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mind, however, will ponder and consider each feature of the case, and will rather prefer to countenance a supposition based on ordinary experience than an explanation brought ready-made from the domain of the miraculous. While not the least noteworthy feature of these cases is that included in the remark of Smellie respecting the tendency of uneducated and superstitious persons to magnify what is uncommon, and in his sage conclusion that, as a rule, such persons in the matter of their relations are not to be trusted.”

But it must also be noted that we possess valuable evidence of a positive and direct kind bearing on the duration of life in toads under adverse circumstances; and, as this evidence tells most powerfully against the supposition that the existence of those creatures can be indefinitely prolonged, it forms of itself a veritable court of appeal in the cases under discussion. The late Dr. Buckland, curious to learn the exact extent of the vitality of the toad, caused, in the year 1825, two large blocks of stone to be prepared. One of the blocks was taken from the oölite limestone, and in this first stone twelve cells were excavated. Each cell was one foot deep and five inches in diameter. The mouth of each cell was grooved so as to admit of two covers being placed over the aperture; the first or lower cover being of glass, and the upper one of slate. Both covers were so adapted that they could be firmly luted down with clay or putty; the object of this double protection being that the slate cover could be raised so as to inspect the contained object through the closed glass cover without admitting air. In the second or sandstone block a series of twelve cells was also excavated; these latter cells being, however, of smaller size than those of the limestone block, each cell being only six inches in depth by five inches in diameter. These cells were likewise fitted with double

covers.

On November 26, 1825, a live toad-kept for some time previously to insure its being healthy-was placed in each of the twenty-four cells. The largest specimen weiged 1,185 grains, and the smallest 115 grains. The stones and the immured toads were buried on the day mentioned, three feet deep, in Dr. Buckland's garden. There they lay until December 10, 1826, when they were disinterred and their tenants examined. All the toads in the smaller cells of the sandstone block were dead, and from the progress of decomposition it was inferred that they had succumbed long before the date of disinterment. The majority of the toads in the limestone block were alive, and, curiously enough, one or two had actualy increased in weight. Thus, No. 5, which at the commencement of its captivity had weiged 1,185 grains, had increased to 1,265 grains ; but the glass cover of No. 5's cell was found to be cracked. Insects and air must, therefore, have obtained admittance and have afforded nourishment to the imprisoned toad ; this supposition being rendered the more likely by the discovery that in one of the cells, the covers of which were also cracked and the ten

ant of which was dead, numerous insects were found. No. 9, weighing originally 988 grains, had increased during its incarceration to 1,116 grains ; but No. 1, which in the year 1825 had weighed 924 grains, was found in December, 1826, to have decreased to 698 grains ; and No. 11, originally weighing 936 grains, had likewise disagreed with the imprisonment, weighing only 652 grains when examined in 1826.

At the period when the blocks of stone were thus prepared, four toads were pinned up in holes five inches deep and three inches in diameter, cut in the stem of an apple-tree; the holes being firmly plugged with tightly fitting wooden plugs. These four toads were found to be dead when examined along with the others in 1826 ; and of four others inclosed in basins made of plaster-of-Paris, and which were also buried in Dr. Buckland's garden, two were found to be dead at the end of the year, their comrades being alive, but looking starved and meager. The toads which were found alive in the limestone block in December, 1826, were again immured and buried, but were found to be dead, without leaving a single survivor, at the end of the second year of their imprisonment.

These experiments may fairly be said to prove two points. They firstly show that even under circumstances of a favorable kind when compared with the condition popularly believed in-namely, that of being inclosed in a solid rock-the limit of the toad's life may be assumed to be within two years ; this period being no doubt capable of being extended when the animal possesses a slight advantage, exemplified by the admission of air and insect-food. And, secondly, we may argue that these experiments show that toads when rigorously treated, like other animals, become starved and meager, and by no means resemble the lively, well-fed animals reported as having emerged from an imprisonment extending, in popular estimation, through periods of inconceivable duration. These tales are, in short, as devoid of actual foundation as are the modern beliefs in the venomous properties of the toad, or the ancient beliefs in the occult and mystic powers of various parts of its frame when used in incantations. Shakespeare, while attributing to the toad venomous qualities, has yet immortalized it in his famous simile, by crediting it with the possession of a “precious jewel.” But even in the latter case the animal gets but scant justice; for science strips it of its poetical reputation, and in this, as in other respects, shows it, despite fable and myth, to be an interesting but commonplace member of the animal series.- Gentleman's Jagazine.

THE ELECTRICAL POLYSCOPE. HE electrical polyscope is a simple and ingenious apparatus for

a giving light in the cavities of the human body, the invention of M. Trouvé, who has distinguished himself bý the contrivance of several other instruments useful to physicians and involving curious applications of electricity. It consişts of an energetic and constant battery, of a reservoir or secondary battery, and of parabolic reflectors adapted to the different ,uses to which it may be applied, which are furnished with additional mirrors or used without them. A minute platinum thread, connected with the conducting wires of the battery, is placed in the middle of each reflector. When the battery is put in action, the wire becomes incandescent. A special rheostat is provided to regulate the flow of the electricity, which plays a part similar to that of the faucet of a water-reservoir, and controls the flow of the fluid with such exactness as to permit the finest threads of platinum

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to approach the point of fusion without passing it. The melting-point of the wires used having been determined in the beginning, can always afterward be avoided without trouble. A galvanometer with two circuits, in which the electro-motive force of the reservoir and that of the battery are in opposition, enables the operator to observe the condition of the apparatus at every moment. Figs. 1 and 3 represent two of the reflectors. That shown in Fig. 1 is used to light up the mouth, and is of such power as to render the teeth transparent, and make them show every detail of their condition. Placed on the extremity of a probe inserted in the esophagus, it makes it possible to observe the condition of the stomach. Fig. 3 shows the reflector with mirrors for use in laryngoscopy and rhinoscopy. This adaptation of the instrument may be used by dentists to show the back part of the teeth, without compelling the patient to assume a disagreeable position, as in Fig. 2. The polyscopes are superior to every other device for introducing light to all parts of the human body. With them the source of light may be placed at as minute a distance as is desired from the part to be examined without inconvenience to the operator. With a slight modification the polyscope may be employed as the instrument for performing the very different operation of cauterization. It is of service in other fields than those of medicine and surgery. Captain Manceron, at St. Thomas of Aquinas, has used it to examine the interior of shells and cannon. It is employed likewise in powder magazines, and is a similar apparatus to that used by divers and gatherers of oysters, corals, and pearls, to light up the bottom of the

sea.

CAPTURE AMONG THE MOLLUSKS.

MR

R.

ing a shanny and a mussel, which he describes as having been taken in the harbor at Looe, Cornwall, in exactly the position represented in the accompanying illustration. The shanny and mussel, our correspondent writes, were taken by a fisherman who was gathering mussels for bait at Looe. Mussels are found in great numbers at the bottom of the harbor there, and the fishermen use a long-handled, four-pronged fork for catching them. A boat is moored over the spot on which the mussels are to be found, and the fork is employed to bring them from below into the boat. In the case in question, our correspondent assures us the shanny and mussel were brought up as shown in our illustration. The fish was alive when taken, and its head firmly fixed in the mussel. This certainly may be considered a curious capture, and from the evidence it may be fairly assumed that the shanny, seeing a tempting mussel with its mouth open, was induced to pop his head in—an operation which Master Mussel doubtless resented by immediately closing its valves, retaining the fish in its dead

A case in point of fish being taken in this way is mentioned by Couch, in which Lacépède records an instance where, as he (Lacépède) supposes, a shanny had made an attempt to feed on an oyster

ly grasp.

that lay with its valves open, in consequence of which it became shut up a prisoner by the closing of the shell. In this case, however, the shanny was more fortunate than the one taken the other day, for it is stated that in this condition of confinement the fish had continued so long that the oyster had been dredged and carried to a considerable

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distance. Upon opening it, the captive was again set free alive, and without injury. Sbanny are very retentive of life, and would be found nice additions to salt-water aquaria.

In our columns some years ago was recorded an even more extraordinary capture than either of the above, by Mr. Frank Buckland. As doubtless many of our readers have not seen it, we reproduce Mr. Buckland's remarks and the illustration which appeared at the time :

“Some time since, when examining the famous oyster-beds at Helston, near Falmouth, Mr. Fred Hill, of Helston, was kind enough to accompany me and my friend Mr. Howard Fox, of Falmouth, in our expedition. Mr. Hill mentioned to me at the time that he had a curious specimen of a bird that had been caught by an oyster. The bird and oyster had been mounted in a case by Mr. Vingor, of Penzance. I have received from Mr. Hill a photograph of the above event, which I have since had engraved as above. The history is, that a woman who sells oysters went one morning to the Helford River and found the bird -a common rail-dead, with its beak held quite firmly by the oyster, which was still alive.

“The bird in all probability was wandering along the foreshore looking for bis dinner, and Mr. Oyster-possibly left longer by the tide than usual-was opening his shells waiting the incoming water. The hungry rail, seeing something that looked like a white and dainty bit of food, pecked at the body of the oyster, and probably pricked him sharply with his beak. The oyster then snapped his shells together as

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