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much sensibility as water itself. It will be observed in the results above given, that (1) the motion was unaccelerated; (2) it increased with the inclination, and (when the inclination was not greater than 9 or 10°) in nearly the same ratio; and (3) the rate of movement was of the same order of magnitude as in actual glacial motion, which may be stated generally, in cases yet observed, never to exceed two feet a day.
by annual variations of the external temperature, and where consequently it was necessarily constant, how, it might be asked, were the internal pores and minute crevices of the ice to be again formed, when the infiltrated and subsequently frozen water had once filled these up, as it must necessarily do before it could produce a dilatation of the mass? No adequate solution had ever been given of these difficulties, and the author could not but consider this theory as being contrary to the most obvious mechanical and The extremely small friction between the physical principles; but while he expressed this plane and the ice indicated by the small inclinaopinion of the theory, he would also express his tion necessary to produce motion, was manifestsense of the important service which its distin- ly due to the circumstance of the lower surface guished advocate, M. Agassiz, had rendered to of the ice being in a state of gradual disintegrageology by the penetration with which he had tion, which, however, was extremely slow, as detected the effects of glacial action, and the proved by the small quantity of water proceedsteadiness with which he had maintained his ing from it. In the application, therefore, of general views on the subject. Another theory these results to the case of actual glaciers, it had also been put forward, which attributed the was necessary to show that the temperature of motion of glaciers to the expansion of water in their lower surfaces could not generally be less the act of freezing after it had filled, not the | than 32° Fah. Such, the author stated, must minute pores of the ice, but internal cavities of necessarily be the case unless the conductive considerable dimensions. But, since the tem- power of ice was greater than it was deemed perature of the glacier at considerable depths possible that it could be. For the proof of this, must be sensibly constant, how were new cavi- and for other details, he referred to his memoir ties to be formed when existing ones were thus on the subject recently read before the Camfilled up, if the cause now assigned were the bridge Philosophical Society. He also considerprincipal cause of glacial motion? The authored the subglacial currents as powerful agents in always regarded both this theory and the preceding one as totally untenable; and was thus led to examine how far the apparent objections to De Saussure's theory were really valid by a series of experiments on the descent of ice down inclined planes. The experiments were made in the following manner:-a slab of sandstone, pre-ed. pared to be laid down as a part of a common Hagstone pavement, was so arranged as to be easily placed at any proposed inclination to the horizon. The surface of the slab, so far from being polished, retained the grooved marks of the instrument with which the quarryman had shaped it. A quantity of ice was placed on the slab, and within a frame nearly a foot square, without top or bottom, and merely intended to keep the ice together without touching the slab, with which the ice alone was in contact. The following were results obtained in one set of experiments, the ice being loaded with a weight of about 150 lbs.:
the disintegration of the lower surfaces of glaciers, especially near their lower extremities.
Soon after the reading of the memoir above referred to, a work had appeared on the glaciers of the Alps by Prof. Forbes, the descriptive details of which could not be too highly commend
The results of his observations on the motion of the Mer de Glac of Mont Blanc afforded, as regarded that glacier, (and by inference as regards all other glaciers,) a complete refutation of the theories which attribute glacial movements to any expansion or dilatation of the ice. In this work, Mr. H. stated, the professor had put forth a new theory, which agreed with that offered by himself in attributing glacial motion to the action of gravity, but differed from it entirely as a mechanical theory in other respects. The author appeared to reject the sliding theory of De Saussure on account of the difficulties already mentioned, (which were now removed by the above experiments,) and assigned to the mass of a glacier the property of plasticity or
Spaces in decimals of an inch through Mean space semifluidity in a degree sufficient to account for
uon of which the loaded ice descended in sucplane. cessive intervals of ten minutes.
08 05 07 03 04 05 07 06 04
09 10 09 07 08
14 12 17 14 .19 .20
·38 34 36 27
The mass descended with an
the fact of its descending down surfaces of such small inclination. Thus, according to this theory, the motion was due to the small cohesion of one particle of glacial ice to another; while, according to the views now offered, the motion was due to the small cohesion of the lower surface to the bed of the glacier: the smallness of the latter cohesion had been proved by the experimental results above stated, that of the former appeared opposed to all observation, and was wanting When the weight was increased, the rate of in all experimental verification. Mr. H. stated motion was also increased: the least inclination his conviction that the internal cohesion of the at which sensible motion would take place was mass was immensely greater than its cohesion not determined, but it was ascertained that it to the surface on which it rests whenever the could not exceed half a degree in the case of a lower surface is in a state of disintegration. It smooth but unpolished surface. With a polished was perfectly consistent with this conclusion to surface of a marble slab, the motion of the ice in-assign to the glacier whatever degree of plasdicated a deviation from horizontality with asticity might be necessary to account for the reVOL. III. No. III. 27
lative motions of its central and longitudinal portions, under the enormous pressures to which, according to his theory, he showed it might be subjected. Such relative motions, however, were probably facilitated more by the dislocation than the plasticity of the mass. For a complete mechanical exposition of his views, he must again refer to the memoir already cited. Sufficient, he trusted, had been advanced to prove that the sliding theory assigned a cause adequate to the production of all the observed phenomena of glacial movements.
scattered over the plains, seems almost to confirm beyond further question the truth of the inferences drawn from these data. Col. Sabine also read a letter, stating that in the mountains to the N. W. of Bantry numerous traces of former glacier-action were to be seen.
Mr. Peach then read the following report:The object of this paper is to lay before you information which, connected with the other discoveries made of the fossil organic remains of Cornwall, may give to the rocks a "name and habitation" in the geological scale, which for With respect to the transport of erratic blocks some time past they have not had, without both and detritus of the Alps to the Jura, Mr. Hop-being disputed. I do not place my hopes so high kins observed that the greatest height which as to say that I shall do either positively; at any glaciers had formely attained in the valley of the rate, I believe there is now strong presumptive, Rhone (whence a large portion of the erratics if not positive, evidence, which will induce you had been derived) appeared to be well defined to come to a better finding than has been done by lateral moraines and polished rocks, while by the late trials on the subject. Hoping this, I the greatest height at which these blocks had have come over for the purpose of hearing the debeen deposited on the Jura was also well defin- cision, and being at the christening. In Messrs. ed. Thus, according to M. Charpentier, the Murchison and Sedgwick's paper, in the GeoRhone glacier must have risen at the mouth of logical Transactions, vol. v., new series, I find, the valley to about 2500 feet above the existing when speaking of the rocks of Polperro, they surface of the Lake of Geneva, while the high-say, "As the same prevailing northern dip is est band of detritus on the Jura was stated to continued to the mouth of the Fowey river, it is rise to a still higher level. It was inconceivable, obvious that the beds above described are infetherefore, that such detritus should have been rior to the fossiliferous group." Some time ago lodged at its present elevation by former gla-I received from the Messrs. Couch, surgeons of ciers. The only way in which it appeared pos- Polperro, in a letter, two or three pieces of what sible to obviate the mechanical difficulties of the they considered coral from the rocks of their subject was, to suppose the transport to have neighborhood. I thought them interesting, but been effected when the Jura was at a lower could not agree with them that they were coral, level relatively to the Alps, and the whole dis-and gave my opinion that they were portions of trict lower relatively to the surface of the ocean. In such case, the space between the Alps and the Jura may have been occupied by the sea, and the ice, with its transported materials, may have passed from the former to the latter chain, partly with the character of a glacier, and part ly with that of an iceberg. This hypothesis is perfectly consistent with the supposition of the general configuration of the surface of the Jura having been the same at the epoch of transport as at the present time; and Mr. H. believed it would be found equally so with all the observed phenomena of that region.
bone, and probably fish-bone. These gentlemen were both opposed to me, and said, "that they knew of no bone with such a structure." This added strength to my suspicions, from having somewhere gleaned, "that the structure of the fossil fishes of the older rocks agreed with that of no known existing ones." I felt determined, if possible, to examine these rocks. On the 20th of June last I did so, accompanied by Mr. R. Q. Couch, when, to my inexpressible delight, I found a large and extensive fish-bone bed, extending east and west of Polperro, containing immense quantities of portions of the cephalasCol. Sabine read a letter from an officer of the pis and onchus of the old red sandstone, with a antarctic expedition, stating that in the lat. 79° few other indistinct and ill-defined shells; also they had met immense cliffs of ice, forming the portions of the skin or shagreen of the sphagodes, sea-borders of an enormous glacier, above which, &c. of the upper Ludlow rock, all figured and at a great many miles distance, the tops of the described in Mr. Murchison's silurian remains. mountains were visible. The ice-cliff was con- These remains are found in the rocks described stantly breaking and tumbling down, and the in their paper, quoted above, with the "transdisjoined masses congregated and floated away verse fracture," and placed by them as "inferior to the north to the 60th degree of lat., where an to the fossiliferous group." I must beg of you enormous extent of icebergs were constantly to to bear with me a very short time longer, just to be found floating and not fixed to any submarine say, that when I had the honor of reading my ridge. Here they were constantly depositing, paper before this section at Plymouth, I menby their dissolution, immense quantities of stones, tioned my having found "fish-bones," and also earth, and other materials brought from the dis-" remains of a fossil, the structure of which retant mountains of the antarctic region. The re-sembled sepiadæa ;" and although I could not markable analogy of this great extent of glaciers convince you then of such being the fact, from and iceberg action to the presumed processes the obscurity of the specimens then produced, I supposed to have taken place on the earth dur never could banish from my mind the fossil fish ing the distant cold period, of which the traces of Cornwall. Now I believe I may say without remain in the elevated ridge of boulders at a doubt, the specimens I produce give proof posiheight of 2500 feet above the present glaciers in tive that I then had truth on my side; and if I the Alps, with the marks of scratching and po- feel highly delighted with the discovery, I trust lishing on the Alpine tops, and the erratic blocks | I shall be pardoned. I will just mention that I
have found similar remains, though small and indistinct, from the Gribbon to beyond Fowey, and from Looe to two miles eastward of that place: they agree with those of Polperro, and at Fowey are in a similar rock with the "transverse fracture." I pretend not to advance any opinion on this discovery, but leave the matter in your hands, merely mentioning that the proof is furnished for those who argued so much against the proper position of the Cornish rocks "from the absence of fish remains;" that obstacle is now removed, and full proof supplied; and I trust that some one well able will soon take the matter up and do us that justice we require. As I am now on my legs, I will just mention that I have found a conglomerate near Caerhayes Goran, in which are large rounded limestones, enclosing corals, cruisidea, orthercerites, &c. These are mingled with green-stones, argillaceous schist, porphyry, &c.
Mr. Murchison said that he felt much pleasure to be able to state that he could bear testimony to the truth of the specimens produced by the author of the paper being fish remains, and that they were of exceeding beauty. One which he held in his hand bore the name of (he trusted he should be pardoned in mentioning it) Onchus Murchisoni, and he could not distinguish it from the one figured in his silurian remains: several others also bore great resemblance to others figured and described in that work. There were some which appeared to differ, and which it would be necessary to submit to the inspection of Prof. Agassiz.
Prof. Phillips then said, that, through the kindness of the author, he had been permitted to read the paper and inspect the specimens then produced; that they were of exceeding beauty and of great value he hesitated not to say, and would greatly facilitate the settlement of the long-disputed question of the age of the rocks of Cornwall. He well remembered when at Plymouth doubting the statement then made by Mr. P. respecting some of the specimens produced, but now all doubts were completely removed from the very perfect state of the specimens; his only regret was that more were not produced. His opinion, if he must give it, was, that before any decided steps could be taken, a very careful examination of the specimens must be made, as amongst them he observed new forms. He felt perfect sympathy with the author in his great delight in the discovery, and complimented him on his perseverance in carrying out his suspicions.
Mr. Peach thanked the gentlemen for their kindness, and said that as he had to travel on horseback to get to the steamer, he could not conveniently carry larger specimens. He also said that it would give him great pleasure to render all the assistance in his power to any one who felt desirous of carrying on the researches, and that his collection might be used for that purpose; for he felt happy in stating that he had an extensive one of very good specimens. Prof. Owen read his report on British fossil mammalia, (to hear which a crowded auditory might be anticipated.)
The present division of his researches was addressed to the remains of mammalia which were
exclusively vegetable feeders, beginning with the order of Pachydermata of the largest size; respecting which he said he would, vivá voce, condense the pith of the paper, so as to bring it within the limits of the time which could be allowed for its discussion. He began with the genus Elephas, and noticed the early reports of its bones being discovered in countries where the animal was no longer to be found. These, together with the rhinoceros and hippopotamus, were referred to Pyrrhus and the Roman legions; insomuch that Cuvier's anatomical distinctions (about 1796) could not obtain much of public credence or attention. But the British specimens which had since been discovered fully confirmed all he had advanced; and Sir Hans Sloane's fossils were demonstrated not to be the ossemens fossiles of the elephant which Polinæus states to have accompanied the invading army of Cæsar. The rhinoceros and hippopotamus never could have been brought hither by the Roman armies; and the bones of the elephant were equally found in Ireland, where the Romans never were. Such remains were scattered over all the pleistocene strata of Europe; and those in the soil of Great Britain differed from both the living species of the El. Indicus and El. Africanus. He pointed out wherein this difference in the structure of the teeth (of which colored diagrams and sections were exhibited*) consisted, and showed that they must have been intended for crushing and comminuting coarse branches of trees. They bore, however, though distinct species, a greater resemblance to the Indian than to the African elephants. The skulls were also different; and he could say, from more than 3000 mammothteeth which he had examined from British strata, that the conclusions he had just stated were unquestionable. Here the professor pointed out a remarkable succession of molars, resembling the living elephant's-a constant growth to supply the place of those which were going out, the number of plates increasing in a regular geometrical ratio; and spoke of its correspondence with the general law of development, of all animal tissues from the primordial cells. Upon the whole, he was not inclined to agree with those authors who from a difference in the number of dental plates were of opinion that there were several distinct species of mammoth (Parkinson supposed two, one in Essex, and another in the Yorkshire Museum; Von Meyer admits eight); on the contrary, and the same was to be observed of the remains in the American drift, exhibiting the same varieties as the English,-the apparent difference depended entirely on the age of the animal, as the enamel-isles wore away, and blended into one transverse section. Neither was there any corresponding difference in the bones to warrant the inference that there was more than one species. There was also only one in Africa and one in India. Ours was identical with the Siberian. He then mentioned the measurement of parts of several skeletons in support of his position, and in demonstration of the gigantic size of the extinct elephant of the
*There appeared ridges and deep fissures of various forms, filled with enamel and transverse plates, which would work like millstones in crushing their food.
northern latitudes. The humerus, or upper bone of Wight the remains were mingled with comof the fore-leg, of a Norfolk mammoth measured minuted shells and marl, and also with fresh4 feet 5 inches in length; that of the large Indi-water reptiles. The modifications of the teeth an elephant, Chuny, killed at Exeter 'Change, and bones, by which these extinct pachyderms 2 feet 11 inches. Corresponding comparisons connected the tapir and rhinoceros with the were made with the femurs and other bones. ruminant order, were explained. The lophioThe parts of England in which such fossil re-don, from the eocene clay, near Maidstone, remains occurred were numerous. They were sembled a huge hornless rhinoceros; and the abundantly dredged up (2000 teeth, we believe) still more restricted locality in the Isle of Wight off the Norfolk coast; they were found in Suffolk, yielded more anomalous genera of pachyderms. in Essex, in the bed of the Thames, in the gra- There was the jaw of a chæropotamus, 6 or 7 vel of the metropolis,* in the valley of the Med-inches in length, forming a transition between way, in the vicinity of Brighton, (where Dr. the hog and the bear, and having a more carMantell had made so valuable a collection,) in nivorous character in the upper teeth. It was Wales, and on the Severn; on the Avon, where something like the piccary. From the freshthey were mingled with fresh-water shells; in water formations of Seafield and Binsted there the coarse gravel of Scotland; in Cavan and were remarkable analogues. Prof. Owen now Tyrone, Ireland: and often crushed and broken referred to the cranium of a very remarkable by tremendous force. This he considered to be extinct small pachyderm, about the size of a effected by ice in motion. The bed of the Ger- hare's, discovered in the London clay, near man Ocean was also rich in similar organic re- Herne Bay, in 1839. From the structure of its mains; bones and teeth of the mammoth had teeth it was seen in this respect to resemble the been dredged up off the Dogger Bank and in chæropotamus, and he had given it the name of the British Channel.-The evidence of the next hyracotherium. It was the smallest example of genus examined related to the mastodon, an ani- the pachydermal order. Another species had mal also with a proboscis, of which there was been found in Suffolk, in the eocene sand, assonow no living representative. It was found in ciated with the remains of the fossil monkey dethe lower deposits, with fresh-water and marine scribed in the first part of the report.-The shells, forming Lyell's 'fluvio-marine crag,' in paper next passed to the fossil remains of the Norfolk and also at Whitlingham; the strata genus Sus, or hog. They were abundant in being less recent than that in which the elephant Auvergne, and also found in the miocene of was imbedded. It was identical with the re- Norfolk. There they were associated with a mains discovered in France and Germany, and Felis as large as a leopard, and with the mastoespecially in the miocene of Hesse Darmstadt; don. More recent remains of the hog had been and he considered it to be the same as Cuvier's found in a peat-bog, with immense quantities of M. angustidens; with which reasons were as- hazle-nuts. The next genus, Equus, was very signed for regarding the Mast. longirostris of Dr. common in different formations. Like the Coup as being identical. American horse, it was distinguished by a greater degree of curvature in the teeth. It had been found of two sizes: the one might be a zebra, the other was thirteen hands high. Of the ruminants he now came to the gigantic deer, improperly called the Irish elk, for it was not confined to Ireland, but was spread over England, the Isle of Man, and other sites, and was in reality not an elk at all. It was a fallowdeer, with a slight affinity to the reindeer. The females had no antlers, (which had led some erroneously to imagine there were two species,) and there was a slight resemblance to the skull of the giraffe, in a middle eminence, which had been compared to a third horn. It was found in the Isle of Man in fresh-water basins, in strata posterior to the pleistocene period. The enormous extent of the antlers of the male was proved by one pair being 9 feet 2 inches from tip to tip. A second species of fossil cervus could not be distinguished from the red deer, and was very generally dispersed. A third species was identical with, and only a little larger than, the fallow-deer. A specimen of roebuck was also noticed. Genera of Capra, or goats, were next treated of; they were found with mammoth, deer, &c. But the professor had not traced the sheep to this remote period by any well-marked fossil remains. The last animal brought forward was the Urus, or oxen, discovered in fossiliferous caverns, and far larger than any now in existence. They were found in Essex till and drift, and might pos
The learned professor next adverted to the former existence of the rhinoceros, almost entire skeletons of which had been found in England. Thus, it was taken from a cavernous fissure in a limestone-quarry near Plymouth, also at Wirksworth; together with large deer, the ox, and cave carnivora, including the gigantic felis. Other caves were filled to the top with similar remains, which had either been drifted into them, or accumulated from the fall of the animals. This rhinoceros corresponded mostly with the two-horned rhinoceros of Siberia, and differed from all existing species in the form of the skull. The diagrams, to which we have alluded, on the walls of the room enabled the professor to explain the structure of the fossil-teeth of the rhinoceros, and likewise of the hippopotamus, and show that they were quite differ: ent from those of the living species now confined to Africa. These remains of hippopotamus were discovered near Brentford, 40 feet below the level of the Thames, and elsewhere. They identified the creature with Cuvier's H. major of the continent.-The attention of the meeting was next directed in succession to vegetablefeeding Palæotherium and Anoplotherium, discovered in the older tertiary strata. In the Isle
As in Gray's Inn Lane, and in the county of Northampton, 6 feet delow the surface, and many other places. Dr. Buckland found them in great numbers, accompanied by the bones of the hippopotamus and byæna.
sibly be the Auzochs still living in some parts Menzikoff, a Russian exile, who died in banishof Russia. Essex was rich in these and other ment, and was buried in full uniform, with all remains. An extinct species of short-horned his orders upon him, in the frozen soil of Siox was preserved in the late John Hunter's beria. A hundred years after, his grave was museum; and the same species had been dis-opened, and the corpse was found as fresh as covered by Mr. Ball in bogs in Ireland. This when interred, the clothes and orders all perfect, species had a longer and narrower forehead and the whiskers and moustachios as in life. than the modern favorite short-horned breed.
There were many other remains, from more superficial deposits, in the beds of rivers, and bogs. There were sheep, hogs, dogs, and cats. A gravel-pit in Lincolnshire, two miles from the sea-shore, afforded all these; but they could not be regarded as true fossil or extinct remains.
Such preservation might account for many geological phenomena. He concluded by warmly eulogizing Prof. Owen for his valuable report.
Zoology and Botany.-Prof. E. Forbes then proceeded to describe the sea needles of the order Nucleobranchiata, which he has added to the British Flora, and generally the genus SaAfter stating all the varieties, the professor gitta, a gelatinous animal with horizontal fins. took a comprehensive retrospect of the whole; He had first found the new order (of which two and his survey of extinct mammalia was listen- enlarged drawings were suspended on the wall) ed to with intense interest. The oldest re- while cruising in the Frith of Forth, and near mains were in the middle of the oolite series;| Guernsey, and laid it before the Wernerian Soand they were entirely different from any exist-ciety, who coincided in his opinion that it was ing animal. They appeared to be allied to the anomalous, and might be the type of a genus, as Marsupialia of New South Wales. From hence he did not know what else to do with it. It dif to the tertiary there were no remains, till we fered from the Medusa in being symmetrical. came to the eocene clay. Here the very strange The only circulation he had been able to detect. forms of Palæotheria, Charopotami, Anoplothe- was in certain globules in the tail. He had ria, Hyracotheria, &c. presented themselves, seen no more of them till he visited the coast of taxing to the utmost the skill of the comparative Greece, where he met with them in vast numanatomist; next came the miocene, with the bers. There they were much larger than in our mastodon, &c.; then the pliocene and post-plio- seas, and very active in their habits, darting cene, and unstratified drifts, in which were buried about the glass in which they were placed, and countless mammoths, with bears, hyænas, &c.; erecting a bristly process or fringe about their and so the ladder approached to the animal life head, as might be seen in the drawings he had of the present time. In conclusion, Mr. Owen made of them. They were about two inches alluded to the facilities afforded to future in- long. Dr. Allman stated that he had discovered vestigators and collectors of fossils by the classi- Sagitta on the coast of Ireland; and Mr. Patterfied summaries given in the reports called for son inquired about some cavities in its head, by the British Association, and expressed his which he thought might afford means of identiacknowledgments for the aid and encourage-fying it with the genus Cydippe. Professor ment afforded by the Association in the prose
cution of these researches.
Forbes pointed to a difference: the Cydippe possessed the power of attaching itself to any body, which the Sagitta had not.
Mr. R. Dowden read a paper on the phosphore-rescence of plants. In this he mentioned that his attention was attracted to the luminous rays proceeding from a bed of marigolds; the light was vivid and scintillating, of a light golden tinge, and the weather was particularly warm and dry. On turning his back to the light, the luminous appearance became more vivid; to test the source of the light he watered the flowers, which, not diminishing the effect, dispelled the idea of its being electrical, and, on considering the color, he could not allow it to proceed from any irritation of the retina, or the complemental color of the marigold, a light green, would have been produced. He thought the source of the light to be phosphorescence; the double marigold was the only one suited for examination, as the other closes with the sun. He said that the Indian cress when shaken emitted flashes; and thought that all orange flowers were phosphorescent.
Mr. Murchison called the attention of the section to the geological points illustrated by the report; and referred particularly to the mains in the eocene group, as he had but lately returned from the country. In the tertiary basin of Frankfort and Mayence, and the valley of the Rhine, a vast multitude of animals were congregated together; and in one place a remarkable new group had been brought to light. It was, he observed, difficult to resolve the ages of the tertiary deposits, and those who attempted to base a system upon shells might afterwards find themselves altogether in error. He mentioned the calicotherium, a link in the mammalian chain; also a saurian, or lizard, an inch or two long; a Pisodon Coleii of very remarkable structure. All the tapira, rhinoceroses, &c. were of the Sumatran type, and differed from those of Europe. The question arose with regard to the superficial deposits, were they all of local character, and the animals living upon the adjacent hills? This seemed to be the case from entire skeletons being found, and many others where the bones were slightly detached from each other. Or, had there been a cataclismal and general destruction, such as Pallas supposed the great Asiatic drift to have been? Or, would change of climate explain these phenomena? This last idea he illustrated by a curious story of Prince
Dr. Allman did not agree in the explanation given by Mr. Dowden, but attributed the appearance to a phenomenon mentioned by Sir D. Brewster, namely, that in obscure light, objects appeared, as it were, and disappeared intermittingly. This simple alternation, he thought, was sufficient to account for the curious effect.