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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 named) from the barograms.
Tables II. and III. exhibit the temperature of the air and of evaporation as determined by aid of rotating thermometers. Table I. 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 temperatures 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 air 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 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 named, but the direction is read off at the hour.
Table VIII. exhibits the amount (0-10), name (Howard's classification), 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 no rain is seen to fall cumulo-nimbus (cum-nim) 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-cum) signifies a cloud intermediate between stratus and cum. Sm-cum means alto-cumulus.
Table IX. exhibits for every hour in the day, the mean velocity of the wind reduced to 4 as well as 2 directions, according to strictly accurate formula, 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 1902 is arranged as follows:-
Table III. exhibits the mean values for the year (or hourly excess above this) obtained from the monthly reports. The total duration of rain was 678 hours. There fell at least 0.01 inch of rain on 132 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.
Table VI. exhibits the number of days on which certain meteorological phenomena were registered, and also the total number of thunderstorms noted in the neighbourhood during the past year.
Table VII. shows the frequency of clouds of different classes.
Table VIII. is arranged as last year.
Table IX. exhibits the monthly and annual extremes.
Table X. contains five-day means.