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apparatus, such, for example, as Seismic instruments, which is pretty certain to be procured before very long. I propose also to provide a small room for the Electrograph, which will be referred to farther on. I have added, at Mr. BOWDLER's suggestion, an upper storey, to be appropriated as quarters for the Director. I recommend that the building be constructed of red bricks, the walls of the lower storey being made 1 ft. 9 in. thick, and those of the upper storey 1 ft. 2 in. thick. The rooms should be 15 feet high, from floor to ceiling, and the roof be made as flat as possible, in order that it may be utilised for some of the meteorological apparatus. Especial care must be given to protection of the building against lightning, for which purpose one conductor should be placed at each angle of the main block, and the points carried at least eight feet above the parapet, the earth ends being sunk below ground until permanently damp soil is reached.
In laying out the building on the ground, it will be important to obtain accurate orientation, for which purpose I suggest that Polaris be observed with a theodolite at one of its culminations, and a meridian line carefully marked at the observation. The transit-room will need vertical shutters about two feet wide, opening in the north and south walls from a height of four feet above the floor, and extending to the roof; also roof-doors of the same width, so that there may be a clear view of the meridian from the south to the north horizon. The collimator may be placed on a brick pier about fifteen feet to the north of the transit-room, a small room or hut six or seven feet square being built over it, for protection from the weather. It should be approximately horizontal with respect to the transit-instrument.
Piers, isolated from contact with the surrounding soil or any parts of the building, will be needed for the transit-instrument, the electrograph, the collimator, and each of the two clocks. These should be built of red bricks, in cement, and be carried down to firm ground, at a depth of not less than four feet in any case, there resting on good foundations of cement concrete. The largest will be those for the transit-instrument and electrograph, which may measure about six feet by three feet. For the clocks the dimensions will be very much smaller. All of them had better be left unfinished at the floor-level until the instruments and clocks arrive.
A building on a plan somewhat as shown in the accompanying tracing will probably answer as well as any for the present purposes of the Observatory. Lest it be thought that the space provided is somewhat more liberal than is necessary, it may be well to bear in mind the great heat of the summer weather, as well as the facts that ample room will be needed for presses for stores, stationery, records, &c., and that the requirements as to space in an establishment of this kind are certain to grow year by year. If at a future time it should be decided to increase the equipment, the east and west wings could be extended so as to accommodate a Photoheliograph for the record of sun-spots, as suggested by His Excellency the Governor, and an Equatorial telescope. It would be necessary, in this case, to raise the equatorial sufficiently high to obviate any serious interruption of the sky view by the upper storey of the main block; and, for architectural symmetry, the photoheliograph might be similarly raised. But, if a Siderostat in connexion with a fixed telescope should be preferred for gazing purposes to an equatorially mounted instrument, no such elevation would be needed. A building of the kind above suggested would probably cost, with piers, &c., about $10,500, to which $500 must be added for furniture and fitments. A small additional building, to contain quarters for a caretaker, servant and coolies, with a store, workshop, kitchen and other offices, and connected with the main edifice by a covered way, would cost say $2,400 more. Both of them may be at once designed in detail, and proceeded with, should the scheme here proposed receive the approval of the Government.
II-Meteorology
The proposal to establish a meteorological branch of the observatory, under skilled management and supplied with the best modern apparatus, commands approval for two reasons. In the first place, as Dr. DE LA RUE has indicated, such an institution will furnish the science with valuable and much needed data, from a locality well suited for the observation and collection of facts appertaining to certain phenomena of special interest. Secondly, it cannot fail to have a direct and practical value, as being the means of affording security, by its predictions and weather warnings, to life and property, in seas navigated by vast numbers of native and foreign vessels, but subject during four or five months of the year to rotatory storms of appalling violence and danger.
Its operations, like its purpose, will be twofold. There will be, to begin with, the systematic observation and record of the ordinary phenomena of pressure, temperature, humidity, rain, sunshine,
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wind and hydrometeors, such as are usual in observatories of the first order; together also with observations of atmospheric electricity.
So lately as last February, Dr. WARREN DE LA RUE furnished the Colonial Office with a list of the instruments necessary for these purposes in a first-class meteorological observatory. The list comprises a Barograph, a Thermograph, an Anemograph, a Rain-gauge, a Sunshine Recorder, and an Electrograph; together costing about £397.
Of these, the Barograph, or self-recording barometer, will be accommodated in the Magnetic basement, to be presently described.
For the Thermograph-i.e., self-registering (photographic) dry and wet bulb thermometers-a special hut and shed will have to be put up in the grounds of the observatory. This may, however, be left until the instruments arrive. The Thermograph, it will be observed, does away with the necessity for maximum and minimum thermometers, as the changes of temperature are recorded unceasingly.
The Anemograph, or self-recording Anemometer, is an instrument the best and newest forms of which are constructed to register continuously the direction, pressure and velocity of the wind. We are not told by Dr. DE LA RUE what kind will be sent. A small turret, to carry the vane, &c., for the instrument, of whatever pattern, may be erected centrally over the front verandah roof of the main building, and the spindle be carried through the roof to the registering apparatus placed in a small chamber or compartment on the upper verandah, as shown in the drawing. The turret must be provided with a lightning conductor.
The Rain-gauge, to judge from the high price (£60) set against it in the list, is doubtless a self-recording instrument, or pluviograph. At Greenwich, an Oster's Anemometer and Rain-gauge form a joint apparatus, by which wind and rain are registered on the same sheet of paper. This instrument needs no special provision beforehand.
The Sunshine Recorder is a contrivance for marking and measuring the duration of sunshine. The instrument in use at Greenwich consists of a solid glass ball four inches in diameter, supported in a hollow hemispherical bowl of three inches' radius, the two surfaces being separated from one another by a space of an inch. The rim of the bowl is marked like a sundial, and the interior surface is lined with a strip of prepared mill-board. Whenever the sun shines out, its rays, brought to a focus by the glass ball, burn a mark on this strip. The intervals and interruptions of sunshine are thus recorded. This instrument may be set up on the roof of the main building, for which purpose no special preparations are needed.
The Electrograph of Dr. DE LA RUE's list, though not described, is doubtless a THOMSON'S Quadrant Electrometer, fitted for photographic self-registration. It has been shown that I have provided a small room for it on the ground floor of the main building, the window of which can be darkened to the extent required. The collector for this instrument may be attached to a small mast on the roof, above the room; and the wire or rod be carried thence to the instrument, the pier for which should be capped with a slate or marble slab.
The whole of the above, it will be noticed, are autographic instruments, and need only occasional attention, for changing the record-sheets, pointing the pencils, &c. The labour of observation is thus reduced to a minimum.
The second branch of work appertaining to the Meteorological Department will be the observation and collection as far as possible of facts and phenomena relating to typhoons, both for the protection of marine interests and for the purpose of contributing bit by bit to our knowledge of a subject at present but little understood. It will include also the giving attention to the phenomena of the monsoons.
For weather warnings, the telegraphic cables connecting this port with others on the coast, and with Manila, will furnish most valuable aid. The Manila cable will be of special service in this respect. Past observations seem to show that the typhoons which sweep the Southern China sea for the most part originate in a region the centre of which is situated about a thousand miles (in round numbers) to the south and east of the Philippines. Of those which take Luzon in their course, some make for Hainan and the Gulf of Tonquin. Others pursue a more northerly direction, towards Formosa and