mant and inactive lungs are gradually evolved, and come into play; and the four limbs are developed. The aquatic is now transformed into a terrestrial animal,-adapted essentially for a terrestrial existence for although the frog be an expert swimmer and diver, and is enabled, from the peculiarities of its respiratory function, to remain a considerable time beneath the water, still it must, of necessity, have frequent access to the atmospheric air; and would shortly perish, like any other terrestrial animal, if submerged in that fluid, the presence of which was essential to its existence in the tadpole, or larva, state. Here, then, we have not only an adaptation of peculiar organs to a peculiar state of existence; but a perfect and most striking change in the adaptation of the former to the altered circumstances in the mode of life. There is assuredly nothing in the transformations of Lepidopterous Insects, astounding as those transformations really are, nothing more wonderful, or unanswerably demonstrative of design and providence in the works of creation, than this. I envy not the constitution, the feelings, or prospects, of that mind, which can contemplate the metamorphosis of the aquatic and fish-like tadpole into the air-respiring and reptile Frog, without a deep conviction that these are wonders which an Omniscient Spirit could alone have projected, which an Almighty Hand could only have achieved. On these peculiarities in the structure and functions of the respiratory organs, the separation of the animals wherein they are exhibited, from the Reptiles, with which they have been until very lately confounded, principally rests. This peculiarity, however, the student will bear in mind, exists only in the early life,—or what may be called the larva state,—of our British Amphibia. Yet there are several exotic genera which, as the Proteus and the Siren, are permanently provided with both gills and lungs, and consequently capable of respiring, with equal facility and effect, in water and in air. These are, rigorously speaking, the only real Amphibia; as permanently and equally fitted for both an aquatic and terrestrial life.* The former, as possessing only temporary gills, are consequently arranged under the Sub-class, Caducibranchia; and the Proteus and Siren, as permanently provided with these breathing organs, under the Perennibranchia,t of modern Amphibiologists. + From compounds of the Latin Caducus, deciduous, and Perennis, permanent, with the substantive, Branchia, gills. The Newts, formerly arranged among the Lizards, which, in their exterior appearance, they so strikingly resemble, have, at length, been found to exhibit the same peculiarities in the economy of the respiratory process, as the various members of the Frog family: in early age, their respiration is branchial, or performed by gills; in the adult, pulmonary, or executed by lungs.** They have, consequently, been formed into a distinct genus, under the designation of Triton, and removed from the Saurian Order of the Reptile Class, to the Batrachian of the Amphibia. This presents a striking illustration of the influence of anatomical and physiological knowledge upon the progress and perfection of zoological arrangements. The Efts, or Newts, it should, however, be observed, do not, like the various species of Ranidæ, lose their tail, in the adult state. In the next number of The Analyst, I shall present a Systematic Arrangement of the British Fishes; with a few cursory remarks on the Anatomy, Economy, and Distribution of the Fish-Class. CORRESPONDENCE. P. SIR, TO THE EDITOR OF "THE ANALYST."+ I trust that a few cursory and general remarks made by me at Whitby, in Yorkshire, during the progress of the great solar eclipse on the 15th of May last, may not be uninteresting to your readers. Though I recorded the phases every ten minutes, I had not the requisite astronomical instruments to determine the data correctly, nor the means of comparison as to time. Numbers will no doubt supply ample and accurate data on these points. It seemed doubtful whether the eclipse would be observed annu * "The young are produced from eggs, laid on aquatic plants, breathe at first by gills, and have two claspers under the throat, by which they can adhere to a leaf. When the feet become perfect, the gills and claspers are absorbed."-Fleming, History of British Animals, vol. i., page 157. + This communication reached us at too late a period for insertion in our last number.-ED. lar at Whitby; but that beautiful phenomenon was certainly witnessed there, though the period, calculating from the formation to the dissolution of the annulus, did not exceed one minute thirty seconds it was accompanied by a tremulous or undulatory motion, and seemed as if the lines were interrupted, or appeared to break or dissolve into each other. On the evening previous to the eclipse, the atmosphere exhibited considerable dryness, for a saline efflorescence had covered the entire surface of the pier like hoar frost. Prior to the commencement of the phenomenon on the 15th May, I retreated from Whitby and took my station in a sequestered spot among the cliffs, that I might in solitude and silence contemplate, undisturbed, the glorious spectacle. In the shade at this spot at 1h. and 42′ p. m. the thermometer indicated a temperature of 68° F.; it then fell gradually at the rate nearly of two degrees for every ten minutes. At the period of the formation of the annulus, and of course of that of greatest obscuration, the temperature had fallen to 53° F. From this moment it gradually rose, and the thermometer at the close of the eclipse stood at 60° F. It is stated that during the period of greatest obscuration in the total eclipse of 1724, the thermometer had fallen only 2°. Short says, in reference to the eclipse of 1748, that they experienced no perceptible sensation of cold during its progress; but M. Cassini de Thury, who accompanied the King of France to Compeigne to observe this eclipse, states the reverse, though the thermometer fell only 2°. (Reamur?) In the present case, I not only became sensible of the increased cold, but the grassy carpet of the ground around me felt perceptibly damp. In fact, the hygrometry of the atmosphere was considerably changed. At 2h. and 50′ p. m. the flowers of the ficaria ranunculoides began to close, were soon afterwards followed by those of the daisy, and towards the termination of the eclipse all had sunk to rest, and the closure of their petals was complete; forming a beautiful illustration of the somnus of that great naturalist, the distinguished LINNEUS, as applied by him to the repose of plants. Several other flowers which enamelled the sod around me, were also more or less affected. A few flowers of the daisy and ficaria ranunculoides, which I had culled during the eclipse when their petals were closed, afterwards re-opened their flowers when put into water and exposed to the sunbeam. I may be permitted to remark that shortly after the impact and the umbra had made its appearance on the solar disc, I observed a faint light on the left of the apex of the umbra; it might be a de ceptio visus, but a somewhat similar appearance was witnessed by the celebrated MacLaurin in 1737, immediately before the completion of the annulus, towards the middle of the moon's circumference, not yet in contact with the disc of the sun. During the period of the eclipse, insect life was still and motionless; the birds of the air flew near the ground, and there was a peculiar solemnity in the silence which reigned around me-unbroken save by the song of the lark, which rose at intervals: even the "attic warbler" was mute, however, during the maximum obscuration. At the close of the eclipse numerous insects appeared, and the lark soared higher with its welcome note. The atmosphere had been almost free from clouds, but floating cumuli collected and condensed; and toward the close of the eclipse had rallied, as if in sympathy round the standard of the sun. The diminution of light was by no means so great as many had expected; no stars were visible-Venus, perhaps, might have been seen had not clouds at the time obscured her path. The light, during the greatest obscuration of the sun, was quite peculiar; nature assumed a lurid aspect, and the sea, too, had a different livery from its usual tone of colour. It was not a twilight hue,-it was "itself alone," such as I have seen in looking through a Claude Lorraine glass. The Prophet's language describes it-"The light was neither clear nor dark. It was not day nor night." During the solar eclipse of 1820, I was among the Serpentine rocks near Portsoy, Scotland, and the diminution of light on that occasion seemed greater than in the present instance. My distance from the tide-gauge did not enable me to consult it during the eclipse; but the usual height of the tide would have had its maximum on the 15th ultimo at 3h. 43': it did not, however, begin perceptibly to recede until four o'clock p. m., if it did not rather continue to flow so long. A death-like silence seemed to pervade the great deep, but about the maximum obscuration of the sun, I heard a wave below me 66 utter its voice," and " dash hoarse along the shore." 66 A friend informed me, while at Horncastle, that the tulips and anemonies in his garden there, shut their flowers during the eclipse, his bees ceased to work, the Thrush carolled his vespers or even song," and the poultry retired to roost. At Hull the maximum of temperature in sunshine was 86° F., and the maximum in shade 74° F. The minimum in sunshine during the eclipse was 64°5, and in the shade 64° F. At 3h. 27' p. m. the thermometer in sunshine was 1° 30' lower, there than in the shade: and a friend at Sheffield told me a similar phenomenon was observed in that town. I am inclin ed to think that this is entirely attributable to the difference of contraction in the base and stem of the instruments, from the variation in the rate of cooling; that in the sun being more rapid in its transition than the other. I remain, Sir, yours, &c. Hull, 22nd June, 1836. J. MURRAY. SIR, TO THE EDITOR OF "THE ANALYST." During a voyage across the Atlantic in the New York Packet Ship, Roscoe-Captain Delano—our conversation one day happened to turn on "the non-permeability of glass by water," when the Captain very obligingly allowed me to copy the following notes from his log-book; which notes I have great pleasure in forwarding to you, as they confirm the experiments made by Mr. Rudder, of which a description is given in the 13th number of The Analyst. An experiment to ascertain the pressure of the sea, off the Isle of France, 8th May, 1826, ship Florida : 1. A glass globe, bought for the purpose, was fastened to the leadline and sunk by three leads to the depth of 280 fathoms. 2. On the same line, 18 fathoms above the globe, I put a small bottle with an air-tight glass stopper. 3. Forty fathoms above this, a stout glass bottle, with a good cork sealed and covered with three coats of linen dipped in hot pitch. Each coat was allowed to cool before the other was put on. 4. Thirty fathoms above this, another bottle was attached to the line, much stouter and corked and sealed like the first, with only one covering of cloth. 5. Forty fathoms above this was a small bottle filled with fresh water, well corked. 6. Thirty fathoms from this an empty bottle, corked tight and sealed, a sail-needle passed through the cork and projecting on both sides. On hauling up the line The empty bottle (No. 6) with the sail-needle was half full of water, and the cork and sealing as perfect as ever. The cork of the second (No. 5) was loose and raised a little, and the fresh water a little brackish. |