340 MONTHLY WEATHER REVIEW. OCTOBEII, 1908
telegraph office in the Transvaal for publication on a notice
board. Synoptic maps, however, are not published on account
of the expense. Altho a large land area lies to the west of
the Transvaal, the advantage of this circumstance for weather
forecasting is neutralized by the lack of telegraphic meteoro-
logical stations in the region in question. However, a daily
telegram is received from Swakopmund, German Southwest
Africa, giving the height of the barometer. Besides the fore-
casts for twenty-four hours, seven-day forecasts are occa-
sionallx issued.
An Angstrom pyrheliometer was added to the equipment
of the central observatory during the year. An investigation
of the daily amount of chemical radiation from the sun was
also undertaken.
Other interesting features of this report are charts showing
mean rainfall and mean cloudiness over the Transvaal, based
on the records of three years, and a full account of the code
used by the observers for weather telegrams.
GERMAN METEOROLOGICAL SOCIETY. HAM BURG, 1908.
The eleventh general meeting of the German Meteorological
Society was held at Hamburg September 28-30. The society
having reached the twenty-fifth year of its esistence, the
meeting was regarded as of special interest, and it was at-
tended by a large number of members drawn from all parts
of the Empire. In addition, Australia was represented by
Messrs. Hunt and Barton, the British Isles by Mr. Harries,
France by M. Teisserenc de Bort, Hungary by Hofrat Konkoly,
Norway by Vice-Director Aksel Steen, and the United States
by Professor Rotch. Professor Hellmann, as president of the
society, opened the meeting with a congratulatory speech
suitable to the interesting occasion. Admiral Herz, director
of the Deutsche Seewarte, was called upon to respond for the
official meteorological service; Mr. Harries, as the represen-
tative of the Royal Meteorological Society, for the foreign
visitors; Professor Dr. Voller for the physical institutions,
and Doctor Friedrichsen for the geographical societies. Doc-
tor Hellmann then gave an address on the (< Dawn of Meteor-
ology.” Subsequently there were five sittings, at which twenty-
five papers were discust, the subjects being general meteor-
ology, the meteorology of the upper atmosphere, weather fore-
casting, and atmospheric electricity. Such an amount of
work could only be got thru by steady application from
9 a m. to 6 p. m. daily. To make up for this the social side
of the occasion was not neglected. On Monday night, the
28th, visitors were the guests of the senate of the free town
of Hamburg, in the Rathhaus; on Tuesday there was a dinner
at the Hamburger Hof; on Wednesday the Hamburg-American
Steamship Company took the visitors round the harbor, and
on a trip some miles down the Elbe, concluding the excursion
with a visit to the liner Konig Wilhelnt I1 On Thursday the
Seewarte and other institutions were thrown open to the visi-
tors, and the afternoon and evening were devoted to the kite
and balloon station at Gross-Borstel. The final act of the
gathering was a dinner given by Professor and Mrs. Koppen.
It was further announced that MM. Angot and Teisserenc
de Bort, Professor Rotch and Doctor Shaw had been elected
honorary members of the society.--Symonds Meteorological Muya-
sine, October, 1908.
AS TO A DETAILED CLOUD CLASSIFICATION.
Meteorologists are not all of one opinion as to the wisdom
of distinguishing and naming eubvarieties of the simple types
of clouds recognized in the International Classification. Mr.
A. W. Clayden, one of the most successful photographers of
clouds, recently exhibited some of his pictures at the Franco-
British Exposition, and these were labeled in accordance with
the elaborate nomenclature proposed in his book ‘( Cloud
Studies,” published in 1905. They bore such names as cirrus
ventosus, cirrus communis, cirrus inconstans, alto-cumulus
castellatus, etc.
In the September number of Symons’s Meteorological Maga-
zine Mr. L. C. W. Bonacina criticises these names and expres-
ses the opinion that they do not represent sufficiently well-
defined types to be of utility. Beyond the simple names of
the International System, he thinks that a description, rather
than a name, is needed to indicate clearly the character of the
clouds in question. A contrary opinion, however, is exprest
by M. Albert Bracke, the editor of la Revue NQphologique, in
the October number of the latter journal. M. Bracke de-
clares that the subdivisions of the simple types, which have
been described by severe1 cloud specialists, are themselves
quite typical, end he himself uses the nomenclatures of Clay-
den and Vincent, both of which he says are easily learned and
enable one to express in a word or two the aspect of the sky
at the time of observation.
INSTALLATION OF AUTOMATIC RIVER STAGE
REGISTEFt AT HARTFORD, UONN.
By Wsr. W. NEIF’ERT, Lucal Fmecastrr. Dated: Hartford, Chum, October 10, 1908.
An event memorable in the annals of Hartford was the
((Bridge Celebration” of October 6-8, 1908, it being the dedi-
cation and the laying of the last stone of the beautiful and
durable granite bridge across the Connecticut, which is about
one-fifth 0.f a mile wide, at this place. At the very inception
of the designs for the bridge, Government officials saw the
advantage of being able to secure automatic records of river
stages which would be of special interest and value to the
people of Connecticut and incidentally to the inhabitants of
the 12,000 square miles of territory drained by the Connecticut
River. The gaging of such a noble stream gives important
data that are of great interest in meteorological work, as well
as of much practical value to water-power plants, farmers,
shippers, and the lumbering industry. Thru the courtesy of
the Bridge Commission provision was made for the proper
accomodation of a river stage register within one of the main-
channel piers of the bridge indicated by arrow in fig. 1. The
Chief of the Weather Bureau, appreciating the durability of
the structure, directed that a register be installed, and this
work was completed on September 8, 1908, under the super-
vision of Mr. D. T. Maring, Assistant Chief Instrument Di-
vision, of the Central Office. The register is of the latest im-
proved Friez pattern, operating continuously and automatically
and is the only one of the kind in present use in this service.
The gage well.-The bridge pier containing the apparatus
has a cylindrical shaft, or well, 4 feet in diameter, reaching
from a vault or room immediately under the sidewalk of the
bridge down to the bed of the river. Access to the interior of
the pier is gained from an iron trap-door in the sidewalk of
bridge and a step-ladder to the floor of the vault. The well open-
ing around the pipes is covered by a strong wooden platform
with detachable manhole. From the river the water is admitted
to this well by a &inch pipe extending horizontally from the
down-stream outer surface of the pier, and consequently the
water in the well rises and falls with any rise or fall of the
water outside. Within the well is the gage-float guide, con-
sisting of a 10-inch cast-iron pipe which extends vertically
from 34 feet above the surface of the well to 4 feet below the
zero of the gage, where it rests on two short lengths of rail-
road rail placed on the rock foundation. These rails provide
a solid base for the heavy pipe and also an intake for the
water, tho to produce a better circulation in and around the
lower end, a hole about 5 inches wide and 6 inches long was
cnt out of the float pipe at a point about 3 feet from the bot-
tom. This large pipe is made up of three 12-foot lengths of
cast-iron pipe and a top section of wrought-iron pipe 11 feet
long. These four sections are well secured together by packing
and cement in the bell-joints, and lined up so as to be perfectly
M o m Y W-EATHFAR REVIEW. 341
vertical. To this pipe is attached by special iron olamps 44 of the instrument is fastened in suoh manner that the sprocket-
feet of la-inch galvanized-iron pipe for the counterweight, wheel of the register comes directly over this pipe, aa illus-
also plumbed to be vertical and parallel with the float-pipe. trated in fig. 2.
The registering apparatus.-To the top of the gage-float guide- The instrument, with cover case open, is clearly shown in
pipe is screwed a cast-iron flange to which the wooden support fig. 2. It consists of a metal base on which is mounted the
I --
FIG. 1.- Connecticut River Bridge, Hartford, Corm.' (Looking north. Main-channel pier, No. 1, indicated by arrow-river-gage in vault at x.)
ti
Fm. 2. -Automatic river-eaee register, with glass cover raised.
48-3
usual eight-day power clock for propelling a recording-pen
carriage by means of a feed-screw. With the clock mechanism
is a revolvable record-drum 8 inches long and 12 inches in
circumference, which carries the weekly record-sheet. The
delicately mounted sprocket-wheel on the right has motion
communicated to it by a very light and flexible phosphor-
bronze perforated tape or band passing over accurately spaced
pins on the circumference of the wheel. The tape is at-
tached at one end to a 7-inch copper float and at the other to
a small counterweight running up and down in the smaller
pipe. As the water in the shaft rises it carries the float with it, causing the tape to move. This movement of the tape
turns the sprocket-wheel, which communicates its motion to
the record-drum thru suitable gears having a recording ratio
of 1 to 20. One revolution of the drum (or 12 inches) thus
equals 20 feet rise or fall of water. The engraved part of the
sheet is also 8 by 12 inches, ruled and spaced to indicate hours
of time, and feet and fifths of water stage. The perforations
of the tape provide for a range from 2 feet below the gage
zero to 39 feet above.
As installed the register is fitted with a glass case having
lock and key. Over all is placed a rubber sheet to keep out
dirt and dampness, and on the outside is attaohed a notice
warning the public not to interfere with the apparatus.
Remark8.-Experience with this installation suggests a word
of caution in future installations of this kind. Acting under
instructions, the contractors put in only a 4-inch intake pipe
between the bottom of the well and the channel outside of
'This is the largest stone arch bridge in the world. Total length 1,120 feet, nine spans. Maximum clear height to intrados of arch above Iow water, 46 feet. Width outside spandrel walls, 82 feet. CJear road-
way, 80 feet, vis: Two l0-foot sidewalks and 60 feet between curbs for two carriageways and two street-car trwb. Foundations carried to 60
feet below low water. Weight of largest finished stone used in the con- struction, about 40 tons. Total amount of masonry in bridge proper, about 100,OOO cubic yards. Cement used in construction, about 125,000 barrels. Cost of bridge $1,600,000, and with approaches complete nearly
$,?,OOO,OOO. Chief Engineer, Edwin H. Graves; Deputy Chief Engineer, John T. Henderson; Assistant Engineer, Edward W. Bush.
343 M O N m Y WEBTHER REVIEW. OCTOBER, 1908
the pier. This was laid in 1906, and it had become completely
filled with sand and silt at the time of installing the register
in 1908. This pipe should have been at least 8 inches in
diameter, and there should have been another pipe outlet to
the channel arranged so there would always be a slight move-
ment of water thru the bottom of the well. Thus the inlets
would tend to keep themselves clear. A 2-inch pipe is now
in place several feet above the 4-inch pipe, and will, of course,
do this to some extent when the water is above that point, but
it is feared it will hardly prove suficient for the purpose, and
a special annual cleaning out of the bottom of the well and
the lower inlet-pipe may be required.
The 10-inch float-guide pipe was installed in sections as the
work of building up the pier progressed, but no special efforts
were made to avoid the accidental deposit therein of wood,
crusht stone, cement, and filth by careless workmen. Both
well and pipe should be kept closed during the building opera-
tions of all bridge piers intended for the use of registering
river gages. Where possible, more light and ventilation should
also be provided for the vault room containing the registering
apparatus.
The records thus far obtained at Hartford have been checked
daily by eye observations of the ordinary river-gage, and have
been found exceedingly accurate. They will doubtless prove
of great value in the river work of this section.
"HE METEOROLOGY OF MARS.
By Prof. SIMON NEWWMB. [Heprinted from Harper's Weekly BJC 25th of July 190S.l
The study of the atmospheres of each of the other planets
of our solar system is likely to add something to our knowl-
edge of our own atmosphere, and we commend to our readers
the following extract from a longer article by our distin-
guished colleague in astronomy.-C. A.
There are two points concernlng Mars on which we can speak with a fair approach to certainty, and which will be most valuable in enabling us to interpret observations. I n the flrst place the atmosphere of Mars is so much rarer than that of
the earth that the most delicate observations by Campbell with the great spectroscope of the Lick Observatory have failed to show any evidence
whatever of ita existence. This does not prove that no atmosphere exists, because there are other sources of evidence; but in the opinion
of Campbell i t shows that the density of the atmosphere can not amount
to one quarter that of the earth. This view is strengthened by the com-
parative rarity of clouds upon the planet. Portions of the surface are seemingly obscured by vapors from time to time, but this is rather es- ceptional in any one region.
The other point on which we have some Hght, apart from the revela- tions of the.spectroscope, is that of the probable prevailing temperature. A reliable estimate of this important element in Martian meteorology
has been possible only in recent times, since the law of radlation of heat
has been determined. The reasoning on which the estimate is based is so simple that I shall venture to set it forth. We all know that a hot body is contiuually radiating heat, so that flre in the chimney place will warm the opposlte walls of the room even if the air is below the freezing point. We feel this radiation only in case
of very hot bodles, like the coals or flame of a flre. But accurate experi- ments show that every body, however cold i t may be, radiates heat when
left to itself without receiving heat from any outside For ex- ample, during the night the earth radiates heat into space hour by hour,
so that, as a general rule, i t s surface grows cooler during the entire
night. Exceptions occur only when a current of warm air sets in. We know that, during the polar winter, although the Arctic regions receiw
a little warm alr from the temperate zone. the temperature continually falls through radiation into the sky, month after month, until it reaahes
a degree far below any ordlnarily experienced in our latitudes. It fol- lows that any heat thus radiated by a planet, like the earth or Mars,
must be gained from some source, else the temperature will fall below any that we ever experience on the earth, even below that of liquid air.
There ie practically only one source from which the necessary heat is derived either for the earth or for a planet. That source is the sun. True, a little heat is received from the stars and a little Prom the interior
of the earth, but these amounts are so small as to be scarcely measurable. Now, suppose a perfectly cold planet like the earth or Mars exposed to the
sun's rays, and set rotating on ita axis while revolving around the sun
'The law followed is that the higher the temperature of a body the more rapidly it loses heat by radiation.
in a regular orbit. It wlll gradually absorb heat from the sun and 80
rise in temperature. As the temperature rises, heat wlll be radiated at a rate which continually increases with the temperature, as we see in the case of the flre. A point will flnally be reached at whlch the amount of heat radiated is equal to the total amount received from the sun. Then the temperature wlll become stationary. It follows that if we know
how warm a body must be in order to radiate a certain amount of heat, and if we know how much heat I t receives from the sun, we cam approxi-
mately determine i t s temperature. The sun's radiation upon the earth has been determined with as much
certainty as the case admits of by several modern physicists, high among whom stands our late Professor Langley, Secretary of the Smithsonian
Institution. The result of these observations may be exprest in t h e following way. Imagine a flat vessel 1 inch thick, of any cross dimen-
sions, fllled wlth water and covered over water-tight. We thus have something which may be shaped like a very thin box. The main points are that the thickness of the vessel is exactly 1 inch, that i t is fllled with
water, and that one surface is blackened so that it absorbs all the heat which falls upon it. Let this surface be exposed to the rays of the sun as shown in the figure.' It is found that the amount of heat falling upon
it will sufece t o raise the temperature of the water 10 C., that is, about 1.8O F., in a minute. This, then, is the measure of the heat which the
sun radiates to a planet as distant as ours. Knowing i t for the distance
of the earth, we can easily compute it for Mars, because the intensity
diminishes aa the square of the distance increases. When Mars is nearest the sun each square mile of i t s surface receives about half ee much heat
as the earth, and at the greatest distance about one-third as much. This has long been known, but only recently has the other part of the problem
been solved-that of determinlng how warm the earth or Mars must be
in order t o radiate all the heat it receives. The temperature that is
necessary to produce this effect was long greatly underestimated. A curious instance is afforded by Langley's estlmate of the temperature of
the moon. He supposed that a body radiating as llttle heat as the moon does must be far below the freezing polnt. But when the law of radla- tion was flnally established, it was found that Langley's observatlons showed the temperature oP the moon to be not strikingly different from
that which prevails on the earth, tho i t might be much hlgher under a
noonday sun and much lower when turned away from the sun. Very interesting Is the agreement of the computed result with the temperature of the earth. It was formerly thought that the atmosphere seryed ee a
sort of blanket t o the earth, which allowed the sun's heat to pees thru
it and reach us, but permitted only of a very small amount being radi-
ated back. Probably there is some such blanketlng effect, but it is much
less than was supposed. In fact, when we calculate about what tem- perature the earth ought to have in the general average, t o radiate all the heat it receives from the sun we flnd i t to be not very dlfferont from
the actual temperature. The same remark applles to the moon. We thus have what every physical philosopher desires when he draws con-
clusions from a theory-practical te8t of the latter. The law of radiatlon, tho seemingly well proved by observation, might have been subject t o
more or less doubt as a method of determining the temperature of a
planet had i t not been conflrmed by the mse of the earth. Being con- firmed, we apply i t wlth confldence to estimate the temperature of Mars.
A simple calculation leads to the conclusion that the temperature of the surface of that planet must be everphere below the freezing point of
water, unless in its torrid zone, under a high sun. Another conclusion from the rarity of the air ie that the vicissitudes
of temperatnre are there far greater than upon the earth. We have re- marked that during our night the earth cools off by radiating into space
the heat which it received from the sun the day previous. Wealso know that the clearer and dryer the air the greater is the fall of tem-
perature, while the presence of clouds lessens the f a l l by interfering with radiation. The radiation and absorption of heat by the atmosphere are much less than by the earth, so that during the night the air gives back
to the earth an important part of the heat which i t has received from i t during the day. But on Mars the air is so rare that during the night it offers little impediment to the radiation. and does not contain much heat
to return to the surface of the planet. Moreover, in our Arctic regions, during the long polar night, the fall of temperature is lessened thru the intercommunication of the air by winds between the Frigld Zone and the warmer regions where the sun is shining. Now on Mars this feature also is wanting, and there is no such powerful agent t o limlt the f a l l of temperature in reglons where the sun is not shining. We, therefore, conclude that during the nlght of Mars, even in the
equatorial regions, the surface of the planet probably falls to a lower temperature than any we ever experienced on our globe. If any water exists it must not only be frozen, but the temperature of the ice must be far below the freezing point. When, as the Martian morning appears,
the sun's rays shine upon this cold region they can not begin to melt the ice until the temperature of the latter rises above the freezing point.
This will take a much longeritime than it will on the earth, bemuse the
heat received is, on the average, less than half as great as what we re- ceive. Without going into detailed calculations, we may say that it is scarcely possible that more than one or two inchesof ioe could be melted
Not reproduwd here.