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indicated by it. This, however, would not give even the comparative measure exactly, because a difference in the velocity of the rising or falling of the earth's surface would affect the instrument."
Were observers always to employ vessels of the same dimensions, as for instance hemispherical cups of earthern-ware, painted white interiorly, having a diameter of ten and a depth of five inches fixed on a standard a foot in height, and filled for two inches of their depth by a fluid as nearly as possible of the same tenacity as treacle, the observations made at different points would be comparable with each other, and it would perhaps be a simpler method of estimating the intensity of the shock, than either of those proposed by Professor Babbage, were a graduated semi-circular arc to be fitted inside the cup, and the difference between the highest and lowest points of the wave caused by the shock, to be observed from it. This difference would be in a certain degree proportional to the intensity, being greater, as it was greater and less as it was less; and although it would after all be but a rough approximation, still it would be interesting, and worthy of remrak.
The discussion of all local observations ought to be undertaken by one person, who by combining them properly, would be able to deduce general results of the highest interest. It may be long ere we can find any means of protection against the appalling, and apparently irresistible effects of such convulsion as Earthquakes, but if observation confirms the idea of their connection with a certain geological structure of country, we shall at least be able to point out where danger is to be peculiarly apprehended, and by avoiding such localities, dirninish the fearful records of death and suffering, by which the occurrence of Earthquakes has hitherto been accompanied.
It will afford the writer the highest satisfaction to be furnished with detailed accounts of Earthquake shocks, in whatever part of India they may occur; and in any cases in which the expence of Postage may be a consideration to observers, he begs they will have no hesitation in forwarding their remarks to him "bearing."* The subject is one of deep interest and importance, and the co-operation of observers in all parts of the country is earnestly solicited, since it is only by wide-spread observations that justice can be done to the subject, and such observations it is quite impossible for any single individual to collect satisfactorily. Sakaranpore, 5th April, 1842.
* Communications on the subject of Earthquakes may be addressed to the author at Saharunpore, Upper India, or if preferred, he has no doubt the pages of this Jouroil will be cheerfully opened to them.
Most unquestionably. Any number of copies of any such paper will be printed in4 stitched as a pamphlet for (gratis) distribution, and distributed as required, or sent to the author. -p
Notice of the predatory and sanguivorous habits of the Bats of the genus Megaierma, with some Remarks on the blood-sucking propensities of other Vespertilionidte. By Edward Blyth, Curator to the Asiatic Society.
Chancing, cne evening, to observe a rather large Bat enter an outtouse, from which there was no other egress than by the door-way, 1 vras fortunate in being able to procure a light, and thus to proceed to the capture of the animal. Upon finding itself pursued, it took three or four turns round the apartment, when down dropped what at the moment I supposed to be its young, and which I deposited in my handkerchief. After a somewhat tedious chase, I then secured the object of my pursuit, which proved to be a fine pregnant female of Megaderma lyra. I then looked to the other Bat which I had picked up, and to my considerable surprise, found it to be a small Vespertilio, nearly allied to the European V. pipistrellus, which is exceedingly abundant not only here, hot apparently throughout India, being the same, also, to all appearance, as a small species which my friend Dr. Cantor procured in Chuaa: the individual now referred to was feeble from loss of blood, which it was evident the Megaderma had been sucking from a large and still bleeding wound under and behind the ear; and the very obviously suctorial form of the mouth of the Vampyre was of itself sufficient to hint the strong probability of such being the case. During the very short time that elapsed before I entered the out-house, it did not appear that the depredator had once alighted; but I am satisfied that it sucked the vital current from its victim as it flew, having probably seized it on the wing, and that it was seeking a quiet nook where it might devour the body at leisure. I kept both animals wrapped separately in my handkerchief till the next morning, when procuring a convenient cage, I "T5t put in the Megaderma, and after observing it some time, I placed the
other Bat with it. No sooner was the latter perceived, than the other fastened on it with the ferocity of a Tiger, again seizing it behind the ear, and made several efforts to fly off with it, but finding that it must needs stay within the precincts of the cage, it soon hung by the hind-legs to one side of its prison, and after sucking its victim till no more blood was left, commenced devouring it, and soon left nothing but the head and some portions of the limbs. The voiding? observed very shortly afterwards in its cage resembled clotted blood, which will explain the statement of Steedman and others concerning masses of congealed blood being always observed near a patient who has been attacked by a South American Vampyre.
Such, then, is the mode of subsistence of the Megaderms. The sanguivorous propensities of certain Bats inhabiting South America have long been notorious, but the fact has not heretofore been observed of any in the old world*; and the circumstance of one kind of Bat preying upon another is altogether new, though I think it not improbable that the same will be found to obtain (to a greater or less extent) among the larger species, if not throughout the whole extensive allied genus ui Rhinolophus, (or the horse-shoe Bats,) which, like Mcgaderma, are peculiar to the Eastern world.
It may appear strange, that with the multitudinous attestations ascribing blood-sucking habits to certain Bats of South America, naturalists have been found unwilling to credit the statement, as instanced by Mr. W. S. McLeay, who, in a note appended to the remark that >
• There are, it is true, certain vague statements, but quite unworthy of creJit, ascribing sanguivorous habits to the Pteropodes. Thus De Vaux, in his ' Letirn from the Mauritius,' (p. 65), describes these animals to "feed indiscriminately <* fruit, small warm-blooded animals, and insects, as well as to suck the blood of n>f and cattle." But were this the case, the fact would assuredly be well known in Indii. where "Flying Foxes," as they are termed, are so very abundant. Of onebroagk alive into France, it is indeed stated, that "during the voyage, on one occasion «rhra its food ran short, it fastened upon a dead fowl, and made a meal of part of it; Iei from that time animal food was occasionally given to it:" but I doubt much wbetkn this was a natural appetite of the creature, from observation of one exhibited in England by Mr. Cross, of the Surrey Zoological Hardens, and puffed by him in advertisements and hand-bills a? the wondrous " Vampyre." This animal would eat nothingb»' fruit and vegetables, and constantly refused insects, a variety of which 1 offered l''1 It was tame, and appeared fond of being noticed. Hence I am also inclined to do"* ■a statement which I have somewhere met with, to the effect that the little Kiodotf o partly insectivorous, this animal being known with certainty to feed largely Ob UV fruit of the Eugenia.
particular species of butterfly, inhabiting Cuba, is much preyed upon towards the evening by different species of Bats, adds " principally the Pkillostoma Jamaicense [Arctibeus Jamaicensis, Leach]. By the way," remarks this observer, "in the 2d edition of the Regne Animal, the author says of the Phillostomes, 'Ce sont des animaux d'Amerique, qui ont l'habitude de sucer le sang des animaux;' I can only say that this is not only quite untrue as respects the Cuban species, but perfectly impossible [!]. The Ph. Jamaicense, for instance, lives on fruits and singed insects, in search of which latter it will be found in bed rooms. The Vampyre Bat of South America is also a Phyllostoma of Cuvier and Geoffrey; but until some person having pretension to the name of naturalist shall establish the fact on personal observation, I shall as readily believe that it sucks the blood of men as that the Caprimulgus sucks the milk of goats."—Trans. Zool. Soc, I, 187.
This is rather a sweeping denunciation of the detailed assertions of Condamine, Steedman, and a host of others, though there is now every reason to conclude that Mr. McLeay is perfectly correct, so far at least as regards the Phyllostomata attacking large animals; and concerning this genus, too, he mentions a fact which is not generally known, stating that its members are partly frugivorous. The same is, however, alao noticed by Mr. Swainson, who informs us, (Class. Quadrupeds, p.. 94,) that "several of the Brazilian Bats are likewise frugivorous, and to such a degree, that we remember never having been able to secure a ripe fig from a garden we possessed at Pernambuco, and where many of these trees grew : nets, indeed, were spread over them, but the cunning animals seemed to have the instinct of mice; they crept under the smallest opening, and completely baffled our endeavours to stop their plunderings." But this author also notices the sanguivorous habits of at least some South American species, mentioning that, " Our horses and mules, after having arrived at the end of a day's journey, and been turned out to graze, would be brought in by the guides in the morning with their shoulders covered with blood."
To be brief, in all instances wherein the habits of the Phillostomata have been directly observed, the result has corresponded with the above statements. Mr. Waterton, for example, tells us, in his celebrated 'Wanderings,' "As there was a free entrance and exit to the Vampyre in the loft where I slept, I had many a fine opportunity of paying attention to this nocturnal surgeon. He does not always live on blood. When the moon shone bright, and the fruit of the banana was ripe, I could see him approach and eat it. He would also bring into the loft, from the forest, a green round fruit, something like the wild guava, and about the size of a nutmeg. There was something, also, in the blossom of the suwarre nut tree, which was grateful to him; for on coming up a creek, on a moonlight night, I saw several Vampyres fluttering round the top of the suwarre trees, and every now and then the blossoms, which they had broken off, fell into the water. They certainly did not drop off naturally, for on examining several of them, they appeared quite fresh and blooming. So I concluded the Vampyres picked them from the tree, either to get at the incipient fruit, or to catch the insects which often take up their abode in flowers.
"There are," according to Mr. Waterton, "two species of Vampyre in Guiana, a larger and a smaller. The larger sucks men and other [mammiferous] animals; while the smaller seems to confine itself «hiefly to birds. I learned from a gentleman, high up the river Demarara, that he was completely unsuccessful with his fowls, on account of the small Vampyre. He shewed me some that had been sucked the night before, and they were scarcely able to walk." He then proceeds to give a humorous account of his companion, a North Briton, who had been bitten by one of these creatures, and lay muttering imprecations on the whole race of them. "As soon as there was light enough," writes Mr. Waterton, "I went to his hammock, and saw it much stained with blood. 'There,' said he, thrusting his foot out of the hammock, 'see how these infernal imps have been drawing my life's blood.' On examining his foot, I found that the Vampyre had tapped his great toe : there was a wound somewhat less than that made by a leech; the blood was still oozing from it. I conjectured he might have lost from 10 to 12 oz. of blood.
"I had often wished," continues this observer, " to have been once stung by the Vampyre, in order that I might have it in my power to say it had really happened to me. There can be no pain in the operation, for the patient is always asleep when the Vampyre is sucking him, and as for the loss of a few ounces of blood, that would be a trifle in the long run. Many a night have I slept with my foot out of the hammock, to tempt this winged surgeon, expecting that he