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THE HONGKONG GOVERNMENT GAZETTE, 18TH APRIL, 1863.
For this purpose, inquiries should be instituted at once, into the circumstances accompanying the fall of any meteoric mass, and into the state of any such mass when it has fallen; and as regards any meteoric appearance in the sky, it will be found advisable, after noting carefully the point in the heavens at which the meteor made its appearance, to give, as accurately as possible (see Note), the direction of its track and the point at which it disappeared.
Where it is possible this track should be delineated on a diagram, as explained in the note.
The points to which especial attention is invited are enumerated in the following two series of inquiries.
The first series relates to meteoric phenomena in the heavens, and their association with the fall of aërolitic matter to the earth.
1. Note the exact position of the observer, according to latitude and longitude.
2. Give the hour, day of month, and year.
3. Give the apparent size of the luminous ball, as compared with the full moon.
4. Its shape; whether round, pear-shaped, or otherwise; and, if elongated, in what direction.
5. It is particularly important to note the place where the meteor is first seen (as at A, see Note) like a star, and from which, as it moves, it may appear to be increasing in size.
6. State the duration of the phenomena; and,
7. Whether the ball again dwindles away to the semblance of a star, and then disappears, or whether it retains to the last its full size, or then, as is often the case, divides into several balls or stars.
8. Give the colours.
9. Record any facts that can be gathered concerning detonations or noises, accompanying the other phenomena.
10. Endeavour to collect statements relating to the actual fall to the earth of any solid bodies.
11. Do they consist of stone, or iron, and is there anything peculiar in their structure?
12. Was the body red-hot, or warm, or did it exhibit evidence of having been warm outside and cold within? as, for instance, by being hot at first and intensely cold afterwards?
13. It is desirable, further, to notice the depth to which, and the direction in which, the aerolite has penetrated the earth; also to state the nature of the soil, the effect produced on it by the aërolitic mass, and the position in which the aërolite was found to be lying in the ground.
The second series of inquiries has for its object the acquisition of a more precise knowledge regarding the aerolite s themselves. For this, it is important to preserve, and to collect, for the purposes of analysis and of scientific comparison, as many of these bodies as possible; and the following suggestions are offered in the hope of promoting this object.
1. Endeavour to get the meteorolites as soon as possible after their fall, to prevent them from being injured, fractured, or wetted.
2. If not entire, try to procure fragments.
3. Should persons or museums not be willing to part with them for the British Museum, then procure drawings, photographs, models, or casts; accompanied by an accurate description of their colour, their external lustre, and, if broken, the nature of the substance or substances exhibited by the fracture and especially be careful to describe the form of the aerolitic mass, whether angular or rounded, whether prismatic, or otherwise exhibiting an approximation to any geometrical figure. Also, state whether its surface be smooth, or marked by any peculiar kind of roughness, or pitted with hollows.
4. Catalogues of the meteorites in local museums are very desirable, with statements of their weights, and also the time of, and other facts accompanying, their fall, as detailed above.
5. From masses of iron or stone still lying on the earth, and too large to be brought away, detach specimens of good size, say from 20 lbs. to 50 lbs. weight, and collect all obtainable information, with detailed descriptions, drawings, measure- ments, historical accounts, &c.
6. Iron meteorites should always be cut with a steel saw and emery.
The Collection of Aerolites in the Mineral Department of the British Museum is now, as regards the mass and size of the specimens, the finest in the world, and any person who may be in a position to contribute additional specimens is re- quested to accompany them with an attestation as to the weight of the specimen, and facts regarding it such as the senders may be in a position to state on their own authority, or as may have come to them on authority which they have reason to accept as reliable.
NEVIL STORY-MASKELYNE.
NOTE.-The delineation of the track of the meteor on paper is very desirable as presenting greater accuracy than a merely verbal description. A practical and simple method of doing this consists in noting down the tracks of meteors, or "fire balls," upon a projection, like the diagram, of a hemiorama, taken from the place of the observer, noting the altitudes and the azimuths corresponding to meridians and parallels of latitude. The accompanying sketch expresses that
N.
90°
60°
30°
Horizon.
N.
N.E.
N.E.
E.
E.
S.E.
S.E
S.
90°
60°
30°
Horizon.
S.
to an observer turned towards the East, the meteor appeared in the N.N.E. at an elevation of 75°, and fell down to the S. E., where it disappeared only 10° above the horizon.
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