Scientific American Supplement, No. 460, October 25, 1884 by Various

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[Illustration]

SCIENTIFIC AMERICAN SUPPLEMENT NO. 460

NEW YORK, OCTOBER 25, 1884

Scientific American Supplement. Vol. XVIII, No. 460.

Scientific American established 1845

Scientific American Supplement, $5 a year.

Scientific American and Supplement, $7 a year.

* * * * *

TABLE OF CONTENTS.

I. CHEMISTRY. ETC.--Wolpert's Method of Estimating the
Amount of Carbonic Acid in the Air.--7 Figures.

Japanese Camphor.--Its preparation, experiments, and analysis
of the camphor oil.--By H. OISHI.

II. ENGINEERING AND MECHANICS.--Links in the History of the
Locomotive.--With two engravings of the Rocket.

The Flow of Water through Turbines and Screw Propellers.--By
ARTHUR RIGG.--Experimental researches.--Impact on level
plate.--Impact and reaction in confined channels.--4 figures.

Improved Textile Machinery.--The Textile Exhibition at
Islington.--5 figures.

Endless Rope Haulage.--2 figures.

III. TECHNOLOGY.--A Reliable Water Filter.--With engraving.

Simple Devices for Distilling Water.--4 figures.

Improved Fire Damp Detecter.--With full description and engraving.

Camera Attachment for Paper Photo Negatives.--2 figures.

Instantaneous Photo Shutter.--1 figure.

Sulphurous Acid.--Easy method of preparation for photographic
purposes.

IV. PHYSICS. ELECTRICITY, ETC.--Steps toward a Kinetic
Theory of Matter.--Address by Sir Wm. THOMSON at the Montreal
meeting of the British Association.

Application of Electricity to Tramways.--By M. HOLROYD
SMITH.--7 figures.

The Sunshine Recorder.--1 figure.

V. ARCHITECTURE AND ART.--The National Monument at Rome.--With
full page engraving.

On the Evolution of Forms of Art.--From a paper by Prof.
JACOBSTHAL.--Plant Forms the archetypes of cashmere
patterns.--Ornamental representations of plants of two
kinds.--Architectural forms of different ages.--20 figures.

VI. NATURAL HISTORY.--The Latest Knowledge about Gapes.--How
to keep poultry free from them.

The Voyage of the Vettor Pisani.--Shark fishing In the Gulf
of Panama.--Capture of Rhinodon typicus, the largest fish in
existence.

VII. HORTICULTURE, ETC.--The Proper Time for Cutting Timber.

Raising Ferns from Spores.--1 figure.

The Life History of Vaucheria.--Growth of alga vaucheria
under the microscope.--4 figures.

VIII. MISCELLANEOUS.--Fires in London and New York.

The Greely Arctic Expedition.--With engraving.

The Nile Expedition.--1 figure.

* * * * *

LINKS IN THE HISTORY OF THE LOCOMOTIVE.

It is, perhaps, more difficult to write accurate history than anything
else, and this is true not only of nations, kings, politicians, or wars,
but of events and things witnessed or called into existence in every-day
life. In _The Engineer_ for September 17, 1880, we did our best to place a
true statement of the facts concerning the Rocket before our readers. In
many respects this was the most remarkable steam engine ever built, and
about it there ought to be no difficulty, one would imagine, in arriving at
the truth. It was for a considerable period the cynosure of all eyes.
Engineers all over the world were interested in its performance. Drawings
were made of it; accounts were written of it, descriptions of it abounded.
Little more than half a century has elapsed since it startled the world by
its performance at Rainhill, and yet it is not too much to say that the
truth--the whole truth, that is to say--can never now be written. We are,
however, able to put some facts before our readers now which have never
before been published, which are sufficiently startling, and while
supplying a missing link in the history of the locomotive, go far to show
that much that has hitherto been held to be true is not true at all.

When the Liverpool and Manchester Railway was opened on the 15th of
September, 1830, among those present was James Nasmyth, subsequently the
inventor of the steam hammer. Mr. Nasmyth was a good freehand draughtsman,
and he sketched the Rocket as it stood on the line. The sketch is still in
existence. Mr. Nasmyth has placed this sketch at our disposal, thus earning
the gratitude of our readers, and we have reproduced as nearly as possible,
but to a somewhat enlarged scale, this invaluable link in the history of
the locomotive. Mr. Nasmyth writes concerning it, July 26, 1884: "This
slight and hasty sketch of the Rocket was made the day before the opening
of the Manchester and Liverpool Railway, September 12, 1830. I availed
myself of the opportunity of a short pause in the experimental runs with
the Rocket, of three or four miles between Liverpool and Rainhill, George
Stephenson acting as engine driver and his son Robert as stoker. The
limited time I had for making my sketch prevented me from making a more
elaborate one, but such as it is, all the important and characteristic
details are given; but the pencil lines, after the lapse of fifty-four
years, have become somewhat indistinct." The pencil drawing, more than
fifty years old, has become so faint that its reproduction has become a
difficult task. Enough remains, however, to show very clearly what manner
of engine this Rocket was. For the sake of comparison we reproduce an
engraving of the Rocket of 1829. A glance will show that an astonishing
transformation had taken place in the eleven months which had elapsed
between the Rainhill trials and the opening of the Liverpool and Manchester
Railway. We may indicate a few of the alterations. In 1829 the cylinders
were set at a steep angle; in 1830 they were nearly horizontal. In 1829 the
driving wheels were of wood; in 1830 they were of cast iron. In 1829 there
was no smoke-box proper, and a towering chimney; in 1830 there was a
smoke-box and a comparatively short chimney. In 1829 a cask and a truck
constituted the tender; in 1830 there was a neatly designed tender, not
very different in style from that still in use on the Great Western broad
gauge. All these things may perhaps be termed concomitants, or changes in
detail. But there is a radical difference yet to be considered. In 1829 the
fire-box was a kind of separate chamber tacked on to the back of the barrel
of the boiler, and communicating with it by three tubes; one on each side
united the water spaces, and one at the top the steam spaces. In 1830 all
this had disappeared, and we find in Mr. Nasmyth's sketch a regular
fire-box, such as is used to this moment. In one word, the Rocket of 1829
is different from the Rocket of 1830 in almost every conceivable respect;
and we are driven perforce to the conclusion that the Rocket of 1829
_never worked at all on the Liverpool and Manchester Railway; the engine of
1830 was an entirely new engine_. We see no possible way of escaping from
this conclusion. The most that can be said against it is that the engine
underwent many alterations. The alterations must, however, have been so
numerous that they were tantamount to the construction of a new engine. It
is difficult, indeed, to see what part of the old engine could exist in the
new one; some plates of the boiler shell might, perhaps, have been
retained, but we doubt it. It may, perhaps, disturb some hitherto well
rooted beliefs to say so, but it seems to us indisputable that the Rocket
of 1829 and 1830 were totally different engines.

[Illustration: FIG. 1. THE ROCKET, 1829. THE ROCKET, 1830.]

Our engraving, Fig. 1, is copied from a drawing made by Mr. Phipps,
M.I.C.E., who was employed by Messrs. Stephenson to compile a drawing of
the Rocket from such drawings and documents as could be found. This
gentleman had made the original drawings of the Rocket of 1829, under
Messrs. G. & R. Stephenson's direction. Mr. Phipps is quite silent about
the history of the engine during the eleven months between the Rainhill
trials and the opening of the railway. In this respect he is like every one
else. This period is a perfect blank. It is assumed that from Rainhill the
engine went back to Messrs. Stephenson's works; but there is nothing on the
subject in print, so far as we are aware. Mr. G.R. Stephenson lent us in
1880 a working model of the Rocket. An engraving of this will be found in
_The Engineer_ for September 17, 1880. The difference between it and the
engraving below, prepared from Mr. Phipps' drawing, is, it will be seen,
very small--one of proportions more than anything else. Mr. Stephenson says
of his model: "I can say that it is a very fair representation of what the
engine was before she was altered." Hitherto it has always been taken for
granted that the alteration consisted mainly in reducing the angle at which
the cylinders were set. The Nasmyth drawing alters the whole aspect of the
question, and we are now left to speculate as to what became of the
original Rocket. We are told that after "it" left the railway it was
employed by Lord Dundonald to supply steam to a rotary engine; then it
propelled a steamboat; next it drove small machinery in a shop in
Manchester; then it was employed in a brickyard; eventually it was
purchased as a curiosity by Mr. Thomson, of Kirkhouse, near Carlisle, who
sent it to Messrs. Stephenson to take care of. With them it remained for
years. Then Messrs. Stephenson put it into something like its original
shape, and it went to South Kensington Museum, where "it" is now. The
question is, What engine is this? Was it the Rocket of 1829 or the Rocket
of 1830, or neither? It could not be the last, as will be understood from
Mr. Nasmyth's drawing; if we bear in mind that the so-called fire-box on
the South Kensington engine is only a sham made of thin sheet iron without
water space, while the fire-box shown in Mr. Nasmyth's engine is an
integral part of the whole, which could not have been cut off. That is to
say, Messrs. Stephenson, in getting the engine put in order for the Patent
Office Museum, certainly did not cut off the fire-box shown in Mr.
Nasmyth's sketch, and replace it with the sham box now on the boiler. If
our readers will turn to our impression for the 30th of June, 1876, they
will find a very accurate engraving of the South Kensington engine, which
they can compare with Mr. Nasmyth's sketch, and not fail to perceive that
the differences are radical.

In "Wood on Railroads," second edition, 1832, page 377, we are told that
"after those experiments"--the Rainhill trials--"were concluded, the
Novelty underwent considerable alterations;" and on page 399, "Mr.
Stephenson had also improved the working of the Rocket engine, and by
applying the steam more powerfully in the chimney to increase the draught,
was enabled to raise a much greater quantity of steam than before." Nothing
is said as to where the new experiments took place, nor their precise date.
But it seems that the Meteor and the Arrow--Stephenson engines--were tried
at the same time; and this is really the only hint Wood gives as to what
was done to the Rocket between the 6th of October, 1829, and the 15th of
September, 1830.

There are men still alive who no doubt could clear up the question at
issue, and it is much to be hoped that they will do so. As the matter now
stands, it will be seen that we do not so much question that the Rocket in
South Kensington Museum is, in part perhaps, the original Rocket of
Rainhill celebrity, as that it ever ran in regular service on the Liverpool
and Manchester Railway. Yet, if not, then we may ask, what became of the
Rocket of 1830? It is not at all improbable that the first Rocket was cast
on one side, until it was bought by Lord Dundonald, and that its history is
set out with fair accuracy above. But the Rocket of the Manchester and
Liverpool Railway is hardly less worthy of attention than its immediate
predecessor, and concerning it information is needed. Any scrap of
information, however apparently trifling, that can be thrown on this
subject by our readers will be highly valued, and given an appropriate
place in our pages.--_The Engineer_.

* * * * *

The largest grain elevator in the world, says the _Nashville American_, is
that just constructed at Newport News under the auspices of the Chesapeake
& Ohio Railway Co. It is 90 ft. wide, 386 ft. long, and about 164 ft. high,
with engine and boiler rooms 40 x 100 ft. and 40 ft. high. In its
construction there were used about 3,000 piles, 100,000 ft. of white-oak
timber, 82,000 cu. ft. of stone, 800,000 brick, 6,000,000 ft. of pine and
spruce lumber, 4,500 kegs of nails, 6 large boilers, 2 large engines, 200
tons of machinery, 20 large hopper-scales, and 17,200 ft. of rubber belts,
from 8 to 48 in. wide and 50 to 1,700 ft. long; in addition, there were
8,000 elevator buckets, and other material. The storage capacity is
1,600,000 bushels, with a receiving capacity of 30,000, and a shipping
capacity of 20,000 bushels per hour.

* * * * *

THE FLOW OF WATER THROUGH TURBINES AND SCREW PROPELLERS.

[Footnote: Paper read before the British Association at Montreal.]

By Mr. ARTHUR RIGG, C.E.

Literature relating to turbines probably stands unrivaled among all that
concerns questions of hydraulic engineering, not so much in its voluminous
character as in the extent to which purely theoretical writers have ignored
facts, or practical writers have relied upon empirical rules rather than
upon any sound theory. In relation to this view, it may suffice to note
that theoretical deductions have frequently been based upon a
generalization that "streams of water must enter the buckets of a turbine
without shock, and leave them without velocity." Both these assumed
conditions are misleading, and it is now well known that in every good
turbine both are carefully disobeyed. So-called practical writers, as a
rule, fail to give much useful information, and their task seems rather in
praise of one description of turbine above another. But generally, it is of
no consequence whatever how a stream of water may be led through the
buckets of any form of turbine, so long as its velocity gradually becomes
reduced to the smallest amount that will carry it freely clear of the
machine.

The character of theoretical information imparted by some _Chicago Journal
of Commerce_, dated 20th February, 1884. There we are informed that "the
height of the fall is one of the most important considerations, as the same
stream of water will furnish five times the horse power at ten ft. that it
will at five ft. fall." By general consent twice two are four, but it has
been reserved for this imaginative writer to make the useful discovery that
sometimes twice two are ten. Not until after the translation of Captain
Morris' work on turbines by Mr. E. Morris in 1844, was attention in America
directed to the advantages which these motors possessed over the gravity
wheels then in use. A duty of 75 per cent. was then obtained, and a further
study of the subject by a most acute and practical engineer, Mr. Boyden,
led to various improvements upon Mr. Fauneyron's model, by which his
experiments indicated the high duty of 88 per cent. The most conspicuous
addition made by Mr. Boyden was the diffuser. The ingenious contrivance had
the effect of transforming part of whatever velocity remained in the stream
after passing out of a turbine into an atmospheric pressure, by which the
corresponding lost head became effective, and added about 3 per cent. to
the duty obtained. It may be worth noticing that, by an accidental
application of these principles to some inward flow turbines, there is
obtained most, if not all, of whatever advantage they are supposed to
possess, but oddly enough this genuine advantage is never mentioned by any
of the writers who are interested in their introduction or sale. The
well-known experiments of Mr. James B. Francis in 1857, and his elaborate
report, gave to hydraulic engineers a vast store of useful data, and since
that period much progress has been made in the construction of turbines,
and literature on the subject has become very complete.

In the limits of a short paper it is impossible to do justice to more than
one aspect of the considerations relating to turbines, and it is now
proposed to bring before the Mechanical Section of the British Association
some conclusions drawn from the behavior of jets of water discharged under
pressure, more particularly in the hope that, as water power is extremely
abundant in Canada, any remarks relating to the subject may not fail to
prove interesting.

Between the action of turbines and that of screw propellers exists an exact
parallelism, although in one case water imparts motion to the buckets of a
turbine, while in the other case blades of a screw give spiral movement to
a column of water driven aft from the vessel it propels forward. Turbines
have been driven sometimes by impact alone, sometimes by reaction above,
though generally by a combination of impact and reaction, and it is by the
last named system that the best results are now known to be obtained.

The ordinary paddles of a steamer impel a mass of water horizontally
backward by impact alone, but screw propellers use reaction somewhat
disguised, and only to a limited extent. The full use and advantages of
reaction for screw propellers were not generally known until after the
publication of papers by the present writer in the "Proceedings" of the
Institution of Naval Architects for 1867 and 1868, and more fully in the
"Transactions" of the Society of Engineers for 1868. Since that time, by
the author of these investigations then described, by the English
Admiralty, and by private firms, further experiments have been carried out,
some on a considerable scale, and all corroborative of the results
published in 1868. But nothing further has been done in utilizing these
discoveries until the recent exigencies of modern naval warfare have led
foreign nations to place a high value upon speed. Some makers of torpedo
boats have thus been induced to slacken the trammels of an older theory and
to apply a somewhat incomplete form of the author's reaction propeller for
gaining some portion of the notable performance of these hornets of the
deep. Just as in turbines a combination of impact and reaction produces the
maximum practical result, so in screw propellers does a corresponding gain
accompany the same construction.

[Illustration: FIG. 1.]

[Illustration: FIG. 2.]

_Turbines_.--While studying those effects produced by jets of water
impinging upon plain or concave surfaces corresponding to buckets of
turbines, it simplifies matters to separate these results due to impact
from others due to reaction. And it will be well at the outset to draw a
distinction between the nature of these two pressures, and to remind
ourselves of the laws which lie at the root and govern the whole question
under present consideration. Water obeys the laws of gravity, exactly like
every other body; and the velocity with which any quantity may be falling
is an expression of the full amount of work it contains. By a sufficiently
accurate practical rule this velocity is eight times the square root of the
head or vertical column measured in feet. Velocity per second = 8 sqrt
(head in feet), therefore, for a head of 100 ft. as an example, V = 8 sqrt
(100) = 80 ft. per second. The graphic method of showing velocities or
pressures has many advantages, and is used in all the following diagrams.
Beginning with purely theoretical considerations, we must first recollect
that there is no such thing as absolute motion. All movements are relative
to something else, and what we have to do with a stream of water in a
turbine is to reduce its velocity relatively to the earth, quite a
different thing to its velocity in relation to the turbine; for while the
one may be zero, the other may be anything we please. ABCD in Fig. 1
represents a parallelogram of velocities, wherein AC gives the direction of
a jet of water starting at A, and arriving at C at the end of one second or
any other division of time. At a scale of 1/40 in. to 1 ft., AC represents
80 ft., the fall due to 100 ft. head, or at a scale of 1 in. to 1 ft., AC
gives 2 ft., or the distance traveled by the same stream in 1/40 of a
second. The velocity AC may be resolved into two others, namely, AB and AD,
or BC, which are found to be 69.28 ft. and 40 ft. respectively, when the
angle BAC--generally called _x_ in treatises on turbines--is 30 deg. If,
however, AC is taken at 2 ft., then A B will be found = 20.78 in., and BC =
12 in. for a time of 1/40 or 0.025 of a second. Supposing now a flat plate,
BC = 12 in. wide move from DA to CB during 0.025 second, it will be readily
seen that a drop of water starting from A will have arrived at C in 0.025
second, having been flowing along the surface BC from B to C without either
friction or loss of velocity. If now, instead of a straight plate, BC, we
substitute one having a concave surface, such as BK in Fig. 2, it will be
found necessary to move it from A to L in 0.025 second, in order to allow a
stream to arrive at C, that is K, without, in transit, friction or loss of
velocity. This concave surface may represent one bucket of a turbine.
Supposing now a resistance to be applied to that it can only move from A to
B instead of to L. Then, as we have already resolved the velocity A C into
AB and BC, so far as the former (AB) is concerned, no alteration occurs
whether BK be straight or curved. But the other portion, BC, pressing
vertically against the concave surface, BK, becomes gradually diminished in
its velocity in relation to the earth, and produces and effect known as
"reaction." A combined operation of impact and reaction occurs by further
diminishing the distance which the bucket is allowed to travel, as, for
examples, to EF. Here the jet is impelled against the lower edge of the
bucket, B, and gives a pressure by its impact; then following the curve BK,
with a diminishing velocity, it is finally discharged at K, retaining only
sufficient movement to carry the water clear out of the machine. Thus far
we have considered the movement of jets and buckets along AB as straight
lines, but this can only occur, so far as buckets are concerned, when their
radius in infinite. In practice these latter movements are always curves of
more or less complicated form, which effect a considerable modification in
the forms of buckets, etc., but not in the general principles, and it is
the duty of the designer of any form of turbine to give this consideration
its due importance. Having thus cleared away any ambiguity from the terms
"impact," and "reaction," and shown how they can act independently or
together, we shall be able to follow the course and behavior of streams in
a turbine, and by treating their effects as arising from two separate
causes, we shall be able to regard the problem without that inevitable
confusion which arises when they are considered as acting conjointly.
Turbines, though driven by vast volumes of water, are in reality impelled
by countless isolated jets, or streams, all acting together, and a clear
understanding of the behavior of any one of these facilitates and concludes
a solution of the whole problem.

_Experimental researches_.--All experiments referred to in this paper were
made by jets of water under an actual vertical head of 45 ft., but as the
supply came through a considerable length of 1/2 in. bore lead piping, and
many bends, a large and constant loss occurred through friction and bends,
so that the actual working head was only known by measuring the velocity of
discharge. This was easily done by allowing all the water to flow into a
tank of known capacity. The stop cock had a clear circular passage through
it, and two different jets were used. One oblong measured 0.5 in. by 0.15
in., giving an area of 0.075 square inch. The other jet was circular, and
just so much larger than 1/4 in. to be 0.05 of a square inch area, and the
stream flowed with a velocity of 40 ft. per second, corresponding to a head
of 25 ft. Either nozzle could be attached to the same universal joint, and
directed at any desired inclination upon the horizontal surface of a
special well-adjusted compound weighing machine, or into various bent tubes
and other attachments, so that all pressures, whether vertical or
horizontal, could be accurately ascertained and reduced to the unit, which
was the quarter of an ounce. The vertical component _p_ of any pressure P
may be ascertained by the formula--

_p_ = P sin alpha,

where alpha is the angle made by a jet against a surface; and in order to
test the accuracy of the simple machinery employed for these researches,
the oblong jet which gave 71 unit when impinging vertically upon a circular
plate, was directed at 60 deg. and 45 deg. thereon, with results shown in
Table I., and these, it will be observed, are sufficiently close to theory
to warrant reliance being placed on data obtained from the simple weighing
machinery used in the experiment.

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