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instrument will be actuated mechanically and, hence, will be free from the caprice of electric batteries. Mr. Fergusson designed and constructed the meteorograph placed by Harvard on El Misti, Peru, (altitude 19,000 feet), and has been conducting observations of the weather at Mount Washington.

OBSERVATIONS

Despite the lack of long range instruments, observations have been continued by means of bi-weekly or monthly visits throughout the year. On one occasion, March 28-29, 1907, the party, consisting of Professor Frandsen and the writer, failed to reach the summit after a prolonged struggle with soft snow, in which the Canadian snow-shoes broke beneath the strain. This failure occurred almost exactly on the anniversary of the failure of two consecutive attempts the year before.

1. CLIMATOLOGY OF MT. ROSE (Altitude 10,800 feet)

The most valuable results of these observations is a climatological record extending over two years. This record, though necessarily fragmentary on account of the inadequacy of the instruments, still

TABLE I. MINIMUM AND MAXIMUM TEMPERATURES
APPROXIMATELY BY MONTHS AND SEASONS
Mt. Rose (altitude 10,800 feet)

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1. The record for May 28-June 15. 1907. of minimum 12° F. and maximum 59° F. and other occasional records since gathered show the steadiness of the climate on Mt. Rose.

2. Estimated.

record of wind velocity will be accurate and that only the record made during the waning of the storm will be subject to correction. With further observation the factor of correction may perhaps be determined.

The perfecting of an automatic meteorograph which will successfully record the weather conditions at high altitudes is the necessary antecedent to a more thorough knowledge of mountain meteorology, and it is at present the most important problem of the observatory.

In PLATES XII and XIII the meteorograph is shown under test on the University campus. In PLATE XIV the shelter which has been built to house it is shown in position on Mt. Rose. The cost of both shelter and meteorograph will approximate $500, a modest sum when the time and labor involved are considered.

represents the general characteristics of the temperature at the summit of Mt. Rose. So far as possible, the tables will be arranged by months and seasons.

The record of -2°F. for August 4-September 4, 1905, is probably erroneous, the needle having been shaken by a violent thunder storm before the shelter was more rigidly anchored. Yet the needle should have been shaken upward to judge from the inclination of the tube.' The succeeding reading of September 4-October 7 is approximately correct, if the record of -1°F. obtained at Bodie (altitude 8500 feet) on September 30 may be considered a criterion. With these exceptions the temperatures of the four seasons are approximately the same for both years.

However, to cite the above maxima and minima without further modification would be misleading, for the minima represent by no means the general tendency of the weather any more than do the maxima. The former are largely confined to periods of storm just as the latter represent the effect of the sun. TABLE II, prepared to illustrate an article on Summit Temperatures in Winter in the Sierra Nevada, will represent the general phases of the temperature throughout the year. The mean and the minimum temperatures are given, the latter having special significance for the forecasting of frosts on the lowlands.

In this table the periods of fair weather are separated from those of storm, and the hours of night during fair weather apart from those of daylight. In periods of storm the difference in temperature between day and night is almost negligible. The table, being fragmentary, can be used specifically only for the dates mentioned, though it is representative of the rest. The chronological arrangement will indicate the relative frequency of fair weather and of storm. The period covered is that of snow fall and snow fields on Mt. Rose.

2. PLANT ENVIRONMENT

Some assistance has been rendered Dr. P. B. Kennedy, Station Botanist, in the study of plant environment on Mt. Rose. The climatological data have been used by him in a preliminary study of the flora of the mountain, which he has been classifying during the past two seasons. While more complete climatological data are desirable accurate knowledge of the effect of low temperature on flower and fruit can be obtained only by the continued presence and personal observation of the botanist. One observation of possible value has, how

1. H. F. Alps, formerly Acting Section Director of the Nevada Section, U. S. Weather Bureau, reports a similar experience, in which the needle was shaken upward against the force of gravity.

2. Botanical Features around Reno, P. B. Kennedy-Muhlenbergia, Vol. III. No. 2, February, 1907, pp. 17-32.

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TABLE II.--TEMPERATURES IN FAIR WEATHER

AND IN STORM

Mt. Rose (Altitude 10,800 Feet)

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