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19. During my absence on leave from the 28th May to the 26th December, inclusive, after eleven years continuous service in the Colony, Mr. J. I. PLUMMER. Chief Assistant, took charge of the astro- nomical and magnetic observations, including the time-hall, and Mr. F. G. FIGG, First Assistant, attended to weather-forecasts and storm-warnings and superintended the meteorological work. The way Mr. FIGG discharged these duties, which are of considerable importance to shipping, during my absence, is deserving of the highest praise, and calls, I respectfully submit, for some reward from the Government. Miss A. DOBERCK, Assistant Meteorologist, attended to maritime meteorology and made weather maps. Mr. Ho To SHANG, Second Assistant, attended to the monthly and annual weather- reports, in which he was assisted by two native computers, who also made hourly observations day and night and attended to electric and photographic work. Some of the instruments suffered during my absence from various causes, but I expect to have them in as good order next summer as they were last spring.

20. Observations of magnetic declination and horizontal force were made by Mr. PLUMMER and reduced by Mr. FIGG with the unifilar magnetometer Elliott Brothers, No. 55, and the dips were observed with dip-circle, Dover No. 71. The methods adopted in making the observations and in determining and applying the corrections are explained in Appendix G of Observations and Researches made in 1885: "On the verification of the unifilar magnetometer Elliott Brothers No. 55." The value of log K was 3.44901 at 25°. The value of P was +8.360. The mean value of the magnetic moment of the vibrating needle was 0.45363 in English units and 592.24 in C. G. S. units.

The times of vibration exhibited is the table are each derived from 12 observations of the time occupied by the magnet in making 100 vibrations, corrections having been applied for rate of chronome- ter and are of vibration.

[The observations of horizontal force are expressed in C.G.S. units (one centimetre, one gramme, one second), but the monthly synopsis exhibites X, the horizontal, as well as Y, the vertical, and total forces, which have been computed by aid of the observed dips, and their value is also given in English units (one foot, one grain, one second) and in Gauss's units (one millimetre, one milligramme, one second.]

21. 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-guage is 105 feet above M.S.L., and 21 inches above the ground.

22. 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, as measured (at two minutes to the hour named) from the baro- grams.

Tables II. and III. exhibit the temperature of the air and of evaporation as determined by aid of rotating thermometers. Table II. exhibits also extreme temperatures reduced to rotating thermometer. 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 estimated 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.

After the typhoon of October 5th to 6th the axis on which the cups revolve was found to be broken just above the point where the cups are fixed. This is believed to have occur- red at about 4.30 p. on the 5th. The velocity recorded for 5 p. (4.30 p. to 5.30 p.) was only 46 miles and during this interval the wind was estimated to be at its worst and to be blowing with full typhoon force. The velocity recorded for 6 p. (5.30 p. to 6.30 p.) was 67 miles and during the hour the wind was also estimated to be of typhoon force, but per- haps somewhat less violent than during the preceding hour. The values 85 and 80 miles have, therefore, been substituted for these two hours respectively in place of those actually recorded. The values for subsequent hours agree very well with the estimations of force on