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SCIENTIFIC AMERICAN SUPPLEMENT NO. 286




NEW YORK, JUNE 25, 1881

Scientific American Supplement. Vol. XI, No. 286.

Scientific American established 1845

Scientific American Supplement, $5 a year.

Scientific American and Supplement, $7 a year.


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     TABLE OF CONTENTS.

I.   ENGINEERING AND MECHANICS.--One Thousand Horse Power Corliss Engine.
     5 figures, to scale, illustrating the construction of the new one
     thousand horse power Corliss engine, by Hitch, Hargreaves & Co.

     Opening of the New Workshop of the Stevens Institute of Technology.
     Speech of Prof. R.W. Raymond, speech of Mr. Horatio Allen.

     Light Steam Engine for Aeronautical Purposes. Constructed for Capt.
     Mojoisky, of the Russian Navy.

     Complete Prevention of Incrustation in Boilers. Arrangement for
     purifying boiler water with lime and carbonate of soda.--The
     purification of the water.--Examination of the purified
     water.--Results of water purification.

     Eddystone Lighthouse. Progress of the work.

     Rolling Mill for Making Corrugated Iron. 1 figure. The new mill of
     Schultz, Knaudt & Co., of Essen, Germany.

     Railway Turntable in the Time of Louis XIV. 1 figure. Pleasure car.
     Railway and turntable at Mary-le-Roy Chateau, France, in 1714.

     New Signal Wire Compensator. Communication from A. Lyle, describing
     compensators in use on the Nizam State Railway, East India.

     Tangye's Hydraulic Hoist. 2 figures.

     Power Loom for Delicate Fabrics. 1 figure.

     How Veneering is Made.

II.  TECHNOLOGY AND CHEMISTRY.--The Constituent Parts of Leather. The
     composition of different leathers exhibited at the Paris
     Exhibition.--Amount of leather produced by different tonnages of 100
     pounds of hides.--Percentage of tannin absorbed under different
     methods of tanning.--Amounts of gelatine and tannin in leather of
     different tonnages, etc.

     Progress in American Pottery.

     Photographic Notes.--Mr. Waruerke's New Discovery.--Method of
     converting negatives directly into positives.--Experiments of Capt.
     Bing on the sensitiveness of coal oil--Bitumen plates.--Method of
     topographic engraving. By Commandant DE LA NOE.--Succinate of Iron
     Developer.--Method of making friable hydro-cellulose.

     Photo-Tracings in Black and Color.

     Dyeing Reds with Artificial Alizarin. By M. MAURICE PRUD'HOMME.

III. ELECTRICITY, PHYSICAL SCIENCE, ETC.--On Faure's Secondary Battery.

     Physical Science in Our Common Schools.--An exceptionally strong
     argument for the teaching of physical science by the experimental
     method in elementary schools, with an outline of the method and the
     results of such teaching.

     On the Law of Avogadro and Ampere. By E. VOGEL.

IV.  GEOGRAPHY, GEOLOGY, ETC.--Petroleum and Coal in Venezuela.

     Geographical Society of the Pacific.

     The Behring's Straits Currents.--Proofs of their existence.

     Experimental Geology.--Artificial production of calcareous pisolites
     and oolites.--On crystals of anhydrous lime.--4 figures.

V.   NATURAL HISTORY, ETC.--Coccidae. By Dr. H. BEHR.--An important paper
     read before the California Academy of Sciences.--The marvelous
     fecundity of scale bugs.--Their uses.--Their ravages.--Methods of
     destroying them.

     Agricultural Items.

     Timber Trees.

     Blood Rains.

VI.  MEDICINE AND HYGIENE.--Medical Uses of Figs.

     Topical Medication in Phthisis.

VII. ARCHITECTURE, ETC.--Suggestions in Architecture.--Large
     illustration.--The New High School for Girls, Oxford, England.

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PETROLEUM AND COAL IN VENEZUELA.


MR. E. H. PLUMACHER, U. S. Consul at Maracaibo, sends to the State
Department the following information touching the wealth of coal and
petroleum probable in Venezuela:

The asphalt mines and petroleum fountains are most abundant in that part
of the country lying between the River Zulia and the River Catatumbo,
and the Cordilleras. The wonderful sand-bank is about seven kilometers
from the confluence of the Rivers Tara and Sardinarte. It is ten meters
high and thirty meters long. On its surface can be seen several round
holes, out of which rises the petroleum and water with a noise like that
made by steam vessels when blowing off steam, and above there ascends a
column of vapor. There is a dense forest around this sand-bank, and the
place has been called "El Inferno." Dr. Edward McGregor visited the
sand-bank, and reported to the Government that by experiment he had
ascertained that one of the fountains spurted petroleum and water at the
rate of 240 gallons per hour. Mr. Plumacher says that the petroleum is
of very good quality, its density being that which the British market
requires in petroleum imported from the United States. The river, up to
the junction of the Tara and Sardinarte, is navigable during the entire
year for flat-bottomed craft of forty or fifty tons.

Mr. Plumacher has been unable to discover that there are any deposits
of asphalt or petroleum in the upper part of the Department of Colon,
beyond the Zulia, but he has been told that the valleys of Cucuta and
the territories of the State of Tachira abound in coal mines. There are
coal mines near San Antonia, in a ravine called "La Carbonera," and
these supply coal for the smiths' forges in that place. Coal and asphalt
are also found in large quantities in the Department of Sucre. Mr.
Plumacher has seen, while residing in the State of Zulia, but one true
specimen of "lignite," which was given to him by a rich land-owner,
who is a Spanish subject. In the section where it was found there are
several fountains of a peculiar substance. It is a black liquid, of
little density, strongly impregnated with carbonic acid which it
transmits to the water which invariably accompanies it. Deposits of this
substance are found at the foot of the spurs of the Cordilleras, and are
believed to indicate the presence of great deposits of anthracite.

There are many petroleum wells of inferior quality between Escuque and
Bettijoque, in the town of Columbia. Laborers gather the petroleum in
handkerchiefs. After these become saturated, the oil is pressed out by
wringing. It is burned in the houses of the poor. The people thought, in
1824, that it was a substance unknown elsewhere, and they called it
the "oil of Columbia." At that time they hoped to establish a valuable
industry by working it, and they sent to England, France, and this
country samples which attracted much attention. But in those days no
method of refining the crude oil had been discovered, and therefore
these efforts to introduce petroleum to the world soon failed.

The plains of Ceniza abound in asphalt and petroleum. There is a large
lake of these substances about twelve kilometers east of St. Timoteo,
and from it some asphalt is taken to Maracaibo. Many deposits of asphalt
are found between these plains and the River Mene. The largest is that
of Cienega de Mene, which is shallow. At the bottom lies a compact
bed of asphalt, which is not used at present, except for painting
the bottoms of vessels to keep off the barnacles. There are wells of
petroleum in the State of Falcon.

Mr. Plumacher says that all the samples of coal submitted to him in
Venezuela for examination, with the exception of the "lignite" before
mentioned, were, in his opinion, asphalt in various degrees of
condensation. The sample which came from Tule he ranks with the coals
of the best quality. He believes that the innumerable fountains and
deposits of petroleum, bitumen, and asphalt that are apparent on the
surface of the region around Lake Maracaibo are proof of the existence
below of immense deposits of coal. These deposits have not been
uncovered because the territory remains for the most part as wild as it
was at the conquest.

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ONE THOUSAND HORSE-POWER CORLISS ENGINE.


[Illustration: FIG. 1.

DIA. OF CYLINDER = 40''
STROKE = 10 ft.
REVS = 41
SCALE OF DIAGRAMS 40 LBS = 1 INCH

FIG. 2.]

We illustrate one of the largest Corliss engines ever constructed. It is
of the single cylinder, horizontal, condensing type, with one cylinder
40 inches diameter, and 10 feet stroke, and makes forty-five revolutions
per minute, corresponding to a piston speed of 900 feet per minute. At
mid stroke the velocity of the piston is 1,402 feet per minute nearly,
and its energy in foot pounds amounts to about 8.6 times its weight.
The cylinder is steam jacketed on the body and ends, and is fitted with
Corliss valves and Inglis & Spencer's automatic Corliss valve expansion
gear. Referring to the general drawing of the engine, it will be seen
that the cylinder is bolted directly to the end of the massive cast iron
frame, and the piston coupled direct to the crank by the steel piston
rod and crosshead and the connecting rod. The connecting rod is 28
feet long center to center, and 12 inches diameter at the middle. The
crankshaft is made of forged Bolton steel, and is 21 inches diameter at
the part where the fly-wheel is carried. The fly driving wheel is 35
feet in diameter, and grooved for twenty-seven ropes, which transmit the
power direct to the various line shafts in the mill. The rope grooves
are made on Hick, Hargreaves & Co.'s standard pattern of deep groove,
and the wheel, which is built up, is constructed on their improved plan
with separate arms and boss, and twelve segments in the rim with joints
planed to the true angle by a special machine designed and made by
themselves. The weight of the fly-wheel is about 60 tons. The condensing
apparatus is arranged below, so that there is complete drainage from the
cylinder to the condenser. The air pump, which is 36 inches diameter and
2 feet 6 inches stroke, is a vertical pump worked by wrought iron
plate levers and two