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The opportunity she has now had the good fortune to secure augurs well for her future career.

Though the American Scandinavian Foundation grants about 40 fellowships annually, this is the first time one has been awarded in the fields of meteorology and oceanography.-A. H. Palmer.

DEFECTIVE THERMOMETERS.

The following editorial appeared in "The Medical Critic and Guide" for July, 1920:

"We have referred several times before to the fact that many thermometers. sold in this country are worthless, not only worthless, but extremely dangerous. It is better to have no thermometer at all and judge of the patient's condition by the general symptoms than to have a thermometer that registers falsely. Nobody should buy a thermometer without a guarantee of its correctness. And manufacturers selling falsely-registering thermometers should be liable for dam

ages.

"To demonstrate to physicians and nurses the worthlessness of some of the thermometers upon which they have been depending, the New York Department of Health established a testing outfit and 156 clinical thermometers obtained from doctors and nurses were tested. Of these 156 thermometers 84, or 54 per cent, were found defective. A thermometer registering considerably above or below the real temperature is a real danger to the patient, worse than no thermometer at all.

"The New York Board of Health is trying to establish regulations for the sale of clinical thermometers and we trust that the manufacturers will live up to these regulations."

One would infer from the price of a clinical thermometer that it is carefully made and tested. Usually such instruments are sold only by high grade drug stores or by dealers in scientific instruments. If 54 per cent of such instruments are defective, what must be the proportion of defective thermometers intended to record air temperatures, and which may be purchased from any corner drug store, or even from one of Woolworth's 5 and 10-cent stores? Little wonder that during periods of extreme heat or extreme cold the privately owned thermometers show temperatures very different from those officially recorded.— A. H. Palmer.

FURTHER DISCUSSION OF THE KILOGRAD SCALE.1

BY ALEXANDER MCADIE.

Professor Marvin evidently has in mind an absolute scale. We cannot at present make a usable absolute scale. The so-called absolute in common use, is an approximate absolute. On this point we all agree. The kilograd scale is not an absolute scale per se but one that will meet the needs of physicists better than the present so-called absolute. It has many of the advantages of the absolute scale, and except where great precision is needed, will be acceptable since the zero is so close to the absolute zero. There are only two fiducial points; the melting point of pure water at a pressure of 1000 kilobars and the absolute thermodynamic zero. The boiling point follows on the basis of 100 scale divisions. It is doubtful if there will be much confusion in thermometry by recognizing the new pressure datum. Thermometry is now in such a condition that a new lead may point the way to order and improvement. Certainly many chemists 1 See July-August BULLETIN, pp. 84-86.

and physicists are reducing observations today to a 750 mm. of mercury basis; and this is close to the 1000 kilobar level.

Mr. Woolard's remark favoring 1366 and 1000 may be likened to advocating the erection of a church spire but omitting the church. It is to be regretted that he has not apparently tried out the scale with a view to serviceability. Comment and criticism along this line will be helpful; for the main purpose is to know whether such a scale will be of service to Meteorology.

BALL LIGHTNING.

An account of ball lightning seen at the U. S. Weather Bureau office, University of Missouri, Columbia, on April 20, 1915, at 2.20 P.M., has recently been brought out of the weather record of that station. Mr. George Reeder writes as follows:

I was sitting at my desk facing the open door and the telephone on the small table. Thunder had occasionally been heard in the south since 1.50 P.M., and light rain began at the station at 2.10 P.M.

Mr. Robert E. Seaton, my first assistant at the time, left his desk, going to the window to look at the sky. The window looks out south. The sky immediately over the station was hidden by a dark-gray cloud, nearly rectangular in shape, from which light rain was falling. Mr. Seaton had barely taken his position at the window (2.20 P. M.) when there was a sharp report, closely comparable with the report of a sporting rifle. There was an immediate answering click at the telephone. I instantly looked up, and saw a palish red, slightly corrugated ball, apparently 11/2 to 2 inches in diameter, or about the size of the outer rim of the mouthpiece of the telephone, moving across the space, about 6 feet, between the telephone and the window by which Mr. Seaton was standing.

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The fire ball seemed to float as a liquid bubble does, though it seemed solid. It kept a fairly straight line for the window; it rolled over the windowsill, and disappeared, not into the outer air, but flickered out like a bubble. There was no explosion or sound of any kind following the click of the phone; there was no odor nor did it leave any marks on the windowsill. Mr. Seaton ceived no shock or injury of any kind. The telephone was not in the least damaged nor did it bear any marks to show that the ball actually came out of the mouthpiece. I cannot say positively that the ball came from the mouthpiece but it was but an inch or so from that object when I first saw it. The click of the phone and my looking up was but a fraction of a second apart. I should say that the ball took about two or three seconds to cross the space between the telephone and window. There was no more thunder after that one sharp report.

Inquiry as to whether Mr. Seaton has also seen the ball elicited the following additional information. Mr. Reeder in a letter dated August 12, 1920, says:

I will quote here a part of the short conversation that took place immediately following the occurrence of the phenomenon:

MR. REEDER: "What is the matter, Mr. Seaton?"

MR. SEATON: "I must have been dreaming, but I could swear I saw a ball of fire roll over (or on) this window sill."

Further exchange of views followed. We agreed as to the size, color, and that it seemed somewhat wrinkled. Neither of us saw flash or spark.

With regard to ball lightning in general, the following quotation may be of interest:

Curious luminous balls or masses, of which C. de Jans102 probably has given the fullest account, have time and again been reported among the phenomena observed during a thunderstorm. Most of them appear to have lasted only a second or two and to have been seen at close range, some even passing through 102 Ciel et terre, Bruxelles, 1910, 81, 499.

a house, but they have also seemed to fall, as would a stone, 103 like a meteor, from the storm cloud, and along the approximate path of both previous and subsequent lightning flashes. Others appeared to start from a cloud and then quickly return, and so on through an endless variety of places and conditions.

Doubtless many reported cases of ball lightning, probably the great majority, are entirely spurious, being either fixed or wandering brush discharges or else nothing other than optical illusions, due, presumably, to persistence of vision. But here, too, as in the case of rocket lightning, the amount and excellence of observational evidence forbid the assumption that all such phenomena are merely subjective. Possibly in some instances, especially those in which it is seen to fall from the clouds, ball lightning may be only extreme cases of rocket lightning, cases in which the discharge for a time just sustains itself. A closely similar idea has been developed in detail by Toepler. 104 It might either disappear wholly and noiselessly, as often reported, or it could, perhaps, suddenly gain in strength and instantly disappear as sometimes observed, with a sharp, abrupt clap of thunder.

To say that all genuine cases of ball lightning, those that are neither brush discharges nor mere optical illusions, are stalled thunderbolts, certainly may sound very strange. But that, indeed, is just what they are, according to the above speculation, a speculation that recognizes no difference in kind between streak, rocket, and ball lightning; only differences in the amounts of ionization, quantities of available electricity and steepness of potential gradients.-W. J. Humphreys.*

103 Violle, Comptes rendus, Paris, 1901, 182, 1537.

104 Annalen d. Physik, 1900, 22, 623.

*Jour. Franklin Inst., Aug., 1918, p. 218 (part of "Physics of the Air").

MISCELLANEOUS METEOROLOGICAL NOTES.
[Submitted by A. H. Palmer.]

As a result of damage done by hail during a severe thunder storm on July 2, 1920, the Eastern Iowa Mutual Hail Association has paid $3,317 insurance to individuals residing in the vicinity of Postville, Iowa.

The city of Oakland, California, maintains a meteorological and astronomical observatory known as Chabot Observatory, and located in the suburbs of that city. It is maintained under the direction of the Board of Education as a part of the school system, and is open to the public during certain hours of the day and evening. At the present time complete meteorological apparatus similar to that of a first class station is being installed. On the east side of San Francisco Bay there are four cities, Oakland, Berkeley, Alameda and Richmond, with a combined population of approximately 350,000 people. In litigation involving weather data, records from Chabot Observatory and those kept by the University of California, in Berkley, are frequently consulted.

As there are approximately 150 aeroplanes in commercial use in California at present, and the number is increasing from month to month, the demand for aerological data continues to grow in proportion.

The South San Joaquin District maintains a large dam known as Woodward Reservoir, and located about 8 miles north of Oakdale, California. In order to determine the loss of stored water through evaporation, the Weather Bureau and the Irrigation District are coöperating in the measurement of evaporation. For the past two years a standard evaporation station has been maintained on the bank of the reservoir, and at the present time a supplementary evaporation pan is being installed on a float in the dam. A similar floating pan is maintained on Lake Tahoe, in the Sierra Nevada Mountains.

During the past few months there have been large railroad shipments of Casinghead Gasolene from Texas to California. Because of its high specific gravity, this gasolene expands greatly with increase of temperature. In making arrangements for these shipments, the Bureau of Explosives, maintained by the railroad companies, found it necessary to fill the tank cars only to a certain capacity, owing to the high temperatures encountered by those cars in passing through the hot deserts, under the cloudless skies of the Southwest.

At Greenland Ranch, in Death Valley, California, the air temperature, as recorded by a tested maximum thermometer exposed in a standard instrument shelter, rose to 100° or higher on 23 days during June, and on every day during July, 1920. The extreme maximum was 125°, recorded on the last day of July.—

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On July 10, 1913, the temperature there reached 134° F., the highest officially recorded air temperature in the world.A. H. Palmer.

MONTHLY WEATHER REVIEW, JUNE, 1920 (ISSUED Aug. 30, 1920).

The June issue of The Monthly Weather Review contains 20 contributions and I notes and abstracts, in addition to the usual material-bibliography, special (solar) observations, and weather, river and earthquake phenomena of the month. A third of the contributions are of appreciable length. The contributions are as follows:

*Relation between the annual precipitation and the number of head of stock grazed per square mile. J. WARREN SMITH. Pp. 311-317.

(See this BULLETIN, May, 1920, p. 55.)

*New aerological apparatus. S. P. FERGUSSON. Pp. 317-322, 20 figs.

(See this BULLETIN, May, 1920, p. 52.)

*A general theory of halos. C. S. HASTINGS. Pp. 322-330, 8 figs.

[The general theory of halos developed in this paper rests on the assumption that two kinds of simple ice-crystals elongated hexagonal rods and hexagonal plates are occasionally present in a tolerably transparent atmosphere; moreover, that these crystals subsiding in quiescent air would necessarily fall into four groups.

The first portion of the paper establishes the validity of the assumption by reference to well-recorded observations.

The second portion is devoted to a development of the consequences from the presence of each of these groups for various altitudes of the sun. It is there shown that all the authenticated features of complex halos are naturally explained (excepting certain rare multiple concentric circles) as inevitable consequences of the hypothesis. In addition, this portion gives a new means of classifying the various phenomena, showing unsuspected relationships as well as essential diversity in certain other cases where common origin was formerly assured.-Author's synopsis.]

A beautiful halo display observed at Ellendale, N. Dak. F. J. BAVENDICK. Pp. 330-331, fig.

The Boulder halo of January 10, 1918. E. W. WOOLARD. Pp. 331-332, 3 figs.

The Grand Junction halo of March 3, 1906. E. W. WOOLARD. P. 332, fig. Outline showing the formation of the elements of a halo complex. E. W. WOOLARD. P. 332.

*[These four short papers are included in the separate of Professor Hasting's article, as they are largely descriptive of actual occurrences of halo complexes covered by his theoretical discussion.]

1 See Mo. Weather Rev., June, 1915, Vol. 43, pp. 278–280.

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Simultaneous occurrence of halos and coronas.
E. W. WOOLARD, and C. F. BROOKS. P. 333.

Iridescent clouds. C. F. BROOKS. P. 333-334.

Discussion by C. NEGRO,

[The alternating reddish and greenish bands sometimes observed parallel to the border of a smooth lenticular cloud are ascribed to the increasing size of the cloud droplets inward from the edge, which places the successive zones in the cloud within diffraction rings differing in color.]

Some observations on a free-balloon flight made from Aberdeen Proving Ground, Md., June 3, 1920. DON MCNEAL. Pp. 334-335.

[The balloon got into a thunderstorm cloud and ascended rapidly apparently being lifted by the rising air as well as by release of ballast. At a height of about 5,200 feet the balloon emerged into the sunlight. Moderate-sized hailstones were seen passing down by the balloon. The heating of the gas in the balloon lifted it to 8,200 feet before it again entered the cloud. Now it descended precipitately in spite of the expenditure of more ballast. Heavy rain and cool air were cooling the gas, and descending winds seemed to hasten the downward motion. After several contacts with tree tops a safe landing was effected in a grassy field.-C. F. B.]

Daytime wind turbulence in a mountain valley. B. M. VARNEY. Pp. 336337, fig.

[An unusual example of wind turbulence in the daytime air stream in mountain valleys is found near Yosemite Valley, Calif. The stream as it flows east up the valley in the afternoon divides through two branch canyons, the current in the southeasterly branch turning sharply round a steep mountain spur. This spur and the configuration of the canyon walls sets up a rotation of air in the lee of the cliffs about an inclined axis, the lower end of which is at the spur, the upper end about a mile away to the east, the general trend being parallel to the side of the canyon. The path of an air particle near the periphery of this roll was found, by observations on the drift of tissue papers, to be that of a great spiral, the diameter of which seems to vary from nothing at the spur to perhaps 2,000 feet at the east end. Observed variations in the form of the spiral are due to changes in the local winds under the influence of topography.— Author's synopsis.]

A fog phenomena of San Francisco Bay. B. M. VARNEY. Pp. 337-338, fig. [Occasionally when ocean fog is covering the land and the Golden Gate west of San Francisco Bay, a local "fog bank" forms along the eastern shore of the bay while the rest of the region remains clear. Conditions of air and water temperature and of typography being seemingly unfavorable to the formation of fog in this zone, it is suggested that the fog may be due to forced rising of the humid westerly winds over convection currents, themselves cloudless, on the plain east of the bay, condensation resulting from this forced rise. This local fog bank disappears in the latter part of the day, due to the breakdown of the convection currents.-Author's synopsis.]

*Measurements of solar radiation at Madison, Wis., with Callendar pyrheliometer. E. R. MILLER. Pp. 338-343, 5 figs.

[Results of observations extending over nine years are summarized, and data of related phenomena of duration of bright sunshine and of cloudiness are given. A midsummer depression in the annual march of midday normal intensity is ascribed to a maximum of haze at that time, due in turn to the increased evaporation of water and stronger convection. Spring and autumn depressions in the annual march of sun and sky radiation upon a horizontal surface are explained as arising from the double maximum in the annual march of frequency of "Colorado lows." The suggestion is offered that this double maximum is produced by the most efficient coöperation at intermediate seasons of the stationary barometric depression in Northern Mexico and the eastward drift of the atmosphere, the annual oscillations of which are in opposite phases.— Author's synopsis.]

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