Scientific American Supplement, No. 363, December 16, 1882

V >> Various >> Scientific American Supplement, No. 363, December 16, 1882

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Space fails, or I should mention in detail Mr. Joule's experiments on
magnetism and electro-magnets, referred to at the commencement of this
sketch. He discovered the now celebrated change of dimensions produced
by the magnetization of soft iron by the current. The peculiar noise
which accompanies the magnetization of an iron bar by the current,
sometimes called the "magnetic tick," was thus explained.

Mr. Joule's improvements in galvanometers have already been incidentally
mentioned, and the construction by him of accurate thermometers has been
referred to. It should never be forgotten that _he first_ used small
enough needles in tangent galvanometers to practically annul error from
want of uniformity of the magnetic field. Of other improvements and
additions to philosophical instruments may be mentioned a thermometer,
unaffected by radiation, for measuring the temperature of the
atmosphere, an improved barometer, a mercurial vacuum pump, one of the
very first of the species which is now doing such valuable work, not
only in scientific laboratories, but in the manufacture of incandescent
electric lamps, and an apparatus for determining the earth's horizontal
magnetic force in absolute measure.

Here this imperfect sketch must close. My limits are already passed. Mr.
Joule has never been in any sense a public man; and, of those who know
his name as that of the discoverer who has given the experimental basis
for the grandest generalization in the whole of physical science, very
few have ever seen his face. Of his private character this is scarcely
the place to speak. Mr. Joule is still among us. May he long be spared
to work for that cause to which he has given his life with heart-whole
devotion that has never been excelled.

In June, 1878, he received a letter from the Earl of Beaconsfield
announcing to him that Her Majesty the Queen had been pleased to grant
him a pension of L200 per annum. This recognition of his labors by his
country was a subject of much gratification to Mr. Joule.

Mr. Joule received the Gold Royal Medal of the Royal Society in 1852,
the Copley Gold Medal of the Royal Society in 1870, and the Albert Medal
of the Society of Arts from the hand of the Prince of Wales in 1880.

J. T. BOTTOMLEY.

* * * * *

THE NEW YORK CANALS.

The recent adoption of the constitutional amendment abolishing tolls on
the canals of New York State has revived interest in these water ways.
The overwhelming majority by which the measure was passed shows, says
the _Glassware Reporter_, that the people are willing to bear the cost
of their management by defraying from the public treasury all expenses
incident to their operation. That the abolition of the toll system will
be a great gain to the State seems to be admitted by nearly everybody,
and the measure met with but little opposition except from the railroad
corporations and their supporters.

At as early a date as the close of the Revolutionary War, Mr. Morris had
suggested the union of the great lakes with the Hudson River, and in
1812 he again advocated it. De Witt Clinton, of New York, one of the
most, valuable men of his day, took up the idea, and brought the leading
men of his State to lend him their support in pushing it. To dig a
canal all the way from Albany to Lake Erie was a pretty formidable
undertaking; the State of New York accordingly invited the Federal
government to assist in the enterprise.

The canal was as desirable on national grounds as on any other, but the
proposition met with a rebuff, and the Empire State then resolved to
build the canal herself. Surveyors were sent out to locate a line for
it, and on July 4, 1817, ground was broken for the canal by De Witt
Clinton, who was then Governor of the State.

The main line, from Albany, on the Hudson, to Buffalo, on Lake Erie,
measures 363 miles in length, and cost $7,143,789. The Champlain,
Oswego, Chemung, Cayuga, and Crooked Lake canals, and some others, join
the main line, and, including these branch lines, it measures 543 miles
in length, and cost upward of $11,500,000. This canal was originally 40
feet in breadth at the water line, 28 feet at the bottom, and 4 feet in
depth. Its dimensions proved too small for the extensive trade which it
had to support, and the depth of water was increased to 7 feet, and the
extreme breadth of the canal to 60 feet. There are 84 locks on the main
line. These locks, originally 90 feet in length and 15 in breadth, and
with an average lift of 8 feet 2 inches, have since been much enlarged.
The total rise and fall is 692 feet. The towpath is elevated 4 feet
above the level of the water, and is 10 feet in breadth. At Lockport the
canal descends 60 feet by means of 5 locks excavated in solid rock, and
afterward proceeds on a uniform level for a distance of 63 miles to the
Genesee River, over which it is carried on an aqueduct having 9 arches
of 50 feet span each. Eight and a half miles from this point it passes
over the Cayuga marsh, on an embankment 2 miles in length, and in some
places 70 feet in height. At Syracuse, the "long level" commences, which
extends for a distance of 691/2 miles to Frankfort, without an intervening
lock. After leaving Frankfort, the canal crosses the river Mohawk, first
by an aqueduct 748 feet in length, supported on 16 piers, elevated 25
feet above the surface of the river, and afterward by another aqueduct
1,188 feet in length, and emerges into the Hudson at Albany.

This great work was finished in 1825, and its completion was the
occasion of great public rejoicing. The same year that the Erie Canal
was begun, ground was broken for a canal from Lake Champlain to the
Hudson, sixty-three miles in length. This work was completed in 1823.

The construction of these two water ways was attended with the most
interesting consequences. Even before they were completed their value
had become clearly apparent. Boats were placed upon the Erie Canal as
fast as the different levels were ready for use, and set to work in
active transportation. They were small affairs compared with those of
the present day, being about 50 or 60 tons burden, the modern canal boat
being 180 or 200 tons. Small as they were, they reduced the cost of
transportation immediately to one-tenth what it had been before. A ton
of freight by land from Buffalo to Albany cost at that time $100. When
the canal was open its entire length, the cost of freight fell from
fifteen to twenty-five dollars a ton, according to the class of article
carried; and the time of transit from 20 to 8 days, Wheat at that time
was worth only $33 a ton in western New York, and it did not pay to send
it by land to New York. When sent to market at all, it was floated down
the Susquehanna to Baltimore, as being the cheapest and best market.
The canal changed that. It now became possible to send to market a wide
variety of agricultural produce--fruit, grain, vegetables, etc.--which,
before the canal was built, either had no value at all, or which could
be disposed of to no good advantage. It is claimed by the original
promoters of the Erie Canal, who lived to see its beneficial effects
experienced by the people of the country, that their work, costing less
than $8.000,000 and paying its whole cost of construction in a very
few years, added $100,000,000 to the value of the farms of New York by
opening up good and ready markets for their products. The canal had
another result. It made New York city the commercial metropolis of the
country. An old letter, written by a resident of Newport, R. I., in that
age, has lately been discovered, which speaks of New York city, and
says: "If we do not look out, New York will get ahead of us." Newport
was then one of the principal seaports of the country; it had once been
the first. New York city certainly did "get ahead of us" after the Erie
Canal was built. It got ahead of every other commercial city on the
coast. Freight, which had previously gone overland from Ohio and the
West to Pittsburg, and thence to Philadelphia, costing $120 a ton
between the two cities named, now went to New York by way of the Hudson
River and the Erie Canal and the lakes. Manufactures and groceries
returned to the West by the same route, and New York became a
flourishing and growing emporium immediately. The Erie Canal was
enlarged in 1835, so as to permit the passage of boats of 100 tons
burden, and the result was a still further reduction of the cost of
freighting, expansion of traffic, and an increase of the general
benefits conferred by the canal. The Champlain Canal had an effect upon
the farms and towns lying along Lake Champlain, in Vermont and New York,
kindred in character to that above described in respect to the Erie
Canal. It brought into the market lands and produce which before had
been worthless, and was a great blessing to all concerned.

There can be no doubt that the building of the Erie Canal was the wisest
and most far-seeing enterprise of the age. It has left a permanent and
indelible mark upon the face of the republic of the United States in the
great communities it has directly assisted to build up at the West, and
in the populous metropolis it created at the mouth of the Hudson River.
None of the canals which have been built to compete with it have yet
succeeded in regaining for their States what was lost to them when the
Erie Canal went into operation. This water route is still the most
important artificial one of its class in the country, and is only
equaled by the Welland Canal in Canada, which is its closest rival. Now
that it is free, it will retain its position as the most popular water
route to the sea from the great West. The Mississippi River will divert
from it all the trade flowing to South America and Mexico; but for the
northwest it will be the chief water highway to the ocean.

* * * * *

COTTRAU'S LOCOMOTIVE FOR ASCENDING STEEP GRADES.

We borrow, from our contemporary _La Nature_, the annexed figure,
illustrating an ingenious type of locomotive designed for equally
efficient use on both level surfaces and heavy grades.

[Illustration: COTTRAU'S LOCOMOTIVE FOR ASCENDING STEEP GRADES.]

As well known, all the engines employed on level roads are provided with
large driving wheels, which, although they have a comparatively feeble
tractive power, afford a high speed, while, on the contrary, those that
are used for ascending heavy grades have small wheels that move slowly,
but possess, as an offset, a tractive power that enables them to
overcome the resistances of gravity.

M. Cottrau's engine possesses the qualities of both these types, since
it is provided with wheels of large and small diameter, that may be used
at will. These two sets of wheels, as may be seen from the figure, are
arranged on the same driving axle. The large wheels are held apart
the width of the ordinary track, while the small wheels are placed
internally, or as in the case represented in the figure, externally.
These two sets of wheels, being fixed solidly to the same axle, revolve
together.

On level surfaces the engine rests on the large wheels, which revolve
in contact with the rails of the ordinary track, and it then runs with
great speed, while the auxiliary wheels revolve to no purpose. On
reaching an ascent, on the contrary, the engine meets with an elevated
track external or internal to the ordinary one, and which engages with
the auxiliary wheels. The large wheels are then lifted off the ordinary
track and revolve to no purpose. In both cases, the engine is placed
under conditions as advantageous as are those that are built especially
for the two types of roads. The idea appears to be a very ingenious one,
and can certainly be carried out without disturbing the working of the
locomotive. In fact, the same number of piston strokes per minute may
be preserved in the two modes of running, so as to reduce the speed in
ascending, in proportion to the diameters of the wheels. There will thus
occur the same consumption of steam. On another hand, there is nothing
to prevent the boiler from keeping up the same production of steam, for
it has been ascertained by experience, on the majority of railways, that
the speed of running has no influence on vaporization, and that the same
figures may be allowed for passenger as for freight locomotives.

The difficulties in the way of construction that will be met with in the
engine under consideration will be connected with the placing of the
double wheels, which will reduce the already limited space at one's
disposal, and with the necessity that there will be of strengthening all
the parts of the mechanism that are to be submitted to strain.

The installation of the auxiliary track will also prove a peculiarly
delicate matter; and, to prevent accidents, some means will have to be
devised that will permit the auxiliary wheels to engage with this
track very gradually. Still, these difficulties are perhaps not
insurmountable, and if M. Cottrau's ingenious arrangement meets with
final success in practice, it will find numerous applications.

* * * * *

BACHMANN'S STEAM DRIER.

The apparatus shown in the annexed cuts is capable of effecting a
certain amount of saving in the fuel of a generator, and of securing a
normal operation in a steam engine. If occasion does not occur to blow
off the motive cylinder frequently, the water that is carried over
mechanically by the steam, or that is produced through condensation in
the pipes, accumulates therein and leaks through the joints of the cocks
and valves. This is one of the causes that diminish the performance of
the motor.

[Illustration: BACHMANN'S STEAM DRIER. FIG. 1.]

The steam drier under consideration has been devised by Mr. Bachmann
for the purpose of doing away with such inconveniences. When applied to
apparatus employed in heating, for cooking, for work in a vacuum, it may
be affixed to the pipe at the very place where the steam is utilized, so
as to draw off all the water from the mixture.

As shown by the arrows in Fig 1, the steam enters through the orifice,
D, along with the water that it carries, gives up the latter at P, and
is completely dried at the exit, R. The partition, g, is so arranged
as to diminish the section of the steam pipe, in order to increase the
effect of the gravity that brings about the separation of the mixture.
The water that falls into the space, P, is exhausted either by means of
a discharge cock (Fig. 1), which gives passage to the liquid only, or
by the aid of an automatic purge-cock (Figs. 2 and 3), the locating of
which varies with the system employed. This arrangement is preferable
to the other, since it permits of expelling the water deposited in the
receptacle, P, without necessitating any attention on the part of the
engine-man.

* * * * *

H.S. PARMELEE'S PATENT AUTOMATIC SPRINKLER.

The inventor says: "The automatic sprinkler is a device for
automatically extinguishing fires through the release of water by means
of the heat of the fire, the water escaping in a shower, which is thrown
in all directions to a distance of from six to eight feet. The sprinkler
is a light brass rose, about 11/2 inches diameter and less than two inches
high entire, the distributer being a revolving head fitted loosely to
the body of the fixed portion, which is made to screw into a half inch
tube connection. The revolution of the distributer is effected by the
resistance the water meets in escaping through slots cut at an angle
in the head. The distribution of water has been found to be the most
perfect from this arrangement. Now, this distributing head is covered
over with a brass cap, which is soldered to the base beneath with an
alloy which melts at from 155 to 160 degrees. No water can escape until
the cap is removed. The heat of an insignificant fire is sufficient to
effect this, and we have the practical prevention of any serious damage
or loss through the multiplication of the sprinkler.

[Illustration: PARMELEE'S PATENT AUTOMATIC SPRINKLER. FIG. 1.--Section
of Sprinkler with Cap on.]

The annexed engravings represent the sprinkler at exact size for
one-half inch connection. Fig. 1 shows a section with the cap covering
over the sprinkler, and soldered on to the base. Fig. 2 shows the
sprinkler with the cap off, which, of course, leaves the water free to
run from the holes in fine spray in all directions. Fig. 1 shows the
base hollowed out so as to allow the heat to circulate in between the
pipe and the base of the sprinkler, thus allowing the heat to operate on
the _inside_ as well as on the outside of the sprinkler; thus, in case
of fire, it is very quickly heated through sufficiently to melt the
fusible solder. These sprinklers are all tested at 500 lb., consequently
they can never leak, and cannot possibly be opened, except by heat,
by any one. As the entire sprinkler is covered by a heavy brass cap,
soldered on, it cannot by any means be injured, nor can the openings in
the revolving head ever become filled with dust.

[Illustration: PARMELEE'S PATENT AUTOMATIC SPRINKLER. FIG.2--Sprinkler
with cap off.]

It is so simple as to be easily understood by any one. As soon as the
sprinkler becomes heated to 155 degrees, the cap will become unsoldered,
and will then immediately be blown entirely off by the force of the
water in the pipes and sprinkler. These caps cannot remain on after
the fusible metal melts, if there is the least force of water. A man's
breath is sufficient to blow them off.

The arrangement commences with one or more main supply pipes, either fed
from a city water pipe or from a tank, as the situation will admit.
If desired, the tank need only be of sufficient size to feed a few
sprinklers for a short time, and then dependence must be placed upon
a pump for a further supply of water, if necessary. The tank, however
small, will insure the automatic and prompt working of the sprinklers
and alarm, and by the time the tank shall become empty the pumps can
be got at work. It is most desirable, however, in all cases to have an
abundant water supply without resorting to pumps, if it is possible.

In the main supply pipe or pipes is placed our patent alarm valve,
which, as soon as there is any motion of the water in the pipe, opens,
and moves a lever, which, by connecting with a steam whistle valve by
means of a wire, will blow the whistle and will continue to do so until
either the steam or the water is stopped. Tins constitutes the alarm,
and is positive in its motion. No water can possibly flow from the line
of pipes without opening this valve and blowing the whistle. We also put
in an automatic alarm bell when desired.

From the main pipe other pipes are run, generally lengthways of the
building, ten feet from each side and twenty feet apart. At every ten
feet on these pipes we place five feet of three-quarter inch pipe,
reaching each side, at the end of which is placed the sprinkler in an
elbow pointing toward the ceiling. This arrangement is as we place them
in all cotton and woolen mills, but may be varied to suit different
styles of buildings.

The sprinkler is made of brass, and has a revolving head, with four
slots, from which the water flies in a very fine and dense spray on
everything, and filling the air very completely for a radius of seven or
eight feet all around; thus rendering the existence of any fire in that
space perfectly impossible; and as the sprinklers are only placed ten
feet apart, and a fire cannot start at a greater distance than from five
to six feet from one or more of them, it is assured that all parts of a
building are fully protected.

Over each one of these sprinklers is placed a brass cap, which fits
closely over and passes below the base, where it is soldered on with a
fusible metal that melts as soon as it is heated to 155 degrees.

As soon as a fire starts in any part of a building, heat will be
generated and immediately rise toward the ceiling, and the sprinkler
nearest the fire will become heated in a very few moments to the
required 155 degrees, when the cap will become loosened and will be
forced off by the power of the water. The water will then be spread in
fine spray on the ceiling over the fire, also directly on the fire and
all around for a diameter of from fourteen to eighteen feet. This spray
has been fully tried, and it is found to be entirely sufficient to
extinguish any fire within its reach which can be made of any ordinary
materials.

As soon as the cap on any sprinkler becomes loosened by the heat of a
fire and is forced off, a current of water is produced in the main pipe
where the alarm valve is placed, and as the passage through it is dosed,
the water cannot pass without opening the valve and thus moving the
lever to which the steam whistle valve is attached; by this motion the
whistle valve is opened, and the whistle will blow until it is stopped
by some one."

* * * * *

INSTRUMENT FOR DRAWING CONVERGING STRAIGHT LINES.

[Footnote: Paper by Prof. Fr. Smigaglia, read at the reunion of the
Engineers and Architects of Rome.]

1. LET A and B be two fixed points and A C and C B two straight lines
converging at C and moving in their plane so as to always remain based
on this point (Fig. 1). The geometrical place of the positions occupied
by C is the circumference of the circle which passes through the three
points A, B, and C. Now let C F be a straight line passing through C. On
prolonging it, it will meet the circumference A C B I at a point I. If
the system of three converging--lines takes a new position A C' F B,
it is evident F' B' prolonged will pass through I, because the angles
[alpha] and [beta] are invariable for any position whatever of the
system.

[Illustration: Fig. 1.]

2. In the particular case in which [alpha] = [beta] (Fig. 2), the point
I is found at the extremity of the diameter, and, consequently, for a
given distance A B, or for a given length C D, such point will be at its
maximum distance from C.

[Illustration: Fig. 2.]

3. This granted, it is easy to construct an instrument suitable for
drawing converging lines which shall prove useful to all those who have
to do with practical perspective. For this purpose it is only necessary
to take three rulers united at C (Fig. 3), to rest the two A C and C B
against two points or needles A and B, and to draw the lines with the
ruler C F, in placing the system (Sec. 1) in all positions possible. The
three rulers may be inclined in any way whatever toward each other, but
(Sec. 2) it is preferable to take the case where [alpha] = [beta].

[Illustration: Fig. 3.]

4. Let us suppose that the instrument passes from the position I to
position III (Fig. 4). Then the ruler C A will come to occupy the
position B A, from the fact that the instrument, continuing to move in
the same direction, will roll around the point B. It is well, then, to
manage so that the system shall have another point of support. For that
reason I prolong C B, take B C' = B C, draw C' I, and describe the
circumference--the geometrical place of the points C'. I take C' D = C'
B and obtain at D the position of the fixed point at which the needle
is inserted. In Fig. 4 are represented different positions of the
instrument; and it may be seen that all the points C C', and the centers
O O', are found upon the circumferences that have their center at I.

[Illustration: Fig. 4.]

5. The manipulation and use of the instrument are of the simplest
character. Being given any two straight converging lines whatever,
[alpha] [beta] and [gamma] [delta] (Fig. 5), in order to trace all the
others I insert a needle at A and arrange the instrument as seen at S. I
draw A B and A B', and from there carry it to S' in such a way that the
ruler being on [gamma] [delta], one of the resting rulers passes through
A. I draw the line C B which meets A B at the point B, the position
sought for the second needle. In order to draw the straight lines which
are under [alpha] [beta], it is only necessary to hold the needle A in
place and to fix one at B', making A B' = A B. In this case S" indicates
one of the positions of the instrument.

[Illustration: Fig. 5.]

6. The point A was chosen arbitrarily, but it is evident that that of
the needles depends on its distance from the point of convergence. Thus,
on taking A' instead of A in the case of Fig. 3, they approach, while
the contrary happens on choosing the point A". It is clear that the
different positions that a needle A may take are found on a straight
line which runs to the point of meeting.

7. If the instrument were jointed or hinged at C, that is to say, so
that we could at will modify the angle of the resting ruler, we might
make the position of the needles depend on such angle, and conversely.

8. Being given the length C I (Fig. 6), to establish the position of the
needles so that all the lines outside of the sheet shall converge at I.
To do this, it is well to determine C D, and then to draw the straight
line A D B perpendicular to C I, so as to have at A and B the points at
which the needles must be placed.

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