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14. The cisterns of the barograph and standard barometers are placed 109 feet above M. S. L. The bulbs of the thermometers are rotated 108 feet above M. S. L., and 4 feet above the grass. The solar radiation thermometer is placed at the same height. The rim of the rain-gauge is 105 feet above M. S. L., and 21 inches above the ground.
15. The Monthly Weather Reports are arranged as follows:-
Table I. exhibits the hourly readings of the barometer reduced to freezing point of water, but not to sea level nor for gravity, as measured (at two minutes to the hour [mean time] named) from the barograms.
Tables I1. and III. exhibit the temperature of the air and of evaporation as determined by aid of rotating thermometers. Table II. exhibits also the extreme temperatures reduced to rotating thermometer by comparisons of thermometers hung beside them. Table III. exhibits also the solar radiation (black bulb in vacuo), maximum temper- atures reduced to Kew arbitrary standard.
Table IV. exhibits the mean relative humidity in percentage of saturation
and mean tension of water vapour present in the ar in inches of mercury, for every hour of the day and for every day of the month, calculated by aid of BLANFORD's Tables from the data in Tables II. and III.
Table V. exhibits the duration of sunshine expressed in hours, from half an hour before to half an hour after the hour (true time) named.
Table VI. exhibits the amount of rain (or dew) in inches registered from half an hour before to half an hour after the [mean time] hour named.
It exhibits also the observed duration of rain.
Table VII. exhibits the velocity of the wind in miles and its direction in points (1-32.) The velocity is measured from half an hour before to half an hour after the hour [mean time] named, but the direction. is read off at the hour.
Table VIII. exhibits, the amount (0-10), name (HOWARD'S Classifica-
tion), and direction whence coming of the clouds.
Where the names
of upper and lower clouds are given, but only one direction, this refers to the lower clouds. With regard to the names of clouds, nimbus (nim) is entered only when the rain is, seen to fall; when Do rain is seen to fall cumulo-nimbus (cum-nin) is entered. This name indicates clouds intermediate between cum and nim. Cumulo- stratus (cum-str) is the well-known thunder cloud, while strato- cumulus (str-c) signifies a cloud intermediate between stratus and cum.
Sm-cum means alto-cumulus.
I
Table IX. exhibits for every hour in the day, the mean velocity of the wind reduced to 4 as well as 2 directions, according t strictly accurate formulæ, and also the mean direction of the wind. Below this is printed a list of the phenomena observed.
16. The following annual Weather Report for 1904 is arranged as follows :- Table II. exhibits the mean values for the year (or hourly excess above this) obtained from the monthly reports. The total duration of rain was 745 hours. There fell at least 0.01 inch of rain on 137 days.
Table IV. exhibits the number of hours during a portion of which at
least 0.005 inch of rain (or dew) was registered.
Table V. exhibits the number of days with wind from eight different points of the compass The figures are obtained from the mean daily directions in Table VII. of the monthly reports. Days with wind from a point equidistant from two directions given, are counted half to one of these and half to the other, e.g., half of the days when the wind was NNE. are counted as N, and the other half as NE.