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SCIENTIFIC AMERICAN


A WEEKLY JOURNAL OF PRACTICAL INFORMATION, ART, SCIENCE, MECHANICS,
CHEMISTRY, AND MANUFACTURES.


NEW YORK, DECEMBER 14, 1878.

Vol. XXXIX.--No. 24. [NEW SERIES.]

[$3.20 per Annum [POSTAGE PREPAID.]]

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CONTENTS.

(Illustrated articles are marked with an asterisk.)

  Alum in baking powders
  Alum in bread                    376
  Argonaut, or Paper Nautilus*     375
  Astronomical notes               377
  Babbitt metal, to make [5]       378
  Belts, rubber, slipping [6]      378
  Bench, saw, Casson's*            374
  Boot polish liquid [8]           378
  Butter, to color [16]            378
  Canal, ship, Belgian*            367
  Economy, machine shop            371
  Eggs, preservation of            375
  Electric light, Werdermann*      373
  Engineers, warning to            367
  Engine, steam, valve yoke [48]   379
  Exterminator, roach [57]         379
  Filter for rain water [19]       378
  Foot power, new*                 370
  Glass, iridescent                368
  Glass, to make a hole in         375
  Hair, to prevent falling out [42]379
  Inks, sympathetic                377
  Invention, reward of             371
  Inventions, new,                 370
  Inventions, new agricultural     377
  Inventions, new mechanical       374
  Inventors, bait for              374
  Iron and steel, preservation of  367
  Iron, malleable, to make [43]    379
  Leaves, culinary uses for        370
  Line, straight, to draw* [36]    379
  Mechanics, amateur*              371
  Mexico, progress of science in   376
  Microphone as a thief catcher    375
  Naphtha and benzine              377
  Nitrate of silver, reduction of  377
  Notes and queries                378
  Oil notes                        372
  Petroleum and gold               377
  Petroleum, progress of           368
  Poultices                        374
  Quinine, effects of on hearing   374
  Railroad, first in U. S. [2]     378
  Rails and railway accidents      368
  Railway notes                    373
  Sanitary Science in the U. S.    369
  Screw heads, blue color for [4]  378
  Sheep husbandry, American        375
  Shutter fastener, new*           370
  Silver mill in the clouds        374
  Spider, trap-door*               375
  Sprinkler, garden, improved*     370
  Telescope, sunshade for [3]      378
  Tools, steel, to temper [55]     379
  Tree, tallest in the world       375
  Tree trunks elongation of        376
  Trees, felling by electricity    370
  Tubing, to satin finish [51]     379
  Vise, an improved*               370
  White lead, to test [14]         378
  Wire clothing for cylinders*     377
  Work, the limit of               368

       *       *       *       *       *




THE BELGIAN SHIP CANAL.


The ship canal from Ghent to Terneuzen was originally laid out with
many bends, rendering navigation difficult; it had a depth of 14 feet
4 inches and a width of 98 feet 6 inches at the water level. The works
which are at present in course of execution have especially for their
object the deepening of the canal to 21 feet 3 inches, with a width
of 55 feet 9 inches at the bottom and 103 feet 9 inches on the water
line. The <DW72>s have a uniform inclination of 1 to 3, and the towing
paths on each side are placed 6 feet 6 inches above the water level,
and are 32 feet 8 inches wide. In many instances also the course of
the canal has been altered and straightened for the improvement of
navigation; several important diversions have been made for this
purpose. The excavation has been effected by hand, by dredging, and by
the Couvreux excavator, figured as below in _Engineering_.

The earth excavated was carried to spoil, and in many cases was
employed to form dikes inclosing large areas, which served as
receptacles for the semi-liquid material excavated by the dredging
machines with the long conductors; the Couvreux excavator used will be
readily understood from the engraving. It had already done service on
the Danube regulation works. The material with which it had to deal,
however, was of a more difficult nature, being a fine sand charged
with water and very adherent. The length of track laid for the
excavator was about 3 miles along the side of the old canal, which had
been previously lowered to the level of the water.

       *       *       *       *       *




PRESERVATION OF IRON AND STEEL FROM OXIDATION.


We are indebted to J. Pechar, Railway Director in Teplitz, Bohemia,
for the first official report in English from the Paris International
Exhibition which has come to hand. This volume contains the report
on the coal and iron products in all countries of the world, and is
valuable for its statistical and other information, giving, as it
does, the places where the coal and minerals are found, and the
quantities of each kind produced, for what it is used, and to what
other countries it is exported. The able compiler of these statistics
in the introduction of his report gives the following account of
the means recommended by Professor Barff, of London, for preventing
oxidation, which is being considerably used abroad. The writer says:

It is well known that the efficient preservation of iron against
rusting is at present only provided for in cases where human life
would be endangered by failure, as in the case of railway bridges
and steamers. Thus, for example, at Mr. Cramer-Klett's ironworks at
Nuremberg every piece of iron used for his bowstring bridges is dipped
in oil heated to eight hundred degrees. The very great care which
is at present taken in this matter may be judged from the current
practice of most bridge and roofing manufacturers. Every piece of
iron before being riveted in its place is cleaned from rust by being
immersed in a solution of hydrochloric acid. The last traces of free
acid having been cleared away, at first by quicklime and afterward by
a copious ablution with hot water, the piece is immediately immersed
in hot linseed oil, which protects every part of the surface from the
action of the atmosphere. Afterward it is riveted and painted.

Notwithstanding all this, the painting requires continual and
careful renewal. On the Britannia Bridge, near Bangor, the painter is
permanently at work; yet, in spite of all this care and expense, rust
cannot be entirely avoided. The age of iron railway bridges is still
too short to enable us to draw conclusions as to the probabilities of
accidents. Now, Professor Barff has discovered a process by which
iron may be kept from rusting by being entirely coated with its own
sesquioxide. A piece of iron exposed to the action of superheated
steam, in a close chamber and under a certain pressure, becomes
gradually covered by a skin of this black oxide, of a thickness
depending upon the temperature of the steam and the duration of
the experiment. For instance, exposure during five hours to steam
superheated to five hundred degrees will produce a hermetical coating
capable of resisting for a considerable time the application of emery
paper and of preserving the iron from rust even in a humid atmosphere,
if under shelter from the weather. If the temperature is raised to
1,200 degrees, and the time of exposure to six or seven hours, the
skin of sesquioxide will resist every mechanical action, and the
influence of any kind of weather. The sesquioxide being harder than
the iron itself, and adhering to its surface even more firmly than the
atoms of iron do to each other, there is an increased resistance not
only to chemical but also to mechanical action. The surface is not
altered by the process in any other respect, a plain forging retaining
its roughness, a polished piece its smooth surface. If the skin is
broken away oxidation takes place, but only just on the spot from
which the oxide has been removed. If Professor Barff's experiments
are borne out by practice, this invention may become of very great
importance. It is within the bounds of probability that it may enable
iron, by increasing its facility in competing with wood, to recover,
at least for a considerable time, even more than the ground it has
lost by the extraordinary extension of the use of steel. Iron is
already being used for building purposes to a large extent; but
oxidation once thoroughly prevented it will be able to take the place
of wood and stone to a still greater degree. Iron roofing may be
made quite as light as that of wood, and of greater strength, by a
judicious arrangement and use of T iron.

       *       *       *       *       *




WARNING TO LOCOMOTIVE ENGINEERS.


Drs. Charles M. Cresson and Robert E. Rogers, of this city, says
the Philadelphia _Ledger_, well known as experts in chemistry and
dynamics, were appointed by the Reading Railroad Company to inquire
into and report upon the causes of the recent explosion of the boiler
of the express locomotive "Gem," at Mahanoy City, by which five lives
were lost. Their report, which is designed to cover the whole scope
of a most careful investigation, is not yet made public, but they have
arrived at the following specific conclusion, which we give in their
own language: "We are, therefore, of the opinion that the explosion of
the boiler of the locomotive 'Gem,' was produced by the projection of
foam upon the heated crown bars of the furnace, caused by suddenly
and widely opening the safety valve, at a time when the water had been
permitted to get so low as to overheat the crown of the furnace." This
is an important matter that should be carefully noted by locomotive
and other engineers.

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VOL. XXXIX., No. 24. [NEW SERIES.] Thirty-third Year. NEW YORK,
SATURDAY, DECEMBER 14, 1878.

       *       *       *       *       *




TABLE OF CONTENTS OF

THE SCIENTIFIC AMERICAN SUPPLEMENT

No. 154,

For the Week ending December 14, 1878.

Price 10 cents. For sale by all newsdealers.


I. ENGINEERING AND MECHANICS.--Portable Steam Pumping Engine, 1
  engraving.--New Bone Crushing Mill, 2 engravings.--Picard's Boiler.
  Extraction of Salt from Salt Water.--Compressed Air Machines.
  Hydraulic vs. air pressure. Causes of the losses of power.
  Estimates of useful effects obtainable.--The St. Gothard Tunnel.
  By GEO. J. SPECHT, C.E.--Apparatus for Lifting Sunken Vessels,
  with 8 figures.--Russia Sheet Iron.--Manufacture of Artificial
  Stone.--Compressed Fuel.--The New Magnesi Process for Boiler Feed
  Water.

II. FRENCH INTERNATIONAL EXHIBITION OF 1878.--Wine Presses.
  Description of sixteen new and peculiar wine presses at the
  Exhibition, with 31 figures and 9 engravings. The Press Primat;
  Press Mabille; Press David; Samain Press; Marchand, Maupre,
  Boyries, Chapellier, Marmonier, Nogues, Mailhe, Moreau, Piquet,
  Delperoux, Terrel des Chenes, and Cassan fils Presses.

  The Algerian Exhibit. The street of Algiers, with 1
  illustration.--Woolen Fabrics.

III. ELECTRICITY, LIGHT, HEAT, ETC.--Electric Lighting. Estimate
  of the comparative heating effect in gas and electric lighting,
  and the consequent loss of power.--The Electric Light. Remarks on
  its economy.--The Present Bugbear of French Savants.

  New Planets.

  The Dutch Arctic Expedition. The Peak of Beerenburg, Spitzbergen,
  with 1 illustration.

IV. CHEMISTRY AND METALLURGY.--New Process for Separating Iodine
  and Bromine from Kelp.--Inoffensive Colors for Toys.--New Coloring
  Matters.--Tungsten.

  Ozone and the Atmosphere. By ALBERT R. LEEDS, Ph.D. Table of
  percentage of ozone contained in the atmosphere at various
  localities in the United States. Register of ozone observations
  for one month at Upper Saranac Lake, N. Y., giving thermometric
  and barometric observations, and full record of weather.
  Examination of methods in ozonometry. Preparation of ozone by
  electrolysis of water containing sulphuric acid, with 1 engraving.
  Preparation by electricity, with 1 engraving. Does the electric
  spark decompose potassium iodide? Collection and preservation of
  ozone. Preparation by chemical methods. Critical examination of
  ozonoscopes. Potassium iodide; starch; paper classification of
  ozonoscopes. Examination of ozonoscopes under certain conditions.

  Limits of the Combustibility of Gases.--The Diffusion of
  Salicylate of Soda.--Singular use of Fluorescein.--New Metal.
  Philippium By M. MARC DELAFONTAINE.--Better Pharmaceutical
  Education. By RICHARD V. MATTISON, Ph. G.--An El Dorado for
  Apothecaries.

V. MEDICINE AND HYGIENE.--The Science of Easy Chairs. The muscular
  conditions of fatigue, and how to obtain the greatest rest. How
  easy chairs should be made.

  Prof. Huxley on the Hand. Abstract of his inaugural lecture before
  the South London Workingmen's College.

  Paint from a Sanitary Point of View. The required abolition of
  absorbent surfaces in dwellings. Lead poisoning from paint not
  thoroughly dry. Cases described in which white lead paint in
  dwellings never dries, but gives off poisonous particles, which
  are inhaled by the inmates, causing depression, weakness headache,
  and loss of appetite. Zinc recommended in paint to avoid lead
  poisoning, and the new oxy-sulphide of Zinc described, with
  covering qualities equal to white lead.

  The Purification of Sewage. By HENRY ROBINSON, F.R.S. Paper
  read before the Sanitary Institute of Great Britain. Progress
  in purifying sewage by precipitation. The use of chemicals for
  precipitating, deodorizing, and disinfecting. Practical data on
  a large scale, with cost. Average number of gallons per head of
  population, etc., of the successful system now in operation at
  Coventry and Hertford. How the water is removed from the sludge by
  filter presses. Drying and removal of the sludge. Theoretical and
  actual values of the sludge for fertilizing.

VI. AGRICULTURE, HORTICULTURE, ETC.--The Broadside Steam Digger,
  with 1 engraving.--Shall I Plow the Lawn?--Bee Culture.

       *       *       *       *       *




PROGRESS OF PETROLEUM.


The efforts of the great majority of the Western Pennsylvania
petroleum producers to obtain relief from what they deem the
oppressive acts of the Standard Oil Company and the unjust
discriminations of the United Pipe Lines, and the various railroads
traversing the oil regions, have attracted more than usual attention
to the present condition of this industry and its possible future.

We would here explain that the Standard Oil Company originated in
Cleveland, Ohio, about twelve years ago, and was incorporated under
the laws of Ohio, with a nominal capital now, we are informed, of
$3,000,000, which, however, very inadequately represents the financial
strength of its members. It is now a combination of the most
prominent refiners in the country, and has before been credited with
manipulating the transportation lines to its own special advantage.

We can recall no instance of such serious hostility between parties
whose interests are at the same time of such magnitude and so nearly
identical; nor can we see what substantial, enduring benefit would
accrue to the producers in the event of their victory in the struggle.

They charge that the Standard Oil Company has become the controlling
power to fix prices and to determine the avenues by which the oil
shall be transported eastward for home consumption and for foreign
exportation; that the railway companies have given this company lower
rates than other parties for transporting the oil; and that through
the rates given to it by the railways the value of their property is
destroyed.

The reply, in effect, is, Granting all this to be true, what does
it amount to? Neither more nor less than that the managers of the
Standard Oil Company, by combination of capital, by intelligence and
shrewdness in the management of their operations, have built up a
successful business, and that they have so extended it by the use of
all practicable appliances, and by the purchase of the property of
competitors, that they do practically control the prices of oil, both
crude and refined, and that the uncombined capital of the other oil
producers, lacking the power, the intelligence, and the business skill
which combined capital can secure, cannot compete with the Standard
Oil Company. Now, is there any great wrong or injustice in this?

When brains can command capital it is always more successful in
business matters than any amount of brains without capital or capital
without brains. This result is the natural working out of the same
principle that is everywhere to be seen--some men are successful and
others are not.

It is the essence of communism to drag down those who succeed to the
level of the unsuccessful.

If men cannot compete with others in any business they must accept the
fact, and try some other employment.

If, through superior intelligence and capital, the Standard Oil
Company can control the oil business of Pennsylvania, then, according
to the principles of common sense, it must be permitted to do so.

What right, then, has the oil producer to complain? Why, if all that
is alleged is true, will they persist in sinking more wells, when,
as they say, they are controlled by the Standard Oil Company? No one
forces them to lose money by continuing in the business. Let them find
other employment. They do not show that the Standard Oil Company
does anything that combined capital on their part and equal business
ability could not effect.

The cry of monopoly in this case is altogether unfounded, those
opposed to the Standard Oil Company having just as much right to do
all that that company does, and, therefore, there can be no monopoly,
because they have no exclusive powers.

As to the railway companies, they can afford and have a right to
transport the tonnage offered them by the Standard Oil Company at less
cost, because it costs them less to do a regular and large business
than an irregular and smaller one. They would simply be acting in
accordance with business principles the world over.

These are the arguments, the statement of the position of a successful
combination confident in its resources and of victory in the coming
struggle. The justness, the correctness of the doctrines enunciated,
and the wisdom of so doing at this crisis, we do not propose to
criticise; but it is very safe to say that if the prosperity of the
complainants depends upon relief in this direction they may as well
cease producing.

There are too many of them for harmonious and concerted action against
the powerful corporations they complain of; and if they should succeed
in securing equal transportation facilities the prices would still be
regulated by the monopolists, who carry more than four-fifths of the
accumulated stock of the oil regions.

The proposed appeal to Congress to pass some law whereby each producer
can compel railroad companies to carry his produce at regular rates,
amounts to a confession of the desperate straits of the producers
and of their weakness as well; and even if successful, which is most
improbable, would not remedy the deplorable existing state of things.

Still lower rates would fail to give relief, with all the present
avenues of trade filled to repletion and with an increasing output
at the wells. Relief and permanent relief can be found only in the
direction we have before indicated: in the general application of
petroleum and its products to the manufacture of gas for illuminating
and heating purposes, and its substitution for coal in the metallurgic
and other prominent industries of the world.

       *       *       *       *       *




THE LIMIT OF WORK.


In distributing the prizes to workmen at the Paris Exhibition, Louis
Blanc, the leader of the French Republican Socialist party, quoted
approvingly these words of Simonde de Sismondi:

"If the workman were his own master, when he had done in two hours
with the aid of machinery what would have taken him twelve hours to do
without it, he would stop at the end of the two."

M. Blanc had been discussing very eloquently, but also very
fallaciously, the relations of machinery to labor. If men were
properly united in the bonds of association, he said, if the
solidarity of interests were realized, "the happy result of the
application of mechanical power to industry would be equal production,
with less of effort, for all. The discovery of an economic method
would never have the lamentable consequence of robbing men of the work
by which they live. Unfortunately, we are far from this ideal. Under
the empire of that universal antagonism which is the very essence of
the economic constitution of modern societies, and which too often
only profits one man by ruining another, machinery has been employed
to make the rule of the strong weigh more heavily on the weak. There
is not a single mechanical invention which has not been a subject of
anguish and a cause of distress to thousands of fathers of families
from the moment it began to work."

If all this, and much else that M. Blanc alleges, were true, then the
condition of all workingmen to-day should be in every way worse than
that of their fathers, in anti-machinery days. But such is not the
case. There never was a time when the laborer toiled less or enjoyed
more than in these days of machinery; and the laborer's condition is
best where the machinery is best and most used.

A hundred years ago the laborer toiled long, produced little, and
enjoyed less. To-day, thanks to the victories of invention, machinery
does the heaviest of the work; the workman's hours of labor are fewer
than formerly; his wages are greater; and his earnings will buy vastly
more, dollar for dollar, than in any previous age in the world's
history.

What laborer of to-day would be satisfied with the remuneration, the
food, the shelter, the clothing of the laboring classes of one hundred
years ago? The wants of men, as well as their thoughts, are widened by
the process of the suns. And in no section of society have the daily
wants been more markedly increased, or the facilities for gratifying
them either, than among those that live by labor.

"If the workman were his own master, when he had done in two hours
with the aid of machinery what it would have taken him twelve hours to
do without it, he would stop at the end of the two."

So says the theoretical socialist. The practical workman never has,
nor, we believe, ever will, act so foolishly; certainly not until the
limit of man's capacity to enjoy has been reached. When the united
products of manual and mechanical effort fully satisfy the desires of
all men, and leave no margin of want unfilled, then and then only
will men be satisfied with the reduction of effort demanded by the
socialists. Until then the larger part of every increase in production
by mechanical improvements will go to swell the volume of good things
for human use and enjoyment. Our machinery enables our thousands of
busy workers to accomplish what millions could not have done years
ago, and a very large part of the aggregate increase of product
comes back to them in conveniences and luxuries surpassing those
the wealthiest could enjoy were machinery not employed, or were it
employed, as the socialist advocates, without increasing the aggregate
of production. The laziness of the savage and the advantages of
civilization are incompatible. The chief merit of machinery lies in
its enabling us to multiply constantly the scope and variety of our
enjoyments without a corresponding increase of toil.

       *       *       *       *       *




IRIDESCENT GLASS.


Ornamental glassware in many styles, tinted with the glowing colors
of the rainbow, is now making its appearance in the shop windows
of Broadway and Fifth Avenue. This is one of those brilliant little
achievements of science that delights the eye and pleases the
imagination. To produce the colors, the glass, while in a heated
state, is subjected to the vapor of chloride of tin. Shades of more or
less depth or intensity are imparted by adding to the tin chloride a
little nitrate of strontium or barium.

       *       *       *       *       *




RAILS AND RAILWAY ACCIDENTS--NEW YORK ACADEMY OF SCIENCES.


A meeting of the Section of Physics, New York Academy of Sciences,
was held November 25, 1878. President J. S. Newberry in the chair.
Numerous publications of learned societies were received and
acknowledged. Professor Newberry read a letter from Professor Agassiz
stating that sea lilies, which had hitherto been very rare--a single
specimen bringing as much as fifty dollars--have been found in some
numbers by dredging in the Gulf of Mexico. Their colors are white,
pink, and yellow. Professor Newberry also exhibited specimens of
garnet from California, lamellar quartz from North Carolina, sharks'
teeth belonging to the eocene and miocene tertiary ages from the
phosphate beds of South Carolina, and a number of shells.

Professor Thomas Egleston then addressed the Academy on the subject of
"The Structure of Rails as Affecting Railway Accidents."

The destruction of rails is due to three causes. 1. Defects in the
manufacture; 2. Improper mechanical or chemical composition; and 3.
Physical changes.

A very large number of rails are annually made which should never be
put in any track. Their defects are often imperceptible to the naked
eye, but they very soon begin to break. Statistics show that the
breakage from defects in making increase until they have been used
18 months; then it decreases to zero, and after that rails break from
different causes. In France, breakage usually begins in December,
reaches its maximum in January, and becomes normal in April. As a more
intense cold would be necessary to explain such breakage than that
which is felt in that climate, the cause must be sought in the
stiffness and inelasticity of the frozen road bed. The impact of
the locomotive is then apt to break the rail, very much on the same
principle that is taken advantage of in breaking them up for the
manufacture of smaller objects. A nick is made somewhere, and the
workman then strikes a blow with a hammer at a point between the nick
and the place where the rail is supported. This will sever the rail at
the nicked place. Sometimes more than a second intervenes between the
blow and the fracture. Now, whenever holes are punched in rails for
the fish plates, flaws are apt to radiate from them; and if these
flaws are not planed or filed out, they may cause the rail to break,
just as the nicks above mentioned. Such rails have been known to last
no longer than 18 months, and some have actually broken on the way
from the manufacturer to their destination. There are establishments
in this country and in Europe where they "doctor" such rails by
filling up the flaws with a mixture of iron filings, sal ammoniac, and
some adhesive substance. Beware of them; a poor cheap rail is dear
at any price. The French government stipulates in its contracts for
rails, that flaws shall be planed, drilled, or filed out; that the
rails shall not be allowed to drop on the ground, but shall be carried
by men and slid down. The Lyons railroad does not pay for its rails
until 15,000 trains have passed over them.

By imperfect mechanical composition is meant imperfect union of the
parts of rails. Steel heads are welded to the rest of the rail in a
variety of ways, and this welding is necessarily imperfect. A number
of sections of rails etched with acid plainly showed this want of
homogeneity, as did likewise prints taken from the etched surfaces.
Before such rails have lost weight appreciably, they are used up by
the constant rolling they undergo. The advantage of a steel rail is
its homogeneity, but a good iron rail, such as those made under the
direction of the speaker, for the Reading Railroad Company, is likely
to prove better than one of poor steel. The life of a steel rail
is chiefly affected by the temperature at which it is rolled and
annealed. It ought not to wear off more than 1 mm. for 20,000,000
tons of traffic, and is usually calculated to wear 10 mm. before it is
taken up. In other words, it would last about 20 years on roads doing
as much business as the New York Central. It is, however, unlikely
that our steel rails will stand more than half this amount of traffic.

The effects of chemical composition are but little understood. Some
of the purest irons have turned out utterly worthless. Apparently the
absolute quantities of carbon, silicon, aluminum, phosphorus, etc.,
present are not of so much importance as their relative proportion.
One specimen containing carbon 0.16, silicon 0.08, and phosphorus
0.012, could be bent double when cold, while another, containing
carbon 0.58, silicon 0.56, and phosphorus 0.011 broke at once.

The physical tests for tensile and torsional strength, usually made on
a portion cut out of the head of the rail, are not sufficient, because
the flaws before spoken of exist mostly in the flange of the rail, and
fracture usually begins there.

The effect of