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Connecticut and upper Androscoggin, must get along with 35 inches or less. The Lake Champlain lowland, in the rainshadow of both the Green Mountains and the Adirondacks, and with the summertime reducing effect of the cool lake, has the lowest rainfall, from 35 to less than 30 inches. The absolute maxima are generally a third again as great as the averages, while the minima are about a third off.

Acknowledgements are due the U. S. Weather Bureau and the Massachusetts Department of Public Health which supplied the data for the 45-year period, 1881-1925, used; to J. Henry Weber who compiled, averaged and adjusted most of the data, and prepared the maps and detailed discussions for the annual and seasonal rainfalls of New England as a whole and for the monthly rainfall of southern New England; to Dr. Gragg Richards who reduced, mapped and discussed northern New England, and to the New England Water Works Association which published these studies in its Journal (vol. 42, 1928) and which, with additions, will bring these out in book form, in 1929.

Discussion. Mr. Tarr remarked that the monthly rainfall type of the White Mountains was like that of the prairies. Dr. Brooks, however, called attention to the not inconsiderable rainfall in winter in the White Mountains which distinguished the type here from that of the prairies, where the winter rainfall was considerably less. Professor Ward, citing the distinct difference between the type with summer maximum in the interior of New England and that with winter maximum on the coast confessed that he had probably been guilty of simplifying too much. However, he saw some justification for a smooth curve for New England showing approximately even distribution through the year, especially in teaching so complex a subject as the climatology of the United States in a limited time. It was difficult to know at what degree of local differentiation to stop when picking rainfall types. Mr. Tarr asked why it was so much more windy on Mt. Washington than on Pikes Peak. Mr. Fergusson replied that in addition to Pikes Peak being farther from tracks of numerous storms, it was on the eastern margin of a much broader and higher mountain region than Mt. Washington. Mt. Rose on the western margin, in the Sierras, Mr. Fergusson had found to be much windier than Pikes Peak and not much less windy than Mt. Washington. The effect of the mountain itself on wind velocity, Mr. Fergusson said he had found to be considerable. Velocities on Mt. Washington were 30 per cent. or more greater than those in the free air at the same level. Concerning the marked summer maximum of precipitation on Mt. Washington, Mr. Fergusson suggested that the winter precipitation is mostly snow which is so drifted by wind that accurate measurements near the summit are impossible.

By letter, Mr. Fergusson added this amplification: "Drifting affects all methods of measurement; the average of several measurements of depth after snow has fallen is better than using the amount in a "catch"

gauge, but, on Mt. Washington, it is impossible to find a place where the snow falls undisturbed by wind. The ridges and slopes may be swept bare of snow or covered deep with snow blown from a distance."

MOUNTAIN RAINFALL MEASUREMENTS IN NEW HAMPSHIRE A novel campaign of mountain rainfall measurements in New Hampshire was initiated in June, 1928, by Prof. J. W. Goldthwait, State Geologist. Rainfall records had previously been kept on only one mountain in the state-the summit of Mount Washington, where measurements were made for sixteen years or so, between 1871 and 1890. The average rainfall there was found to be over 80 inches a year, or twice as much as over New Hampshire generally.

In the present undertaking an effort has been made to secure records at every place on a New Hampshire mountain where a man is known to be available daily or for some part of each day during the summer. Special interest is felt in the highest and most central group of stations, on the Mount Washington range, consisting of the huts of the Appalachian Mountain Club, at Mount Madison and the Lakes of the Clouds, the Halfway House on the Mount Washington summit road, and the Summit House itself, with comparison stations at the foot of the range at Randolph, Peabody River guard station, Pinkham Notch hut, and Notchland, in Crawford Notch. Similar groups of mountain and valley stations have been established elsewhere, so that much instructive information will doubtless be obtained concerning the relative amounts of rain falling at different altitudes, the effects of topography and exposure, etc.

Most of the observers are forest fire watchmen of the state forestry department or guards of the U. S. Forest Service. Besides these temporary stations, the permanent stations of the U. S. Weather Bureau have furnished data for comparison.-C. Fitzhugh Talman, in Why the Weather? (Science Service).

Object of the investigation. The great November floods of 1927, originating to a large degree in the mountains, led Professor Goldthwait to propose these rainfall observations and the State Highway and Forestry Departments and others to endorse it and assist.

Equipment, number of stations, methods. Ordinary pails, 10%1⁄2 inches in diameter at the top, and ordinary spring scales, with pound and ounce divisions up to 20 pounds, constituted the simple end inexpensive equipment distributed to the 50-odd new stations established. The pails were set on the ground in open places and held firm by stones piled round them. Including the permanent stations reporting to Professor Goldthwait during the summer there was a total of 82 rainfall stations. The instructions to observers called for one or more observations daily, including one about 5 p. m., the report to be rendered weekly in pounds and ounces. Care was urged to minimize losses by evaporation. These pail gauges where near permanent stations gave results closely in line with those of the standard gauges. On the higher mountains, however, the effect of

the wind in probably blowing rain from the pails was noted as a not inappreciable source of error. A general statement, with photographs and a map of stations appeared in New Hampshire Highways for July, 1928.

Monthly summaries of the reports appeared with commendable promptness in mimeographed form. The first, for June, described in five pages the observational network that had been established and the results obtained for the month. The daily rains were related by Prof. Goldthwait to the low pressure areas that affected this region, and a map of the paths of the rain-bringing lows is included in this round-robin to the observers. The July report had a page of discussion, including a summary of the rainfall distribution and its relation to the lows that passed, and four pages of tables of the daily rainfalls, including a rainfall map of the state for July, 1928. A special letter late in August gave the names, co-operators and locations (map) of the 82 stations in the state. The fourth bulletin covered August rainfall; the fifth, that of September, and the sixth and last for 1928 was simply a table of the October rainfall for those stations that were still open.-C. F. B.

The September, 1928, issue of New Hampshire Highways contains an interesting article by Prof. J. W. Goldthwait on "Summer Rainfall on New Hampshire Mountains." Volunteer observers during July and August were measuring and reporting daily rainfall to the State Highway and Forestry Departments. These records contributed much to the knowledge of the distribution of rainfall and the influence of topography. As most of the summer rainfall is the result of local showers and thunder storms there is little uniformity in the distribution of rainfall over the whole state. Within narrow limits, however, the influence of altitude on rainfall was pronounced. Thus during July and August, 1928, the mountain tops showed from one and one-half to two times as much rainfall as the valleys. Over greater distances mere altitude did not this past summer mean greater rainfall, for Monadnock (alt. 3166 ft.) received 19.21 inches, while Washington, nearly twice as high above sea level got only 15.26 inches. Very interesting was the distribution of rainfall at nine stations about Mt. Washington. The summit received the largest amount, but there was great irregularity at the other stations and by no means a uniform decrease in rainfall with decrease in altitude.-N. H. B.

The September rainfall showed an interesting contrast to some of the summer falls, in that a general northeast storm brought slightly more (measured) rainfall to Randolph, a windward valley station, than to the stations on the Presidential Range nearby. A summer southeaster had brought most rain on the southeast exposure.

The rainfall observing campaign will be continued in 1929.

Professor Goldthwait deserves the highest commendation from climatologists for his initiative and energy in providing such an ample body of new data on the summer rainfall of a portion of our northeastern mountain region.-C. F. B.


During the past two years a compilation of temperature data for New England has been under way by the Graduate School of Geography of Clark University and the Boston and Portland offices of the U. S. Weather Bureau, Messrs. G. A. Loveland (Section Director) and G. W. Mindling, officials in charge. Forty-year (1885-1924) monthly and annual normals, including those of shorter record stations adjusted to the forty years, have been prepared for southern New England and many maps constructed. The items included are: mean daily maximum temperature, mean daily minimum, mean daily temperature, and extreme monthly maxima and minima. The tables for northern New England are nearing completion.-Charles F. Brooks.


The publication of Dr. Humphreys' Presidential Address in this issue of the BULLETIN, as stated in the January number, is impracticable. It will appear, however, in the March issue.

The Friday morning session convened at 9:37 a. m., with Professor Ward in the Chair, and Professor Hobbs gave the two opening papers on clouds photographed in Greenland and the Chicago-Stockholm flying route via Greenland. In addition to their features of meteorological interest his slides showed beautiful cloudscapes, and the magnificent scenery of part of Greenland's fiorded coast. At the conclusion of the appreciative discussion, the Secretary took the occasion to announce that, as a result of recent balloting by the Council, Dr. Hobbs had been elected a fellow of the American Meteorological Society.

Professor McAdie's illustrated presentation of certain meteorological hazards to aviation followed, and, after a brief recess, his demonstration of a number of novel instruments. That of chief interest was an instrumental answer to the question "How fast and how long should a psychrometer be whirled?" The ventilation of an ordinary psychrometer is insufficient. On a metal arm a meter long, Prof. McAdie whirled the wet and dry bulb thermometers at a speed of 10 or more meters per second for a definite number of revolutions marked at the end by the ringing of a bell near the handle. A speed of over 13 meters does not give added value. The suspense of momentarily expecting the thermometers swinging in such a large circle to be dashed to pieces against the ceiling, wall, floor, desk or table, made the whirling seem long. But the demonstrator carefully brought the experiment to a successful conclusion and read his hygrometric data direct from the thermometers without the use of tables for reduction. The special advantage is the control of ventilation from 3 to 13 m/s. This instrument is made by Negretti & Zambra. An improved direct reading nephoscope, a multiscale thermometer, and

other instruments were also exhibited. Descriptions of these have appeared in the Annals of the Blue Hill Observatory.

Three other papers: on small balloons for instruction in meteorology, on the preliminary fulfillment of the British Isles test rainfall predictions, and on the duration of rainfall at Baltimore, concluded the morning program, adjournment coming at 12:10.

The Friday afternoon session, as previously noted, was a joint one, at which Dr. Humphreys presented a meteorological paper, "Some Examples of Outdoor Physics." With the aid of lantern slides he presented the Ekman spiral-the drift of water under the influence of a steady straight-away wind, and the effect of surface drag and air turbulence on the direction and velocity of the wind at different heights. He also explained, with diagrams, the formation of the rainbow, including the supernumerary bows; the horizontal rainbow; the phenomena of mirage, both as applied to light and to sound; the effect of wind on sound; the cause of flickering in the case of lightning; the cause of "musical" thunder, and a few other things equally well known to a few and equally unknown to the many. The main point of his paper was evident: namely that there are many examples of real physics outside the walls of a laboratory.

Abstracts and discussions of Professor Hobbs' papers, Professor McAdie's aviation hazard papers, and of the others presented during the morning session are published below. The Saturday morning concluding session will be presented in the March Bulletin.-C. F. B.


By David B. Potter, Photographer of Third Greenland Expedition of the University of Michigan

(Presented by WILLIAM H. HOBBS, Director)

The clouds observed at the Greenland station of Mount Evans have characters somewhat different from those observed away from the great ice-caps. There is a marked dominance of high level clouds and as striking an absence of the low stratus varieties. The cirri and related forms present a great variety which is only partially represented by this collection. Of special interest also are the foehn clouds which sometimes cover the entire sky and at other times appear in isolated groups consisting of thin sharply lenticular units built up on a vertical axis resembling piles of coins. Also of great interest are the convectional clouds which develop almost daily along the south margin of the fjord, which persist in position for long periods and send up vertical columns from separated centers.

These cloud pictures were all photographed by Mr. Potter within the month of August, 1928, and all within a few miles of the base of the University of Michigan Expedition. They are to be supplemented later by other pictures taken at different periods of the year.

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