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itself was substituted for rainfall in obtaining comparable data for mountain locations. It was found that the conditions as shown by the soil-moisture evaporation ratio were 16 times as severe at the base as at the summit of a desert mountain.

In coast mountains, the conditions are reversed. At the summits the evaporation rates are higher than at the bases, and somewhat higher even than in the dry valley (Salinas Valley) on the inland side. The amount of soil moisture decreases from base to top. On the whole, then, the conditions for plant growth are best on the summits of desert mountains and at the bases of coastal mountains. Little data on this subject seem to have been collected.-C. F. B.] Distribution of sunlight and moonlight over the earth. Zomá Baber. Experimental animal climatology. V. E. Shelford. (Dec. 31).

SYMPOSIUM ON PRESSURE REDUCTION PROPOSED.

During the Chicago meeting, informal discussion brought out the desirability of having the outstanding feature of the Toronto meeting of the Society next December a symposium on improvements in synoptic charts, especially on the reduction of atmospheric pressure observations. This is a peculiarly international subject so far as Canada and the United States are concerned, for the weather maps of both countries contain observations made on both sides of the international boundary. Representatives of the Mexican meteorological service will be invited to participate, in view of the possibility of arranging an international exchange of observations with Mexico for purposes of our daily synoptic charts. The subject is such an important one, and presents so many difficulties that the present time is none too early to begin making the necessary studies.

The plan of such a symposium would probably involve the presentation of 4 to 6 carefully prepared papers, with an interval for discussion after each, and, at the end, possibly the adoption of a resolution for transmittal to the Chiefs of the national weather services involved and to the chairman of the International Meteorological Committee. Those interested are invited to communicate with the Secretary on this subject.

PRESSURE REDUCTIONS IN THE UNITED STATES.

In view of the proposed symposium on pressure reduction to be held at the Toronto meeting of the American Meteorological Society in December, it may be of interest to members of the Society, who have not had their attention directed to the importance of this question, to review a few of the points involved. In the first place, we know that as one ascends into the atmosphere, the barometric pressure, or weight of air above the observer, decreases; and, since this is true, in order that barometers may be comparable, they would all have to be located at the same elevation above sea-level. Obviously, this is not possible, and the only remaining solution of the difficulty is to decide upon some fixed level, and, by means of reduction formulae which have been accurately determined, reduce the pressure to this level. The level that is universally used is that of the sea, and the daily weather maps in all parts of the world show the isobars reduced to sea-level.

But the use of sea-level as a reduction plane is not altogether satisfactory, for several reasons. In the first place, as far as meteorological conditions go, sea-level does not represent anything except over the oceans. Most of the

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eastern half of the United States lies about 300 meters (roughly a thousand feet) above sea-level, and the western half of the country projects into the atmosphere to an altitude of many thousands of feet. Hence, if there were no other objection to the use of sea-level, it could at least be partially disqualified by the fact that it lies, from a few feet to over a mile and a half, below every official barometer of the Weather Bureau.

But there are other difficulties of a more practical nature. For instance, one of the terms in the hypsometric formula, or barometric reduction formula, is the mean temperature of the air column between the observer and the reduction level. In the case of reduction to sea-level there is, for the most part, a column of soil and rock instead of the column required by the formula. Nevertheless, the temperature argument employed in the reduction tables is the mean of the current surface temperature and the temperature 12 hours earlier. There is no physical reason why this temperature value should be used, for it does not represent the mean temperature of an air column at all. It is merely an arbitrary method of getting a temperature value, which, fortunately, where the imaginary air column is not too long, happens to suffice. But, in the Plateau region, where the reduction distance is great, the temperature argument may lead to a quite erroneous sea-level distribution of pressure. If the temperatures are lowered abnormally in the immediate vicinity of the ground by a snow-cover, or if the mean temperature during a twelve-hour period is raised abnormally by the occurrence of a chinook the "sea-level" pressure may be raised or lowered by several tenths of an inch in extreme cases, where, in reality, there has been no actual change in the reading of the station barometer. Thus, one or two stations which are experiencing a chinook may produce on the morning weather map a Low with considerable horizontal gradients extending toward its center from all directions. It is true that under such conditions, the wind direction will not conform to the pressure distribution, but this is an unsafe criterion because of the marked influence of local topography upon wind direction in mountainous regions. Similarly, the intense cold near the surface at two or three stations may considerably raise the reduced pressure and give an erroneous impression of the strength of a HIGH.

The Plateau region of the United States lies in a position of great strategical importance from the viewpoint of the forecaster, for it is not until cyclones and anticyclones have moved into the region of the West and Northwest, where stations are maintained, that much of a definite nature can be surmised as to their probable movement. Thus, the Plateau region, above all others, should have the best method of reduction, but, at present, it is the least reliable.

What is to be the remedy? How are we to banish the barometric bogies which haunt our weather maps? It is not a new problem: the weakness of the present method was recognized by Bigelow when he was instituting it over twenty years ago. But these twenty years have offered no substitute that will be certain to solve the difficulty. A symposium on pressure reduction at the Toronto meeting would, therefore, be a matter of great and timely importance.C. LeRoy Meisinger.

U.S. WEATHER BUREAU TO OPERATE UNDER LIMITED
APPROPRIATIONS.

The Act making appropriations for the Department of Agriculture for the Fiscal Year ending June 30, 1922, which includes provisions for the Weather Bureau, has finally passed the Congress.

It provides an appropriation next year for the Weather Bureau of $1,886,570, which is an increase of $10,000 over the appropriation for the current fiscal year. $9,000 of this increase provides "for investigations, observations, and reports, forecasts, warnings, and advices for the protection of horticultural interests from frost damage," and the additional amount is for an increase of official traveling expenses, in part.

This increase of $9,000 is a favorable action on the request contained in the estimates of the Weather Bureau to this Congress, for the extension of the fruitfrost service. As the value of the fruit crop has increased, its protection from frost by heating has become more extensively practiced, and the demands on the Weather Bureau for frost forecasts and specialized advice exceed its ability to meet them under present appropriations.

The Weather Bureau strongly urged in its estimates before Congress an increased appropriation of $200,000 for its aerological work, and it was a source of considerable regret that this item was not finally approved, although an increase of one-half this amount was passed by the Senate but later failed of agreement by the conferees on the part of the House and Senate. The main object of this project is to take observations in the upper air, which will be used in connection with observations taken at surface stations, for the purpose of adding to existing knowledge of the physics and dynamics of the air, and especially to furnish aviators with accurate information as to the weather conditions in the upper air and with forecasts which will aid them in flights or else to avoid flights under hazardous conditions. Forecasts are now being made for various flying zones, but the number of stations at which upper-air observations are being made are quite inadequate to represent sufficiently the territory to be covered. The Weather Bureau is the only Federal agency which collects and disseminates information of this character, which is indispensable to Army, Navy, post-office, and civilian flyers. Aerial navigation now creates a great demand which can be met only by increased appropriations and extension of the present service.

It is noted that the Congress, in its urgent necessity for economy, has not made any material increases in appropriations for the Weather Bureau, which will thereby be under the necessity of suspending maps and other details of work at a considerable number of its stations. It is simply a question of man-power on the one hand and the purchasing power of the stationary appropriations of the Bureau on the other. The remedy is-sufficient appropriations to pay adequate salaries to attract men possessing the qualifications that are necessary for the most efficient conduct of the work. Furthermore, paper, supplies, etc., required in the issue of weather maps in the conduct of Weather Bureau work must be paid for at much higher prices than formerly; also, rents, which are required to be paid at nearly 100 stations throughout the country, are now increasing at a rapid rate. Many leases for such quarters, made several years ago, are now expiring, and must be renewed at increased rates, which makes the aggregate rental charge materially larger.

Notwithstanding such matters, appropriations for the Weather Bureau have remained practically constant. The Bureau is earnestly and successfully striving to maintain the service in the most efficient manner possible, but obviously, under the conditions cited, curtailments and restrictions are unavoidable, if the great service being rendered to the public, for the protection of life and property through its forecasts, is to be safeguarded and maintained with the highest efficiency.

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This country can't afford to let its weather bureau run down. It is too valuable, too necessary. Congress should by all means look into this situation and remedy it without unnecessary delay.-Calumet (Mich.) News, Feb. 4, 1921.

NOTES.

Give science its share.-Refreshing among the requests for appropriations for commercial and warlike purposes was the plea made recently before a congressional committee by Charles Greely Abbot, of the Smithsonian Institution, for "six miles of mountain road, a wireless telephone and a water reservoir to be dug out of solid rock," so that his work of scientific observation at the summit of a mountain in Arizona may be carried on a little more easily. ... [The observations are of solar radiation for computation of the solar constant. The station, which was opened last October, is in the Harqua Hala Mts., Ariz.-one of the least cloudy spots in the United States. ]-Greenville (S. C.) News, Jan. 20, 1921. The winter-killing of plants.-Many plants, observes a writer in the Scientific American, are killed to the ground in winter although the root-stocks which are protected by the soil live and are ready to send forth shoots again the the spring. If it were simply the action of the cold that killed the plant the roots would certainly be destroyed for the ground surrounding them is frozen solid. There is good reason for believing that it is not so much the cold as the excessive loss of moisture that really destroys the vegetable tissue. The upper part of the plant is subjected to a continuous evaporation and this loss of moisture cannot be made good because the roots are in solidly frozen ground....-The Pathfinder (Washington, D. C.), Jan. 1, 1921.

Wintering snipe and rainfall.-Mr. J. T. Nichols reports having seen, for the first time in winter, a Wilson's snipe on Long Island on Dec. 28, 1919 and Jan. 17, 1920. Referring to the Christmas bird censuses published annually in Bird Lore he found that at least one snipe was seen on Long Island at Christmas time in 6 of the 15 reports, 1905-1919. Studying the weather records of the months preceding each of these 6 cases, Mr. Nichols found that mildness of weather could not explain the presence of snipe, for some of the winters (cf. that of 1919-1920) were unusually cold.

"It seems that heavy precipitation in August or October (which are, by the way, the critical months of its southward movement there) is most favorable for the snipe's lingering on Long Island into the winter."-Abstr. from Forest and Stream, May, 1920, p. 251.

Weather reports by wireless.-Government weather reports will be sent out by wireless from the radio station at the Omaha air mail field beginning to-morrow, making it possible for farmers in eastern Iowa and western Nebraska to get them from 12 to 18 hours sooner than at present.....—Washington (D. C.) Post, Feb. 13, 1921.

That the wireless telephone and telegraph weather reports sent out from Madison at 12:30 daily are heard in Texas, Kansas, New Jersey, and on the Canadian Border is indicated by letters received at the wireless experimental station of the physics department of the University of Wisconsin... The tubes used for the transmission of reports by wireless telephone were made by Prof. E. M. Terry, who directs the service....-The Press Bulletin, Madison, Wis., Jan. 19, 1921.

Daily weather reports are to be sent to farmers in all parts of the state by wireless from the Kansas Agricultural college. The farmer receiving the message, either over his own wireless equipment or by 'phone from the nearest station, knows what his immediate course of action should be, whether conditions will be favorable for plowing or planting or harvesting.

Accurate daily weather prediction will mean a good deal to most farmers, especially those remote from ordinary sources of news. But that is only one of the possibilities which lie in wireless service for the farms. By one more medium, more marvelous than telephone or telegraph, the farmer advances from lonely isolation to daily contact with his fellow men.-Moline [Ill.] Daily Dispatch, March 10, 1921.

Brick pavement explodes.-The brick pavement over a 10-mile section of road near Seattle has "exploded" no less than 12 times in the past few years. A short

time ago it blew up the 13th time and threw the rear end of a passing truck up into the air, spilling the occupants out on the ground. Bricks were hurled high and far. It is said that no space was allowed for the expansion of the brick when the pavement was laid. Consequently in hot weather the surface buckles and finally "blows up."-Pathfinder, Nov. 27, 1920.

[The lifting power of water] is vividly demonstrated in the recent experience of Toledo, Ohio. Block paving on a cement sand cushion was washed away during heavy rainstorms. The blocks are being replaced on an asbestos binder course, which provides a much better bottom seal against water. Chicago is also experimenting with asphalt-sand cushions.—Sci. Am., Feb. 5, 1921, p. 103.

The "Rain of Blood."—A curious phenomenon of south France and Italy, occurred recently at Monte Carlo and Mentone. After the downpour ceased the roofs, roads, gardens and shrubs of the Riviera were covered with sticky crimson. The superstitious inhabitants of the gambling metropolis were much terrified. There is, however, a scientific explanation which is perfectly satisfactory. It is that the rain clouds had been saturated with red sand from the Sahara Desert.Sci. Am., Feb. 12, 1921, p. 123.

An "ideal day's work" of a consulting meteorologist.—[Starting from Los Angeles] at 10 a.m., flew to March Field; made my usual 5 minute notes, photos, baro., thermo., and hygro. data for air charting; arrived there an hour later; lectured on "Clouds: their composition and interpretation" illustrated with 100 lantern slides. Lunched with the C. O.; took another plane and flew to the Ranch, 45 miles distant (near San Diego), visited my 26 meteorological stations there, took ship from there to March Field, thence by ship to Los Angeles where I landed in a rainstorm. Motored to the University Club, dressed for dinner and there delivered another meteorological address—all within a little over 6 hours time. Ordinarily this would have taken 2 days and 1 night by either railroad train or motor. I leave on a similar trip to-morrow.-Excerpt from letter of Feb. 7, 1921, by Ford A. Carpenter.

DEATH OF LIEUT. HAROLD T. STEVENS.

It is with regret that members of the Society will learn of the death of Lieut. Harold T. Stevens, who was killed on February 26th at the Naval Air Station at Rockaway Point, N. Y. Lieut. Stevens was piloting a seaplane, and had been in the air about 45 minutes when, in making a turn, the plane went into a tailspin and crashed to the earth near one of the hangars. Both the pilot and his passenger, 1st Cl. Machinist's Mate, E. F. Lindsay were instantly killed and the craft was demolished. The cause of the accident is not known.

Lieut. Stevens was known to members of the Central Office of the Weather Bureau at Washington, for he, with a number of other naval officers, spent June and July, 1920, taking a course in meteorology at that place. He was an experienced pilot, having been attached to the Rockaway station for several years. He was a member of the American Meteorological Society.

HAVE YOU PAID YOUR DUES? IF NOT, PLEASE REMIT.

The appeal sent out with bills for 1921 dues brought in about $630 from some 235 fellows and members during February and the first week in March, or nearly $3 apiece. Dues from about 150 others have been received, totalling approximately $200. It was gratifying to have a considerable number pay double or more in 1921 what they paid in 1920. Since $120 of the $630 recently received is for life memberships, the total funds available for expenses so far this year have been about $710. The 1920 deficit of $200 was wiped out in a hurry. The 1920 list of members and index took $260, the January BULLETIN $110, Monthly

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