eBay

Good condition. Shipped priority mail.

Fatima Gypsy cigarette ad on back cover.

Upper engraving represents submarines entering the lock at Gatun. Lower engraving shows submarines submerged and resting on the cradles.

DRYDOCKING IN PANAMA CANAL LOCKS.-[See page 328.]

----------- 2 -----------

THE present year will go down in the annals of

yacht racing as one of the most famous in the

history of this noble sport.

The coming again

to our shores of the indomitable Lipton, this time with

the fourth "Shamrock," has resulted in the construction'

of three defending yachts, one by the veteran Herreshoff,

another by his most able American competitor, Gardner,

and a third by one of the most promising of our younger

designers, Owens.

Particular interest attaches to this year's series of

contests, because of the fact that they will be held under

new rule of measurement, which discourages the

building of the extreme and almost freakish type of

yacht with which the public was made familiar in the

last series of "America" cup contests. The old rule en-

couraged the construction of a yacht of extreme beam,

draught, and over-all length, with a flat floor and full

énds, and carrying an enormous spread of sail.

new rule governing this year's contests encourages a

return to a more wholesome form, with a fuller and

deeper body and sharper ends-a type which, after the

races are over, is still serviceable for cruising because

of its greater head room and its easier motion in a sea-

Furthermore, the more limited draught enables

the yacht to enter harbors and cruise in waters which

are inaccessible to the older type. When it is remem-

bered that these manifest advantages are secured with-

out any sacrifice of speed, the all-round advantages of

The

way.

the new rule over the old will be manifest.

In Nicholson, one of the younger designers, the chal-

lenger has at his disposal the genius of the most suc-

cessful yacht designer, probably, in Great Britain.

"Shamrock IV" will also have the advantage of being

absolutely in charge of the most successful amateur

yachtsman to be found in the British Isles.

Mental Acrobatics

HAT perfection in the solving of scientific prob-

lems is an art to be acquired by training, prac-

tice, and experience is so obvious a truth as to

require no emphasis and to invite no contradiction.

Not so obvious is the fact that in the selection of

problems for inquiry, in the mere asking of questions,

much depends on the judgment and common sense of

the inquirer. Indeed, it has been said that the great

man in science is recognized not so much by the means

he employs to attain his ends, as by the purposes toward

which he bends his efforts.

tutod

thet

----------- 3 -----------

greater than 500 miles.

Electric Dock Equipment.-Quite an extensive electric

outfit is used at the new docks on the Spree, at Berlin.

The docks are well laid out for handling grain, as well as

for receiving supplies of benzine in underground tanks,

coal, brick and other freight, and the port is connected by

tracks with the railroad. No less than 37 electric motors

are used for the ten main cranes, while 28 motors serve for

various conveyers for the grain docks. Numerous other

cranes besides winches and elevators take upward of 20

motors. The whole is a model plant. Some 200 railroad

cars are accommodated in the dock quarters, and most

of the material is handled by electric devices so as to

assure a rapid service.

Alternating Arc in Mercury Vapor.-It has commonly

been supposed that it is impossible to maintain an alter-

nating arc in mercury vapor, for low frequencies and

moderate voltages. In a paper read at the Paris Academy

of Sciences, it was shown that this can be done. The

quartz tube is full of mercury and ends in two reservoirs

in communication with the atmosphere. Placed in series

is a self-induction enabling the short circuit current to

be reduced to about 2½ amperes. The arc is started by

breaking the column in the middle by causing the mer-

cury to bubble. A true alternating are is established, the

two alternations being separated by a period of extinction

of about one thousandth of a second.

German Army Searchlight.-The German army is

making use of a type of field electric searchlight which

can be raised to quite a distance above the ground by

the use of a telescopic tubular pole, this being made in

four sections. By means of a hand winch, the tube is

extended to the desired height, so that the beam can be-

directed to advantage. The apparatus is mounted on a

two-wheel truck which is coupled to a second truck with

driver's seat so as to make a four-wheel wagon. On the

ground, the searchlight truck is uncoupled, and set at

the proper point. The mast portion is folded down flat

against the framework when not in use. Current comes

from a dynamo group on a special wagon.

Effect of the Eclipse on Radio-telegraphy.-The

British Association for the Advancement of Science has

issued a bulletin calling attention to the exceptional op-

portunities that will be afforded by the total eclipse of

the sun on August 21st for studying the effect of light

and darkness upon radiotelegraphy. The eclipse will be

total along a strip extending from Greenland across Nor-

way, Sweden, Russia and Persia to the mouths of the

Indus. In Russia, the duration of totality will be a little

mnin noints

----------- 4 -----------

Treating Yeast with Ozone.-A curious commercial

application of ozone has just been developed in the brew-

ing industry. Samples of brewers' yeast treated with

ozone for five minutes show greater fermenting power

than untreated yeast. During the first day or two, there

is no gain, but after that ozonized yeast exhibits fer-

mentative power markedly in excess of untreated yeast.

The benefit comes from the inhibitive action of ozone on

objectionable organisms, and also because the weaker

yeast cells are eliminated and the stronger ones stimulated

in fermentative power.

over-production of yeast cells is a great source of loss

which will doubtless be lessened by ozonization.

In the brewing industry, the

The Lost Russian Arctic Expeditions.-The Russian

government has at last decided to make a search for the

missing expeditions of Sedov, Russanov, and Brussilov,

and has bought two Norwegian vessels, the "Hertha"

and the "Eclipse," for this purpose. The "Hertha," with

a Russian crew,

will

in quest of Capt. Sedov's expedi-

tion, which is supposed to have sailed last August from

the north coast of Nova Zembla for Franz Josef Land,

and has not since been heard from. The "Eclipse," with

a Norwegian crew, and under the command of the

veteran explorer Capt. Otto Sverdrup, will proceed to

the Kara Sea in hope of locating the expeditions of

Brussilov and Russanov, both of which have been missing

since the autumn of 1912. The former set out to attempt

the Northeast Passage, while the latter was last heard

from when en route from Spitzbergen to Nova Zembla.

The rescue ships are to sail from Christiania, June 24th.

Capt. Amundsen's North Polar Expedition, which, as

originally planned, was to have sailed in the summer of

1913, and was postponed for a year in order to give the

scientific staff more time for preliminary studies and

training, has now again been postponed for a year; this

time because it appears that the "Fram," the vessel in

which the expedition is to sail, cannot reach San Francisco

in time for an early start from that port. Last year, the

little vessel sailed from Buenos Ayres to Colon, in the

expectation of proceeding thence via the Panama Canal;

on account of the delay in the opening of the latter, this

route was finally abandoned, and the "Fram" started on

the long journey around the continent in which she is

now engaged.

tion will be turned to advantage, especially in giving the

explorers time to become expert in the use of aeroplanes,

three of which are to be included in the equipment of the

expedition,

The further postponement of the expedi-

----------- 5 -----------

825

Astronomy

The Duration of the Sun.-Adopting the well-known

hypothesis of Helmholtz, which attributes the production

of the heat emitted by the sun to its contraction, an idea

can be formed of the sun's duration. If one gives to the

sun a coefficient of expansion intermediate between that

of mercury and that of gas, one arrives at the conclusion

that it has taken one to three millions of years for the

sun to contract to its present radius; in particular, it

would have taken 10,000 years to contract from infinity

to a radius twice its present radius. Finally, the sun

will take 200 millions of years to contract from its present

radius to half that radius, and even then its temperature

at the surface will be 3,000 degrees.

Earth-Shine on the Moon.-When the sun has dis-

appeared beneath the horizon and we no longer re-

ceive its rays direct, it also happens that its light con-

tinues to reach us, indirectly and feebly, reflected by

the whole or part of the disk of the moon.

when a portion of the lunar disk is not illuminated

directly by the sun, it happens that it is feebly illumi-

nated by the earth-shine; that is to say, by the reflection

that those portions of the terrestrial surface which are

at that moment exposed to the sun.

has endeavored to determine the brightness of the light

received in this way by the moon and has measured the

intensity of this light compared with the intensity of

those parts of the lunar disk which are illuminated

directly by the sun.

on the moon is about 1,600 times feebler than the mean

brightness of those portions illuminated by the sun a

little before the first quarter.

Inversely,

Mr. F. W. Very

The result is that the earth-shine

Distance of the New Star in Gemini.-In the spring

of 1912, considerable interest was excited by the sudden

appearance of a brilliant star which became visible to

the naked eye during some weeks in March and April.

After May it was no longer visible except in powerful

telescopes. Mr. Slocum has attempted to measure the

parallax of this star, and hence to deduce its distance

from us.

Parallax is a measure of the change of per-

spective a mo ving object presents when regarded from

two different positions. Advantage is taken of the revolu-

tion of the earth in its orbit, and measurements are made

at intervals of six months. Mr. Slocum, with the great

40-inch refractor at the Yerkes Observatory, has taken

fifteen photographs 'of the new star at three different

periods of six months. Six comparison stars were selected

as near the Nova as possible, and distributed approxi-

mately symmetrically round it.

results shows that the Nova is about 296 light years

A discussion of the

away, so that the sudden blaze of 1912 corresponded to

some catastrophe which occurred in the beginning of the

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SCIENTIFIC AMERICAN

Moving Pictures Without a Screen

A Remarkable Development in Kinematography

By the English Correspondent of the SCIENTIFIC AMERICAN

----------- 7 -----------

OME five years ago a German experi-

menter, Herr Messter, as a result of some

particular investigations, discovered that if

moving pictures were projected by reflection

in a certain manner, the stage could be set

with scenery and properties, as for a regu-

lar play, with the result that the usual white

screen could be eliminated, and that the

photographic figures could be moved about

within a certain area in such a manner as to

convey the illusion that living performers

were seen instead of photographic reproduc-

He pursued his experiments, but was

faced with the initial difficulty that only

small figures could be projected, and this fact

tended to destroy the illusion, since to main-

tain the latter, life-size portrayal of the per-

tions.

formers was imperative.

Another complex-

ity which troubled him was the destruction

of the coloring qualities owing to the high

light necessary.

This latter problem was

overcome by utilizing pierrots and clowns, in

which only black and white dress and make-

up were required. Such a limitation was a

handicap, but, nevertheless, when such pic-

tures were shown, considerable interest and

wonder as to how the effects were obtained,

were aroused. The fact that the figures were

dwarfish, and yet apparently endowed with

life, enhanced the mysterious effect.

patient experimenting the inventor at last over

came the latter deficiency, and having succeede

in getting his figures life size, public exhibition

of "Alabaster," as it was called, were given in

Vienna with great success.

The absence of the

familiar white screen proved an irresistible at-

traction.

At the Scala Theater in London the

pictures, upon their presentation, proved an in-

stantaneous success.

The explanation of the mystery is exceedingly

simple. Kinoplastikon is no more nor less than

a revival of the famous "Pepper's Ghost" idea,

adapted to the kinematograph. Singing and talk-

ing effects are obtained by electrically synchron-

izing a talking machine with the acting.

The accompanying diagram explains ex-

----------- 8 -----------

SCIENTIFIC AMERICAN

The Problem of Our Navy

VIII. -Mobilization and a Naval Reserve

By the Editor

----------- 9 -----------

ODERN wars begin with all the surprise and vio-

lent shock of an explosion of dynamite-as witness

the night attack by the Japanese destroyers at Port

Arthur, which, even before the declaration of war,

placed the Russian Pacific fleet out of commission and

gave to Japan the command of the sea.

The striking of the first telling blow and the ability

to follow it up are posssible only when the belligerent,

having set in motion a carefully prepared plan of

mobilization, is able swiftly to concentrate the whole

of his naval and military forces in the theater of war

-as witness the fact that following immediately upon

the Port Arthur attack, Japan transported to the main-

land an army of 100,000 men in four days time.

Наd Japan followed our оиn policy of unprepared-

ness, had she possessed no plan of mobilization, that is

to say, had she left the work of organizing an auxiliary

fleet to be done after war was actually upon her, as we

did in the Spanish war, months of valuable time would

have been lost, Russia would have been able to concen-

trate an overwhelming army in Korea and Manchuria,

and the defeat of Japan would have been inevitable.

Mobilization is defined in the Dictionnaire Militaire

as "the passage from a peace to a war footing, the

period during which a 'navy' should be provided with

everything which is necessary for it to go into a cam-

paign and at once begin active operations."

The same authority goes on to say:

important that this period should be as short as pos-

sible, for upon its efficient and complete achievement

often depends the fate of the first encounters.

fore, each nation has spared no pains to foresee in all

their details the complex operations necessary to be

carried out during this period of transition, so that

"It is naturally

There-

when the time arrives, they may be executed without

disorder, omissions or loss of time."

Have we any such elaborate system of mobilization?

The last attempted mobilization occurred in

the

North River, New York, in October, 1911, when there

were assembled no less than 127 ships, including 31

battleships-an imposing array of naval materiel, which,

if the individual ships had been fully manned and pro-

visioned, and replete with full supplies of coal and

ammunition, and if the fleet as a whole had included

11 the auxiliaries necessary to enable it to keep the

ould have been a most formidable fighting force.

t were the facts?

Ins in full commission were more or less

officers and men, in order to furnish

t in handling the ships that were

----------- 10 -----------

Drydocking in Canal Locks

By C. W. Fisher, Naval Constructor, United States

Navy

ON December 12th, 1913, five submarines of the

United States Navy with their mother ship or

tender, the "Severn," arrived at Cristobal, Canal Zone.

These boats are known as "C-1," “C-2," “C-3," "C-4,"

They were tied up alongside their mother

and "C-5."

ship, upon which the crews and officers live and mess,

at one of the new concrete piers built by the Panama

Railroad Company. This unique flotilla attracted great

interest on account of its peculiar appearance, and its

daily exercises in the harbor of Colon, where the small

boats dived and maneuvered.

After four months of this duty it was found neces-

sary to place the five submarines in drydock for the

usual overhauling, testing and cleaning bottoms from

the accumulation of barnacles and other marine growth.

The small drydock at Mount Hope, near Cristobal,

which was built many years ago by the French, and

which is supposed to serve for all docking purposes

until the big docks now under construction at Balboa

are completed, about eighteen months hence, was un-

fortunately not available, on account of its being in

constant use repairing the dredges at work on the big

slide at Culebra. It was, therefore, necessary to devise

some other scheme for docking these vessels, and it was

decided to utilize one of the great locks at Gatun for

this purpose.

Accordingly, on March 8th, 1914, the old "Severn,"

well known to many a midshipman, having served for

years as a practice ship for the Naval Academy, now

divested of her sails and machinery, was towed up to

Gatun, accompanied by the five little submarines under

their own power.

When the interesting fact became known that the

very first navy vessel of any nation was about to pass

through the locks of the Panama Canal and to enter

Gatun Lake, large numbers of spectators gathereu

upon the walls of Gatun locks to witness this event, and

on March 8th, 1914, the "Severn" was locked through

End tied up to the approach wall of the Gatun locks m

tun Lake, thus recording an important event in the

of the Panama Canal. On the following morn-

9th, the submarines were locked through

of Gatun and drydocked in the upper

gar-shaped, and in order to land

----------- 11 -----------

Aviation in the British Army

N important statement was made by Col. Seely

A recently with regard to the progress of aviation in

the British army.

The present position of Great Britain may be sum-

marized as follows:

1. The army has transferred its airships-there never

were many-to the navy.

2. The army, in future, will concentrate on aero-

planes, which are being improved every day.

How many, then, of these all-necessary aeroplanes

are possessed by the British army? The answer is 161,

of which 100 were added during the last twelve months.

There are to be eight squadrons, complete in men and

machines, by the end of the coming financial year, and

the total number required will be 250-50 for the Cen-

tral Flying School, and 200 for the eight squadrons,

twenty-five to each.

mitted, if you want ten machines to be ready at a given

moment, you must have twenty to draw on. Each aero-

plane, in a word, must have a spare machine as its

fellow, and the two can only count as one, so delicate

are these machines, with so many things to go wrong

and to give way.

Col. Seely also stated that he was providing for a

large increase in the provision of spare parts, and for

the creation of an Inspection Department. He spoke of

his anxiety to do anything to lessen the risk of flying,

and surprised the House of Commons by saying that

there had only been six days in the year-barring Sat-

urdays and Sundays-on which there had been no army

flights; that there had not been a fatal accident to offi-

cer or man belonging to the military wing proper; and

not a single breakage of any main part in the air.

The newest aeroplanes have an average speed of from

But, as Col. Seely frankly ad-

sixty to sixty-six miles an hour.

The Current Supplement

N this week's issue of the SCIENTIFIC AMERICAN SUP-

PLEMENT L. D. Allen writes on the manufacture and

use of bearing metals.-E. E. Fournier d'Albe in an arti-

cle "The Radiation Problem" gives a general survey of

modern theories of radiation, with special reference to

the "quantum" or "atomic" theory of light energy.-J.

Whitman Bailey contributes an article entitled "A Com-

parison of Rivers."-The special organs by which ani-

mals are enabled to maintain their equilibrium and

sense of the vertical direction form the subject of an

article by W. Baunacke.-In an article on the wasteful-

----------- 12 -----------

în the SCIENTIFIC AMERICAN of March 21st, 1914, you

published an article of mine under the title "The Big-

gest Bird that Ever Lived." The title which I gave the

article was "The Largest Fossil Bird Known."

your attention to this difference in titles because I do

I call

not wish to assume the responsibility of calling the ex-

tinct bird that I described "The Biggest Bird that Ever

Lived."

Washington, D. C.

R. W. SCHUFELDT.

Increasing Motor Output

To the Editor of the SCIENTIFIC AMERICAN :

In the SCIENTIFIC AMERICAN of March 14th, 1914,

page 227, you published, under the heading "Electricity,"

a note calling attention to a method to increase the

amount of power which a given electric motor can be

called upon to furnish, and you attribute the method de-

scribed to Messrs. Brown, Boveri & Co.

Permit us to state that the invention in question must

be credited to Maurice Leblanc, and that it is covered

in the United States in particular by two patents,

815,356 and 815,357, granted March 20th, 1906.

patents were assigned to Mr. Westinghouse.

Messrs. Brown, Boveri & Co. are our licensees.

These

SOCIÉTÉ ANONYME WESTINGHOUSE.

Scientific Photographs Wanted for the Royal

Photographic Society Exhibition

To the Editor of the SCIENTIFIC AMERICAN :

The Royal Photographic Society of Great Britain is

holding its fifty-ninth annual exhibition in August

and September of this year. This is the most repre-

sentative exhibition of photographic work in the world,

and the Society is anxious to make it more interna-

tional in character. It is very desirable that American

scientific photography should be fully represented at

the exhibition, and in order to enable this to be done

with less work to the exhibitor, I have arranged to col-

lect and forward American work intended for the scien-

tific section.

This work should consist of prints showing the use

of photography for scientific purposes, and its applica-

tion to spectroscopy, astronomy, radiography, biology,

etc. Photographs should reach me not later than Fri-

day, July 10th.

framed.

They should be mounted, but not

I should be glad if any worker who is able to send

photographs will communicate with me as soon as pos-

sible so that I might arrange for the receiving and entry

C. E. KENNETH MEES.

of the exhibit.

Research Laboratory, Kodak Park, Rochester, N. Y.

----------- 13 -----------

S30

SCIENTIFICAMLIIorin

Forge furnace heating heavy work for the hammer.

Forge furnace burning a blast of coal dust. A great saving of fuel.

Powdered Coal for Fuel

Burning Coal Dust in Jets Like Oil

o By Harry N. Holmes

----------- 14 -----------

HE use of powdered coal as a fuel has been devel-

oped to successful practice. It possesses all the ad-

vantages of burning an oil spray and the additional one

of greater economy.

bustion chamber intimately mixed with a blast of air

and is there completely burned with little or no smoke.

Like oil, it is blown into the com-

The comparison of values is interesting. Assuming

that there are 19,000 British thermal units in a pound

of oil and an average of 13,500 British thermal units in

a pound of bituminous coal, and that gas producers will

give 85 per cent efficiency, the following values are

Oil at 44 cents per gallon, 28,600 British

thermal units for 1 cent; producer gas from coal at

deduced :

$3.10 per ton, 69,673 British thermal units for 1 cent;

powdered coal, slack, at $2.75, 98,181 British thermal

units for 1 cent.

To further this economy in operation a minimum of

attention is required, for the best equipment is almost

automatic in many details.

Oil stoking requires little

attention, and the two operations are similar in this as

in other respects. The absence of smoke is the natural

result of the perfect combustion, as every minute par-

ticle of coal dust is completely burned in a proper in-

stallation. The intense heat obtainable by this coal dust

jet will develop many special applications. One of the

greatest advantages of this method of furnace firing is

its adaptability to any grade of fuel, even coal that

has no value on the grate bars. Anthracite, bitu-

minous, lignite, coke breeze, all are grist to this

Experts consider that coal with

sort of mill.

45 per cent ash has no steam raising value what-

ever when burned in the old way, but Barmhurst

has obtained profitable results with coal of 52

per cent ash in a coal dust jet. This method

of firing makes possible a tremendous develop-

ment of the low-grade coals of the West.

There are four simple requirements which ab-

solutely must be obeyed :

First-The coal must be dried so that it con-

tains not over one per cent of moisture.

Second-The coal must be pulverized to a

high degree of fineness.

Third-It must be blown into a chamber hot

enough to cause instant deflagration.

Fourth-It must be supplied with air suffi-

cient to yield the oxygen necessary to burn the

carbon of the coal at once to carbon dioxide:

Drying the coal is essential for two reasons.

Coal containing much more than one per cent

moisture is not easily ground to a fine powder.

Furthermore if this moisture were not removed

----------- 15 -----------

The Taxicab Service of New York City

By Harry Chapin Plummer

RULY magnificent distances are those compassed

by Father Knickerbocker in that vehicle which is

so characteristic of the twentieth century-the taxicab.

There are three thousand of those restless, snorting,

erratic conveyances in service in the streets of Greater

New York, and, barring a limited area in the Borough

of Brooklyn and isolated sections of the Bronx and

Queens, they are mostly all concentrated in the district

(Concluded on page 336.)

----------- 16 -----------

AGO

A LIGHT FOR AIR CRAFT WHI CH

IS THE EQUIVALENT OF A MARINE

THE LAMP RECEI VES CURRENT

NAVIGATING LIGHT.

FROM A STORAGE BATTERY.

Aeroplane lamps with lights of different colors, for showing their path and signaling their position when flying at night.

Aeroplane Lamps

A Light That Shows "Port'" and "Starboard " and Also Throws White Beams Forward and to the Rear

By Dr. Alfred Gradenwitz

----------- 17 -----------

DIRIGIBLES are generally equipped with lamps

fixed to the right and left, respectively, which, like

those of ships on rivers or at sea, indicate the direction

of traveling by red and green lights. In a similar man-

ner, it would be desirable to fit aeroplanes with two

lamps giving out lights of different colors, thus enabling

their position on the ground and their path through the

air to be signaled and collision with other air craft to

be prevented.

A manufacturer in Berlin has designed a special

aeroplane lantern which would seem to comply with

all requirements to be satisfied by such lamps.

constituting no material extra load on the aeroplane

and needing, under way, no attendance or supervision,

it allows its position or direction of flight to be ascer-

tained with all desirable accuracy.

While

This aeroplane lamp comprises a lantern casing in-

side of which there is arranged a 10 candle-power metal

filament lamp whose light is so reinforced by an annu-

lar lens, that the luminous intensity actually given out

amounts to about 40 Hefner candles.

The lamp is

plainly visible, even in foggy weather, to a distance of

Since the light is given out uni-

formly on all sides, the lamp is surrounded by a lumin-

ous ring. In order also to signal the direction of flight

by means of this lamp, red and green glasses are so

arranged in the interior of the annular lens that the

forward portion of the luminous ring (about 10 degrees)

appears white, whereas the adjoining part to the right

(about 110 degrees) is colored green and the left-hand

The rearward portion be-

about three miles.

part of equal length, red.

tween the red and the green parts (about 130 degrees)

This simple arrange-

again gives out a white light.

ment of the optical system enables any aeroplane

equipped with the lamp to be sighted (and its direc-

tion of flight ascertained) at sufficient distance, the ob-

server seeing more or less of the red or the green

light beside the white.

The metal filament lamp is so designed that heavy

shocks, as produced on landing, will exert no influence

on it.

Moreover, its fitting is carried by a substantial

spring, damping any jerks.

The incandescent lamp is fed from an Edison accumu-

lator, arranged close to the driver's or observer's' seat,

which complies with all requirements of the case.

Re-

plenishing with potash is only necessary every eight

to twelve months, according to the actual strain on

Refilling is effected exclusively with

Inclinations up to 45 degrees and

the accumulator.

pure distilled water.

----------- 18 -----------

The first aeroplane in Jerusalem.

Motorcycle fitted with a revolving cylinder motor.

An armored motor car.

PUNA

----------- 19 -----------

Telt it.

First Aeroplane in Jerusalem

DURING the last few months the aero-

plane has made its appearance in

many strange places, not the least among

these being the ancient city of Jerusalem.

It was during his flight from Constan-

tinople to Cairo that M. Bonnier, the

French airman, passed over the Holy City

in his monoplane, descending upon the his-

toric plain of Rephaim, a short distance

south of Jerusalem. It was on this plain

that King David met and defeated the

Philistines. Never, in modern times, was

the city so excited.

It poured out en

masse to see the airman and his machine

-Christians, Jews, and Moslems.

photograph depicts the airman about to

leave for Cairo. The Holy City may be

Our

seen on the extreme left and the Mount of

Olives on the right.

Revolving Cylinder Motor on a

Motorcycle

HE revolving cylinder internal combus-

tion motor, which failed so dismally

on the single make of automobile on which

it was used, but which since has "proved"

itself in connection with the aeroplane, is

due to have a tryout in motorcycle ser-

A machine mounting a three-cylin-

der motor of that type has been developed

by a Connecticut inventor who now is com-

vice.

pleting arrangements to manufacture the

machine in great numbers.

The motorcycle, which is pictured here-

with, does not differ widely, exclusive of

the motor, from accepted practice. The

motor is mounted inside the rear wheel

----------- 20 -----------

disadvantages, time will tell.

Floating on the Dead Sea

HE wonderful buoyancy of the Dead

Sea, that strange inland sheet of water

in Palestine, is proverbial.

It is some

47 miles long by 9 miles wide, and lies no

less than 1,200 feet below the surface of

the Mediterranean, the lowest-lying lake

on the face of the globe. Its waters are

so bitter that fish cannot live in them.

We get an idea of its density when it is

stated that in a tom of water from the

Atlantic there is 31 pounds of salt against

187 pounds from a like quantity in the

Dead Sea. The result is that it is impos-

sible for a human being to sink in these

waters, and the accompanying photograph

depicts a tourist reading his guide book

while floating on the surface of the water.

Mexican Armored Motor Car

HE accompanying photograph shows

a standard American two-ton motor

truck chassis which has been converted

into a motor car by the Mexican Constitu-

tionalists.

It was not known to what use the

chassis was to be put when delivery was

made to a southern dealer, but the result

pictured is a striking reminder of the

adaptability of the motor chassis, and

shows the ingenuity displayed by the pro-

gressive Constitutionalists. Interior space

of the armored body is used for carrying

ammunition, rifles, etc., while the deadly

fire of machine guns can be directed

through small portholes in the walls. The

car is fitted with armored wheels for oper-

ation upon the railroad, where a continu-

ous stretch of track remains, or by quick

adjustment the wheels can be changed to

run over the roads directly into the Zona

Guerra.

Two of the World's Seven Wonders

SPIRITED voting contest has just

A been concluded in Germany to decide

which are the seven wonders of the twen-

After the enormous vol-

tieth century.

of votes cast were counted, it was

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A Smoke and Fume Monitor

By W. W. Strong

ANY furnaces are not placed so that

the fireman can see the top of the

smokestack. Neither does the manager of

the power plant often see the black fuel

issuing from the top of the stack.

other words, small account is given to this

item of waste and the source of a fume

and smoke nuisance in many cases.

Naturally a fireman is not careful about

the part of his work to which no one pays

any attention. The result is carelessness,

and it is to this carelessness and lack of

interest that much of the trouble of smoke

inspectors is due.

smoke monitor is to furnish an ever-pres-

The purpose of the

ent educational guide to the fireman, a

conscience ever ready to prick at his con-

tentment if he is not firing properly.

These d

The smoke monitor rings a bell and turns

on a red light at the furnace door when

the furnace is emitting smoke of a density forbidden by

the city ordinance. The smoke monitor works day and

night, and a recording mechanism can be attached to it.

Besides the smoke monitor there should be a set of

directions telling the fireman just what to do when

the bell is ringing.

The smoke monitor is a very compact piece of appa-

ratus, and is entirely electrical in its action.

from 60 to 100 watts of energy, and this is the only cost

of maintenance, since there are no moving parts to the

It uses

apparatus to get out of repair.

In the illustration the monitor is shown with all

the parts together, though it is probably more conveni-

ent to place the bell B, the red lights RL, and the relay

R by themselves, while the transformer T is placed near

the stack.

The transformer is a comparatively light

one, giving about 20,000 volts potential (when on the

110 circuit) across the spark gaps SG. In parallel with

this spark gap is a similar one placed in the smokestack.

When there is little, if any, smoke in the stack the.

resistance is low and the discharge takes place in the

stack.

When smoke of a given density (say one third

black) appears in the stack, the resistance is so in-

creased that the discharge takes place at SG, and this

discharge is a series of oscillatory sparks. The remain-

der of the apparatus consists of a coherer and relay

and operates in the same way as in wireless telegraphy,

turning on a bell and red lights whenever sparking

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Simple Patent

Lifeboat Arrangements on the "Britannic

T is certain that, up to within the last two or three

years, the development of the lifeboat and its means

for launching has lagged far behind the development of

the ocean liner itself. To-day, however, a great deal

of thought is being directed, not merely to the construc-

tion of the lifeboats themselves, but to the provision of

strong and effective means for getting them quickly

and safely overboard, even when they are loaded to

their full capacity. We present two drawings which

show the admirable way in which Harland & Wolff

have worked out the problem on their new liner, the

"Britannic," which will make her maiden trip to this

port during the present year. The lifeboats are nested,

two deep, in groups of five, and each group is served

by a pair of powerful electrically-operated davits. The

old boat davits have always seemed to us to be rather

primitive affairs, lacking in the necessary strength and

rigidity; but no such charge can be laid against the

The main members

installation on the "Britannic."

of the davits are of stiff lattice work construction,

hinged at the decks and capable of swinging through a

wide arc. Each pair can be swung over so far inboard

that it can pick up a lifeboat from the center of the ship

and swing it out so far outboard that the risk of its

being crushed against the ship's side is practically elim-

Access to the boats is gained by stairways

inated.

which lead to platforms running between the several

tiers of boats, from which the passengers can step con-

These stairways and platforms

veniently into place.

are not shown in our illustration; but they are sc

arranged that the loading of the boats can be ex-

peditiously done and without any confusion or crowd-

ing. The boat lowering gear is driven by electric mo-

tors of such power and so arranged that the lowering

can be done very speedily, the boats being maintained

on an even keel and released immediately

on reaching the water.

A Smoke and Fume Monitor

By W. W. Strong

ANY furnaces are not placed so that

the fireman can see the top of the

smokestack. Neither does the manager of

the power plant often see the black fuel

issuing from the top of the stack.

other words, smal account is given to this.

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bristle, owing

TUS

nature.

A Simple and Convenient Fish Rod

N ingenious combination of a spring balance and

fishing rod can be made without disturbing the gen-

All' that is needed is to

eral appearance of the rod.

hollow the end so as to make a regular tube, or else fit

on a short piece of tube.

tached a spring, and the lower end of the spring carries

Part way up the tube is at-

The weight of the

a short hook for hanging the fish.

fish thus draws down the end of the spring in the same

way as in the usual spring balance, and by cutting a

small window in one side of the tube, a scale can be

put on a piece of glass fitted in the window, correspond-

ing to a pointer attached to the spring. The whole is

simply a spring balance, built into the end of the fishing

rod, and it is all inclosed and not in the way at ordi-

nary times.