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THE AIR ABOVE US

By

C. F. TOLLER

ARDLY was the soundingballoon invented than its availability as a means of exploring the atmosphere was recognized; and in a desultory way it has been utilized for this purpose ever since. Until recently it was a case of Mahomet and the mountain. Since the upper air would not come to the meteorologist, the latter was constrained to travel to the upper air, an undertaking demanding a greater expenditure of time, energy and courage than could be reasonably expected of the average man of science.

Today the meteorologist performs these journeys vicariously. The personal scientific balloon ascent has become the exception. The process now forming part of the daily routine of a number of meteorological observatories all over the world is to attach a delicate self-recording instrument to the balloon and set it free. The balloon is so constructed as to burst at a great altitude. A parachute carries

pens-how high the balloon ascended, how warm and how moist the air was at various levels.

The "sounding-balloon"-as this type of apparatus is called-soars to heights unattainable by the human aeronaut. One of these balloons sent up by the United States Weather Bureau a few months ago reached an altitude of 18.9 miles nearly 31⁄2 times the height of Mt. Everest.

The most remarkable thing about the atmosphere at the great heights reached by the sounding-balloon is its temperature. The upper air is intense

ly cold; but not so cold as we used to think. In the year 1902 a number of sounding-balloons had been sent up in the neighborhood of Paris by a French meteorologist, M. Teisserenc de Bort. An examination of their records disclosed the curious fact that in every case, after an altitude of about 61⁄2 miles was attained, the air stopped growing colder. Above that height the balloon passed through a stratum.

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INFLATING A SOUNDING-BALLOON AT PAVIA. THE HEADQUARTERS OF UPPER AIR RESEARCH IN ITALY.

the apparatus gently to earth. This may happen hundreds of miles (horizontally) from the place of ascent; but a conspicuous label, attached to the balloonbasket, informs the finder that a reward will be paid for the return of the precious instrument. As a rule it comes safely home in the course of events. Then the meteorologist pursues at his leisure the fascinating story traced by the recording

of nearly uniform temperature.

Meteorologists were quite unprepared for this discovery, and its announcement was received with considerable skepticism. Very soon, however, similar observations were reported from other parts of the world. Now we know that the phenomenon is not local or exceptional, but prevails everywhere. It appears that there is a layer of the atmos

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BALLOON AND KITE HOUSE AT THE MOUNT WEATHER

OBSERVATORY.

phere, just above

the level of the

higher clouds, in

which there is little

or no change of

temperature in the

vertical. This re-

gion was at first

named the "isother-

mal layer," but is

now more com-

monly called the

"stratosphere."

The height of its

lower surface

varies with a num-

ber of conditions,

the most important

of which is latitude.

It is at least over
the polar regions
and greatest over the equator. This fact
leads to a curious paradox. As our bal-
loon goes up, the thermometer records a
more or less steady fall in temperature;
and the higher the stratosphere, the
longer this fall continues. Hence the
lowest temperatures are reached where
the stratosphere is highest; i. e., within
the tropics. In the year 1908 a sounding-
balloon recorded 119 degrees below zero
Fahrenheit about twelve miles above Vic-
toria Nyanza, in the heart of Africa!
This is the lowest temperature ever ob-
served in the atmosphere.

[graphic]

Cellular kites are used. The "string" is of steel piano
wire, and is handled with a steam winch. This observa-

tory holds the world's record for the highest kite flight

23,826 feet. on May 5, 1910.

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Two other aerial vehicles serve the
meteorologist. The captive balloon re-
places the kite in certain conditions of
wind and weather. The "pilot balloon'
is a cheap and simple device for gauging
the upper winds. It carries no instru-
ments; the meteorologist simply sets it
free and observes its drift-usually with

If the finder will kindly pack in a box this Balleon, Cover, and Basket (the
Basket contains a meteorological instrumen and record), WITHOUT OPEN-
ING OR DISTURBING CONTENTS in any manner, and return by Express,
Collect, to

Mount Weather Observatory,

Bluemont, Va.

TWO DOLLARS will be paid for the service Please fill out and mail the card
inside this envelope, also use the inclosed tag on the express package.

THE KIND OF ENVELOPE THAT IS ATTACHED TO THE SOUNDING-BALLOONS
SENT UP BY THE WEATHER BUREAU.

A remarkable feature of these balloon ascents is that the majority of the

instruments and records are ultimately recovered and returned to the place

of ascension-sometimes hundreds of miles distant.

THE KITE STATION ON THE SHORES OF LAKE CONSTANCE.

and the remainder of the atmosphere, extending hundreds of miles above it, we should find the former about three times as heavy as the latter. This follows from the fact that the air is highly compressible; relatively dense below and exceedingly tenuous above. At great heights its density is equivalent to what, in physical experiments, we should regard as a very excellent "vacuum."

The troposphere differs from the differs from the stratosphere in several respects besides temperature. All clouds consisting of water and ice occur within it. It contains practically all the moisture of the atmosphere. Lastly, it is the seat of all the great whirling commotions of the air that we know as "storms."

What lies above the stratosphere? Are there yet other layers of the atmosphere as distinct from the stratosphere and from each other as is the stratosphere from the troposphere? These questions carry us beyond the range of ascertained facts and into a realm of interesting. speculation.

Near the earth's surface, "air" is always and everywhere very nearly uniform in its composition. Above the active circulation of the troposphere, however, there is little doubt that the atmospheric gases tend to distribute themselves according to their atomic weights; the heavier below, the lighter on top. The upward extent of each constituent of the atmosphere can be computed; and from such a computation it appears that oxygen dwindles to the vanishing point at an altitude of about fifty miles, at which level the "air" is

[graphic]
[graphic]

A FLOATING UPPER-AIR OBSERVATORY.

Germany's very unusual "kite station" at Friedrichshafen. on Lake Constance. Kites and balloons are sent up daily from a moving steamboat.

The stratosphere has its drifts and currents, but apparently no violent disturbances. Although it has no clouds, in the ordinary sense of the term, it has occasionally been invaded by masses of dust hurled aloft by volcanic eruptions. This happened during the great outburst of Krakatoa, in 1883. For several years thereafter the dust-clouds were seen shining with reflected sunlight through the short summer nights, and they were widely known as "the noctilucent clouds." Their altitude was estimated at about 50 miles. Similar clouds were seen after

mainly nitrogen; that nitrogen vanishes rather abruptly a little higher, leaving hydrogen in possession of the field. Just what changes in optical, acoustical and other properties of the atmosphere may be implied in this change of composition is much too recondite a question to discuss here. It appears to have been settled to the satisfaction of certain German meteorologists, who talk of two atmos

LARGEST SMYRNA FIG TREE THE photograph on page 106 shows two exceptionally unique features. The tree is the largest and oldest Smyrna fig on the American continent while the thirty-eight persons standing in the foreground are all members of a single family.

I. N. Parlier, a California pioneer, settled on government land in the fertile San Joaquin Valley, thirty-two years ago. About twenty-eight years ago when the Department of Agriculture was searching for a place congenial to the growth of the Asiatic Smyrna fig, Mr. Parlier planted the tree. The genuine Smyrna fig has only been successfully raised on this continent in the San Joaquin Valley, and this specimen demonstrates that although the tree does not seem to flourish elsewhere, it certainly grows here, with a vengeance.

The tree is nearly eight feet in circumference at its base. Its branches have a spread of sixty-eight feet. Its tallest twig is thirty-seven feet above the ground. Through the stronger branches in the center of the tree bolts have been set from which wires have been strung to support other weaker branches, as the wood of the fig is very brittle. A wooden trellis, ten feet high, supports all the

FIRST COLLISION IN THE AIR. AT THE TRIAL GROUNDS OF THE FRENCH MILITARY AVIATION CORPS AT LA BRAYOLLE. Two MILITARY AERO PLANES COLLIDED IN MIDAIR. THE MACHINES WERE TOTALLY WRECKED AND THE TWO PILOTS. CAPTAIN DUBOIS AND LIEUTENANT PEIGNAN, KILLED INSTANTLY,

lower limbs and when the tree is in foliage a lovely shaded court is formed below.

So much does Mr. Parlier think of his "giant" that when he noticed the tree was becoming cramped for growing room, its branches at one end being obstructed by his house, he simply tore down the back portion of his residence and recon

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THE WRECK OF THE AEROPLANES.

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ALL ONE FAMILY GATHERED UNDER THE LARGEST SMYRNA FIG TREE IN AMERICA. The grandfather is the seventh person-not considering the baby-counting from the right.

structed it as shown in the picture. Now, the tree expands unrestricted by any artificial restraints that man may have placed around it.

It bears a large crop of fruit annually, when properly pollinated, and the figs have a very delicious, nutty flavor.

Mr. Parlier is sixty-two years of age, but no casual observer would give this youthful enthusiast credit for having passed farther than the two-score mile post much less believing that he is father or grandfather of all the people standing about him grouped in the picture shown above.

ENGINE WITH HEADLESS
CYLINDERS

BELIEVING that more power can be

secured from an engine exerting the force of steam in two directions at once instead of one as in the ordinary engine, an inventor of Biloxi, Miss., has built an engine with headless cylinders.

The engine has two cyinders one above the other as shown in the illustration, each containing two pistons. The steam enters at the middle instead of at the ends of the cylinders as in most engines and drives the two pistons apart, forcing

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