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tion, as inferring the probability of actual change ; and those who are interested in this curious subject will find this group well worthy of study. My own impression has the strong confirmation of Knott, who, in July, 1865, noted D (the star in question) " white, with pale dash of blue. D is certainly not so blue as C."
While speaking of coloured light, it may not be uninteresting to note the comparative absence of any decided hue in the larger stars of the Pleiades, as contrasted with many other parts of the sky, for instance, the galaxy region of Sagitta, where most of the leading stars show yellow, or ruddy light.
This opportunity should be taken for a careful study of the colours of the beautiful double star a Piscium (Int. Obs., iï., 55), as to which there is a remarkable discrepancy among astronomers. I have never been able to satisfy myself as to their real character.
The possession of the beautifully-figured 91-inch “With " speculum, already alluded to, leads to the addition of the two following objects as tests for those who may be equally fortunate in optical means.
168. Ò Cygni (2 2579), at the end of the p arm of the cross represented by the principal stars of that asterism. 1":8. 250.6. 3 and 9. Pale yellow and sea-green. Such were Smyth's data for this celebrated but very difficult binary, 1842.56, which saw 2"-5 apart, 1783.72, but single 1802, 1804, as did H. and South 1823, and South 1825. £, however, found it 1":91, 1826.55; Smyth 1"-5, 1837.78; Dawes 1":67, 1865-38; Knott 1":7, 1866.68; while its orbital revolution has carried it through zero from the nf into the np quadrant, from H's 71°:39, 1783-72, by a regular gradation to Knott's 348°31, 1866-68:--the “periastron” being considered to have occurred in 1860. This extremely difficult test I have seen so fairly with 450 in only a moderately favourable state of air, and at a comparatively low elevation, that it may be inferred to be easy under really advantageous circumstances; on the majority of nights it would, of course, be waste of time to look for it. The other object is
169. u Andromedæ; the 4th mag. star next np B, in the line pointing upwards to the Great Nebula. This has a companion at 45" and 115°, 16 mag., which is consequently as severe a test of light as the previous pair is of definition. It is so minute that Smyth saw it but once with his 5.9-inch object-glass, and when the larger star was hidden by a bar in the field.
This most delicate point I have caught up without much trouble, and that while, from a mistake as to the angle, I had so little expectation of seeing it where I found it, that I had been diligently gazing at a spot 90° distant. It was but just steadily visible, but showed itself in the full presence of its blazing companion, so that it may be fairly inferred that this telescope reaches 17, at any rate, of the 20 magnitudes grasped by the 18-inch front view of H.'s metallic mirror. It may be mentioned that this speculum, which, however fine, can at any time be equalled, if not surpassed, by its truly successful maker, shows a black division, with 450, between the components of ry Andromeda, and, with a low power, traces for a long distance both of the remarkable " canals,” or rifts, in the Great Nebula in the same constellation (Int. OBS., iv. 347).
While in this neighbourhood, we may look with a low power about i° f , where we shall find a deep orange single star, and a pretty open pair s of it, all of about 7 magni. tude.
CLUSTER AND NEBULÆ.
46.-4575 Gen. Cat. (w viii. 56) is a charming group of stars of various sizes, to be found 10'n of y Cygni, a little f. H. saw it 5' long, 3 broad, and counted forty stars, two 7.8 mag., the rest 11 mag. In another observation he speaks of stragglers 10-16 mag.
47.—218 Gen. Cat. This curiously-placed and readily found nebula is in the field with B Andromeda, a very strong yellow (Y) star; it lies at a short distance np, and is very easily seen in my reflector. H. calls it pretty bright, considerably large, gradually brighter in the middle.
A more singular object awaits us at no great distance, which we shall point out by the intersection of two straight lines, one drawn from y Andromedce, to y (the central star) in Cassiopea, the other from B Androm., to the glorious cluster in the Sword Hand of Perseus: near the point of their crossing are two. 4 mag: stars, 2° apart; the further n of these is $ Persei, and lo n of this is the nebula we are going to describe.
48.—385, 386 Gen. Cat. (M. 76). This is not a very conspicuous object with ordinary instruments, though it was “ very bright” in H's reflectors; but its most remarkable feature is its double character, consisting evidently of two closely-connected lobes, and resembling a good deal the “Dumb-bell” in miniature, at least as that object was commonly figured before it came under oro careful review. It has been examined by Huggins, with the following truly curious result :-“Both parts of this double nebula give a gaseous spectrum” (as is the case with the Dumb-bell nebula).
“The brightest only of the three lines usually present was certainly seen. The second line is probably also present. I suspected a faint continuous spectrum at the preceding edge of No. 386” (the f nebula).
TRANSITS OF JUPITER'S SATELLITES.
Dec. 4th. II. shadow in transit, 6h. 2m. to 8h. 51m. II. egress, 6h. 15m.-7th. I. ingress, 7h. 54m.-9th. I. shadow egress, 6h.-11th. II. ingress, 6h. 4m., shadow ditto, 8h. 39m.
- 16th. I. shadow in transit, 5h. 37m. to 7h. 56m. I. egress, 6h. 42m. IV. will be in transit while the planet is visible.-21st. III. shadow ogress, 7h. 45m.--23rd. I. ingress, 6h. 21m., shadow, 7h. 33m.-28th. III. egress, 7h. 16m.29th. II. shadow egress, Ch. lm,
Dec. 8th. B.A.C. 830, 6 mag. 8h. 2m. to 8h. 10m.-9th. f Tauri, 4 mag. 3h. 18m. to 3h. 43m.-11th. 130 Tauri. 6 mag. 8h. 49m. to 9h. 24m.-13th. 5 Cancri, 6 mag. 11h, 29m. to 12h. 31m.—28th. B.A.C. 7097, 6 mag. 3h. 49m. to 4h. 49m.
TERMITES, OR WHITE ANTS, IN INDIA.
BY CAPT. R. C. BEAVAN, C.M.Z.S.
In a tropical climate like that of India, it is well known what numbers of destructive creatures, of all sorts and kinds, are rapidly generated in the warmth, and prove, more especially to the naturalist, a source of the greatest trouble and annoyance. Amongst the worst of these may perhaps be classed the Termites, or White Ants; and I propose to give a short account of what seems to be a beneficent provision of nature in the process by which at times they are nearly annihilated. Working in the dark as they do, and always hidden under cover, for they invariably form an exterior tunnel of mud under which to operate when they find it necessary to cross some hard substance that they cannot penetrate (such as iron, or the brick walls of one's house), it is not easy to imagine how they can possibly be got at or destroyed by their natural enemies ; nor, indeed, could they, were it not for the fact that, at a certain stage of existence, the majority of them are obliged to leave their secure underground retreats, and to take to the winged state. It is generally of a dry, calm evening, * frequently after rain, that from various crevices in the walls or stone flooring of the verandah myriads of unwinged white ants are seen to issue, as if forming both the escort and advanced guard of the grand army which, provided with wings, are about to follow. The toads, Bufo melanostictus, and frogs (Sp. incog. nobis) are on the look out for the former, and immediately congregate near the spot. Again and again is the tongue darted out, at every sweep clearing off several ; and there they will stay and continue to feed, until their bloated appearance proclaims that they are full to repletion; when, suddenly, out come the winged host, which, rising with fluttering wings into the air, are met by birds and bats innumerable, and few escape. On the occasion referred to, we noticed the following birds of some twelve different species making sad havoc amongst the winged white ants which were rising from our verandah. Usually rather wild, on this occasion they were perfectly fearless and tame; and the perpetual snap-snap of their beaks whilst hovering in mid-air, and the sudden disappearance of every white ant that rose beyond a certain height from the ground, was a curious sight to see. The birds observed on this occasion were:-1st, the black-headed oriole, Oriolus melanocephalus ; 2nd, the common king crow, Dicrurus macrocercus; 3rd, the tree-pie, Dendrocita rufa; 4th, the magpie robin, Copsicus santaris ; 5th, actually a small owl not usually diurnal in its habits, Athene Brahma; 6th, the common babbler (or “seven brothers” of the natives, because they generally associate in that number), the Malacocircus ter. ricolor of naturalists; 7th, the scarlet-vented bulbul, Pycnonotus pygaus; 8th, the common grey-necked crow, or jackdaw of India, Corvus splendens; and we think we also observed the green bee-eater, Merops viridis; whilst higher up in the air might be seen the common pariah kite, Milvus govinda, and the Brahmin kite, Haliastur Indus, swooping down on those unfortunates which escaped the birds at lower elevations. In addition to these may be mentioned the common Indian swift, Cypselus affinis, and, in fact, all birds which feed on insects would, we imagine, readily do the same. As it gets dark, the ants increase in number, and the birds, already filled to repletion, gradually go off to their roosting-places, and it seems as if they (the ants) were going to escape after all. But just at this moment another more terrible enemy makes * The following notes were made at Barrackpore, on the 8th November, 1864.
The air is suddenly filled with bats of all sizes ; backwards and forwards they shoot without any intermission, and so eager are they in pursuit of their prey that we have frequently caught them in a butterfly net by simply holding it out from the top of the house. As may be imagined, these foes grant but little quarter, until the whole winged cloud of white ants is totally annihilated. Scarcely one has escaped to found a new colony.; and, as night closes over the scene, they seem to be aware that wings are after all of little
Another note regarding them. We have frequently, of an evening, observed what seemed to be water-beetles in our tank and others in the neighbourhood. They kept spinning round and round like a Catherine-wheel, disturbing the water within a radius of fourteen inches. Occasionally one was taken down by a fish, or the species of skipping-frog, so ably described by Dr. Adams in his “Naturalist in India," page 16, would suddenly rush out from the bank, seize one, and devour it. Determined to secure one of these beetles, one evening, for our English correspondents, and being, moreover, rather puzzled as to why we only saw them spinning round of an evening, we made a capture, and, to our no small disgust, discovered that they were only winged white ants which had fallen into the water. The reason they are only seen of an evening is of course explained by the fact that white ants only come out in the winged state during that time.