degree of perfection that
the majority of foreign journals having a large circulation buy their
presses in France. We reproduce in Fig. 1 a perspective view of the
Marinoni press, and in Fig. 2 a diagram showing the parts of the same.
In order to give a complete description of it, we cannot do better than
to reproduce the very interesting study that has been made of it by Mr.
Monet, a civil engineer.

[Illustration: FIG. 1.--MARINONI'S ROTARY PRINTING PRESS.]

The roller, J (Fig. 2), is placed in the machine in the state in which
it is received from the paper manufactory. The paper unwinds, runs over
the rollers, e and e', which serve only for tautening it, and then
passes between the two cylinders, A and B. The cylinder, A, carries the
form, and B carries the blanket, and the paper thus receives its first
impression. It afterward passes between the cylinders, A' and B', and
receives an impression on the other side, the cylinder, A', carrying the
form, and B' the blanket. Being now printed on both sides, it passes
between the cylinders, KK', which cut it off and allow the sheet to
slide between the cords of the rollers. These latter lead the sheets
over the rollers, g h, on which they wind, one over the other, when the
rollers, a a', are in the position shown by unbroken lines in the cut.

The part of the machine that holds the rollers, g h, and the different
cords that wind over them, is the _accumulator_, and it is in this part
of the press that the sheets accumulate, one over the other, to any
number desired.

The size of the rollers, g h, and their distance apart are so regulated
that when the sheet reaches the accumulator, it falls exactly on those
that have preceded it. When the proper number of sheets is in the
accumulator (4 or 5 being the number most employed for afterward
facilitating the separation into packets on the receiving table), the
two small rollers, a a', advance over the rack, N, and the sheets,
instead of continuing to roll over into the accumulator, fall on the
rack and are deposited by it upon the receiving table, O.

[Illustration: FIG. 2.--MARINONI'S PRESS.]

The rack having fallen twenty times, and deposited five sheets each
time, or one hundred in all, the table moves in such a way as to prevent
the sheets subsequently deposited from getting mixed with them. When the
rack has fallen twenty times, the table returns to its initial position.

The distributing rollers, D, come in contact with the inking rollers, I,
once during each revolution of the printing cylinders, and are mounted
on racking levers provided with regulating screws that permit of easily
regulating the amount of ink taken up. The supports of the inking
rollers are movable and can be made to approach or recede from the
distributing rollers, so as to still further vary the amount of ink
taken up by them.

The distributing rollers supply the ink to a roller, E, of large
diameter, which, having a backward and forward motion, begins to
distribute the ink and to transmit it to a second roller, F, of the same
diameter. This latter then spreads it over a metallic cylinder, G, which
is of the same diameter as the printing cylinders, and against which
revolve three distributing rollers, H, that have a backward and forward
motion.

Between the cylindrical inking table, G, and the type cylinder, there
are situated inking cylinders, T, of large diameter, that constantly
take up ink from the inking table and distribute it over the types.

The machine here described, when designed for printing large sized
journals, has cylinders whose circumference corresponds to the size of
paper for two widths of pages, and whose length is sufficient to allow
it to receive two forms. Each cylinder, then, carries four forms, or
eight in all, and prints two complete copies at each revolution.

The large sheet cut off by the cylinders, K K', contains, then, two
copies; and this sheet, on passing under the roller, f is again cut in
two by a disk which separates it in a direction perpendicular to the
cylinders.

To this press there may be added a mechanical folder of Mr. Marinoni's
invention, capable of folding a journal five times.--_Annales
Industrielles_.

* * * * *

CHENOT'S ECONOMIC FILTER PRESS.

Mr. E. Chenot, who is occupied in the manufacture of wine from dry
grapes, has been led to devise a new style of filter, which by reason of
its mode of action and its construction, he calls the "Economic Filter
Press."

The apparatus, which is shown in the accompanying cut, consists of flat
bags whose mouth may be at the top, as usual, or at the side. Through
this orifice there is introduced a flat piece of wood or metal, which,
like the bag, has an aperture through the center. The whole is suspended
from a distributing pipe that is fixed at one end to the frame and is
free at the other. This pipe is slotted beneath, and the pieces of wood
or metal contain, opposite the slot, a number of small apertures that
put the distributer in communication with the interior of the bags.
Between these latter there are placed wire cloth frames which hold them
in position and facilitate the flow of the filtered liquid. The cut
shows the filter provided with a portion of its bags and frames. When
all the frames are in place they are locked by causing the movable plate
to move forward by means of two screws connected with an endless chain
and actuated by a hand wheel. The pressure of this plate closes up the
bags hermetically. Then, the feed cock being opened, the liquid flows
into all the bags, deposits therein what it holds in suspension, and the
clarified product flows to the inclined bottom of the filter and from
thence to the exterior.

[Illustration: CHENOT'S ECONOMIC FILTER PRESS.]

The apparatus may be supplied either through an upper reservoir, a juice
elevator, or a pump. The discharge is proportional to the square root
of the pressure. When the bags are full of residuum, the feed cock is
closed, the filter is unscrewed, and the bags and frames are taken out.
With fresh bags and the same frames, it is possible to at once set the
apparatus in operation again.

Before the filter is taken apart, the residuum may be exhausted by
washing it either with water or steam, or by pressure. To effect the
operation by pressure, the pieces of wood or metal are removed, the
mouths are closed by making a fold in the top of the bags, and the
latter are then put back into the apparatus or into an ordinary press
and submitted to another squeezing.

To render the maneuvering of it easier, the apparatus has been given a
horizontal position.--_Revue Industrielle_.

* * * * *

[American Engineer]

STEEL CHAINS WITHOUT WELDING.

We take the following description, together with the illustrations, of
a method and machine for making steel chain without welding, from our
valued contemporary, _Le Genie Civil_, of Paris:

When we regard an ordinary oval-linked chain endwise, it presents itself
in the form of a metal cross, and it was this that gave the cue to M.
Oury, of the Government Arsenals, to construct chain without welding. By
a series of matrices and punches, etc., he contrives, with small loss of
metal, to model a chain out of cross-shaped steel bar.

Steel is the better material for such usage, from its homogeneity, both
as to composition and strength.

Referring to the plate below, Figs. 1 to 10 explain the successive steps
from the bar to the finished chain.

Fig. 1 shows in plan and section the steel bar, whose length may be some
40 feet, and which would make a chain say 50 feet long. The shape of the
bar presents no difficulties in the way of rolling.

Figs. 2 and 3 give, in side elevations of the two faces and sections,
the first rough form of the links. These first begin to take the
exterior shape with the rounding of the angles.

The operations following, represented by Figs. 4 and 5, is the piercing
of the center of the links, which can later be furnished with a stay for
such chains as require special strength. The point now is to detach the
links, which is accomplished by oblique piercings, as shown in Fig. 6.
In the operation represented by Fig. 7, the oval shape is imparted to
the link, and the operation finishes as shown in Fig. 8.

Actually, the links are circular and separate. This separation is
retarded as much as possible, for it is plain that it is easier
to operate a rigid bar than a chain, above all when the operation
necessitates its being pushed forward.

By means of a good system of heating, analogous to that employed on the
large parts entering into ship construction, it is hoped to perform a
major part of the operations, of which we have given but an idea, at a
single heat.

[Illustration: MACHINE FOR MAKING CHAIN WITHOUT WELDING.]

These operations require work on both faces alternately--this presents
no difficulties; but what appears to us most difficult to realize is
_continuous work_, the bar passing through several machines which
successively impress upon it the steps of progress toward the finished
chain. If the machines are end on to each other in a direct line, there
will necessarily be a fixed place for each tool; the rough cut chain
must accurately reach the point where another tool is ready to continue
the modeling. This appears to us practically impossible, the more so as
the elongation which the bar takes at each stamp varies with its initial
diameter.

What is more admissible is that with one heat and in the same machine an
operation could be performed on the two faces perpendicularly. The bar
could then be taken from one furnace and put in another immediately,
to pass at once to another machine to again undergo the operations
following. The work could then be done rapidly, submitting the bar to
several heats.

A few words on the tools as they exist.

The most important principle to note, and on which the different
machines employed are designed, is this: The punches or matrices acting
on the chain at its different points of progress are put in motion by
spiral springs worked by means of tappets or cams distributed over the
circumference of a cylinder, having a rotary movement imparted to it by
pulleys and belts.

The figures on our plate show with sufficient clearness the working of
one of these machines. It will be seen that the bar traverses through
and through the machine for stamping, and that it can be disengaged for
a reheating before passing to subsequent operations.

* * * * *

The bog peat of Mexico is now being used on a considerable scale as fuel
for locomotives, stationary engines, smelting purposes, smiths' fires,
and househould use. The peat is mixed with a proper proportion of
bitumen, and is said not only to burn freely, and without smoke in much
quantity, but to give a higher dynamic equivalent of heat than the same
amount of wood.

* * * * *

THE BITTER SUBSTANCE OF HOPS.

[Footnote: _The Brewers' Guardian_, from the _Zeit. f. d. gesammte
Brauwesen_.]

By DR. H. BUNGENER.

Little that is definite is known of the substance or substances to
which the hop owes its bitterness. Lermer has succeeded, it is true, in
separating from hops a crystallized colorless substance, insoluble in
water, an alkaline solution of which has a marked bitter flavor, and
which easily changes on exposure to the air, assuming a resinous form.
According to Lermer, the formula of this substance is C_{32}H_{50}O_{7};
it possesses the properties of a weak acid and forms a characteristic
copper salt, which is soluble in ether. This hop bitter is, however,
produced from the hop by a very roundabout process, by treatment of the
extract with alkalies; it is not therefore regarded by many as present
in this form in the hop, and they hold that it is only produced by
the action of the alkalies. On the other hand, however, Etti, by a
complicated extracting process, but without using an alkali, succeeded
in producing a bitter substance from hops, which is, however, soluble in
water.

Several experiments convinced me that there really existed in hops a
crystallizable substance, insoluble in water, the alcoholic and alkaline
solution of which had a bitter flavor, in short, which possessed all
the properties of Lermer's hop bitter acid. Petroleum ether is the best
practical solvent in use for its isolation, as it does not dissolve
the majority of the remaining constituents of the hop, especially the
hop-resin, which they contain in considerable quantity. Still, the
extraction of hop-bitter acid from hops is a troublesome and thankless
job, the petroleum ether taking up certain substances which add greatly
to the difficulty of purifying the crystals. On the other hand, we can
readily and quickly attain our object, if we employ for our original
material fresh lupuline from unsulphured hops.

The following process has furnished me the best results:

The lupuline is first freed from gross impurities (hop-seed leaves,
etc.), and then covered with petroleum ether boiling at a low
temperature (40 deg. to 70 deg.) in stoppered flasks. The mixture is shaken up
from time to time. After twenty-four hours, by means of a Zullowsky
filter immersed in the mass, and with the aid of a suction-pump, the
dark brown solution is drawn off; then fresh ether is poured on to the
lupuline, and it is allowed to stand for another twenty-four hours.
After this process has been three times repeated, nearly everything the
petroleum will dissolve has probably been extracted. The solutions are
put together, and the petroleum ether distilled off _in vacuo_ at a low
temperature, until there remains in the flask a dark brown sirup, which
on cooling solidifies into a crystalline mass. This is pulverized and
turned on to a filter composed of a large funnel, in which a smaller
funnel covered with muslin is inserted. With the aid of a suction-pump,
the greater portion of the thick, crude solution can be filtered
through. There remains on the filter a highly colored crystalline
"cake," which should be pulverized with a small quantity of petroleum
ether and again filtered. After this operation has been repeated three
or four times, we obtain an almost colorless mass, consisting of
hop-bitter acid, contaminated by small quantities of a fatty substance,
and a substance which I could not isolate, and which I had at first
great trouble in separating from the hop-bitter acid.

If we do not wish to utilize this crude substance at once, it will be
necessary to melt it in the water bath and pour it into a bottle under
close seal, where it will at once crystallize and solidify. If it
remains exposed to the atmosphere, it will soon become sticky and
turn partly into resin. Six kilos of lupuline, which included a large
proportion of sand, furnished 400 grammes of crude hop-bitter acid. The
first experiments in crystallization with petroleum ether gave poor
results; it is difficult to produce the acid pure in large quantities
by this process, as a small quantity of the above substance obstinately
clings to it, and it readily assumes a non-crystallizable form. Our
object is more readily attained if we crystallize it once from alcohol,
for which purpose we dissolve it in a little lukewarm alcohol, then
quickly cool the solution; flakes of a fatty substance will be
separated, which are removed by filtration with the aid of a
suction-pump. Then we throw a few small crystals of the acid into the
solution, and after a short time crystallization commences. As soon as
it appears to be ended, the mother solution is removed with the aid of a
platinum cone, and the crystals washed with a little cold alcohol. The
alcoholic mother solution, which still contains the chief part of the
bitter acid, must be quickly evaporated, and the residue consigned to
a flask. The acid crystallized from the alcohol is then recrystallized
several times from petroleum-ether. In order to quickly dissolve the
bitter substance, it should be carefully melted in a flask, and double
its volume of ether gradually added; on its cooling, we obtain beautiful
prismatic crystals, which attain a length of 1 cm., and become perfectly
pure after four or five crystallizations. The mother solutions must be
speedily evaporated if we still wish to obtain crystals; after a time
they will only furnish a resinous residue.

The hop-bitter acid melts at 92 deg. to 93 deg.. It is easily soluble in
alcohol, ether, benzol, chloroform, sulphide of carbon, and vinegar; to
a lesser extent in cold petroleum ether, and not at all in water.

In the analysis I obtained figures which correspond best with those
calculated from the formula C_{25}H_{35}O_{4}.

Obtained.
Calculated. ------------------------^-----------------------
-----^----- 2. Crystal. 3. Crystal. 5. Crystal. 6. Crystal.
p.c. p.c. p.c. p.c. p.c. p.c. p.c.
C 75.19 74.79 74.83 74.9 75.04 75.05 75.07
H 8.77 8.97 8.90 8.85 8.87 8.83 8.80
O 16.04

If we shake up the ether solution of bitter substance with an aqueous
solution of acetate of copper, the ether will assume a green color, and
gradually deposits a green crystalline powder, a cupreous combination
of the bitter acid. It is difficult to obtain in a pure state, as the
solutions are readily subject to slight decomposition, accompanied by a
small deposit of copper oxide. This combination is readily soluble in
alcohol, to a lesser extent in ether, and is insoluble in water.

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