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from Ponty-pool, in Monmouthshire; but it does not appear that any one has ascertained, or even suspected, the real nature of this singular product."

III. On the Difference of Structure between the Human Membrana Tympani and that of the Elephant. By Sir Everard Home, Bart. VPRS.-(See Annals, v. 69.)

The full sound of the French horn, we find, produced the same effect upon the elephant at Exeter 'Change, with the low notes of the piano-forte, as described in our report of this communication.

We have already explained the difference of structure between the human membrana tympani and that of the elephant, as here described by Sir E. Home: his observations on that membrane in other quadrupeds are as follows; they are illustrated, together with the immediate subjects of the paper, by engravings from drawings by Mr. Clift.

"The nearest approach I have met with among quadrupeds to this peculiarity in the elephant, is in neat cattle: in them the membrane is more oval proportionably than in the elephant; it is of an inch long, broad. The handle of the malleus lies in the direction of the transverse diameter of the oval, and extends two-thirds of its length; it is not, however, situated in the middle line of the oval, but so much nearer to the anterior side, that the fibres on that side are two-thirds shorter than those on the opposite.

"In the deer, the membrane is of an oval form, whose transverse diameter is of an inch, the conjugate: the malleus has its handle nearer the middle line than in neat cattle, the anterior fibres are of an inch, the posterior of an

inch long.

"In the horse, and hare, the handle of the malleus lies in the middle line, so that the fibres on the two sides are equal. In the hare the handle is more curved.

"In the cat, the fibres are nearly the same as in the horse. I mention this circumstance, since it leads to the conclusion, that the whole of the feline kind have a similarly constructed

organ.

The effect of the high notes of the piano-forte upon the great lion in Exeter 'Change, only called his attention, which was very great. He remained silent and motionless; but no sooner were the flat notes sounded, than he sprung up, endeavoured to break loose, lashed his tail, and appeared to be enraged and furious, so much so as to alarm the female spectators. This was accompanied with the deepest yells, which ceased with the music."

IV. Corrections applied to the Great Meridional Arc, extending from latitude 8° 9′ 38′′, 39, to latitude 18° 3′ 23′′, 64, to reduce it to the Parliamentary Standard. By Lieut. Col. W. Lambton, FRS., &c.

This short paper, it is probable, forms the last communica

tion respecting the measurement of an arc of the meridian in India, ever prepared for the scientific world by its lamented author; his decease took place, as we are informed by the Indian papers, on the 20th of January last, only eleven days after the present communication had been read before the Royal Society. We shall, on this account, be more particular in our analysis of these "Corrections," than, under circumstances of less interest, we probably should have been.

Col. Lambton first expresses his satisfaction at the results of Capt. Kater's experiments in examining and comparing the dif ferent standard scales; and his pleasure on finding "that the Commissioners for considering the subject of weights and measures have adopted Mr. Bird's scale of 1760, as by that means there is now a universal standard of comparison, which applies to the French metre, and to all the measures used on the Con tinent." "From Capt. Kater's results it appears," the Col. continues "that with respect to a measurement on the meridian, the degree depending on my brass scale must be multiplied by ,000018, and the product subtracted from the measure given by the scale, to reduce it to what it would have been, had it been measured by what is now the Parliamentary standard; and the degree depending on Ramsden's bar, by ,00007, and the product added to the measure given by the bar, to reduce it to the standard measure."

The arc which Col. Lambton measured, he next shows, depends on both these standards; and he then gives in succession its different sections, correcting them by the above factors as he proceeds. From these corrections we have the degrees as follows:

"The degree for latitude 9° 34' 44" for latitude 13 2 55

Fathoms.

60477-09 60490.31 42 = 60511.65

Indian.

46 = 60779.00 French.

60824-26 English.

for latitude 16 34
for latitude 47 30
for latitude 52 2
for latitude 66 20 12 60955.00 Swedish.

20

=

"Then computing from Eq. 3, page 498, in the Phil. Trans. for 1818, Part II., we shall have the ellipticity of the earth as follows: by the

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It is next shown, by means of a table computed from certain data given in the paper, "that the first degree in latitude 9° 34′ 44′′ by the measurement is 0.67 fathoms in defect; and that the degree in latitude 16° 34' 42" (which may be taken for 16° 34′ 44′′) by the measurement is 3.21 fathoms in excess." New Series, VOL. VI.

With respect to the dimensions of the earth, and the length of the quadrantal arc of the elliptic meridian, the author then deduces, that 60850·17 fathoms is the measure of the degree on the equatorial circle; and that "5467756 fathoms is the length of the quadrantal arc, which, reduced to inches, and multiplied [divided] by 10,000000, we get 39-3677 inches for the metre at the temperature of 62°, which falls short of the French metre by 0032 inches, when reduced to the same temperature."

"This conclusion is very satisfactory, and I hope that equal success will attend my operations to the northward. I have already measured another section, which extends to latitude 21° 6', having just returned from finishing it; and when all the necessary calculations and corrections are made, I shall draw out an account of the whole, and forward it to the Royal Society at a future period. The celestial arc has been determined by seven stars, but there are many now out of my reach which I observed in the beginning.

"It may be satisfactory to the mathematicians in Europe to know, that I am now advancing through Hindoostan; and from what I can learn from the different public authorities, I do not apprehend any difficulty. They are all inviting in their letters, and all seem desirous that I should go through their respective districts. If my present arc be continued direct, it will pass through Bopaul, and near Seronje, where I shall have again to observe the stars, and measure a base; and if Scindiah's country be in a quiet state, my meridian will pass through Gualior, his capital; and my sixth section will terminate near Agra, on the Jumna. I have made up my mind to execute all this if I live, and continue to have that flow of health and spirits which have hitherto attended me. The result of such an extensive measurement must be interesting to scientific men; and I shall exert my endeavours in doing justice to the work, and in giving a faithful account of the operations."

In concluding our notice of this paper, we cannot but express onr earnest hope that some fully qualified person may speedily be appointed to continue Col. Lambton's operations, as well in the measurement of the arc, as in the extension from it of a general survey of the country; the latter undertaking we believe, had already been commenced by Col. Lambton, and the present state of our knowledge respecting the geography of Hindostan imperiously requires its prosecution.

V. On the Changes which have taken Place in the Declination of some of the principal fixed Stars ;

VI. Appendix to the preceding Paper on the Changes which appear to have taken place in the Declination of some of the fixed Stars; and

VII. On the Parallax of a Lyra. By John Pond, Esq. Astronomer Royal, FRS.

To give a satisfactory account of these important papers

would occupy a far greater space than we could at present devote to the subject: we must, therefore, confine our extracts, in this place, to the conclusion of the paper on the parallax of a Lyræ; the difference between which and that of y Draconis, Mr. Pond finds, is absolutely a quantity too small to be measured, or it is zero; and his observations indicate, in the most decided manner, that the actual parallax of the former star cannot exceed a very small fraction of a second.

"Notwithstanding the importance of these investigations to the history of astronomy, and to our forming a correct notion of the system of the universe, yet our decision ultimately turns upon so very small a quantity, that our having reduced the inquiry to these narrow limits, rather tends to show the perfection of each instrument [of Greenwich, and of Dublin], than the defect of either."

"On former occasions, I considered the question of parallax in the particular case of a Lyræ as undecided, and as perfectly open to future investigation; but the observations of the present year have produced, on my mind, a conviction approaching to moral certainty. The history of annual parallax appears to me to be this: in proportion as instruments have been imperfect in their construction, they have misled observers into the belief of the existence of sensible parallax. This has happened in Italy to astronomers of the very first reputation. The Dublin instrument is superior to any of a similar construction on the Continent; and, accordingly, it shows a much less parallax than the Italian astronomers imagined they had detected. Conceiving that I have established, beyond a doubt, that the Greenwich instrument approaches still nearer to perfection, I can come to no other conclusion than that this is the reason why it discovers no parallax at all."

VIII. Observations on the Heights of Places in the Trigonometrical Survey of Great Britain, and upon the Latitude of Arbury Hill. By B. Bevan, Esq.: Communicated by Sir H. Davy, Bart. PRS.

By means of levelling to the canals, &c. Mr. Bevan found the country to the north of Arbury Hill suddenly to fall about 400 feet, and continue at this depressed state for nine or ten miles. This "defect of matter," he observes, "was a strong ground for supposing a deflection of the plumb-line to the southward;" and by calculating the latitude of Arbury station, from the latitude of Blenheim, as determined by previous observation, independent of any astronomical observation made at Arbury, he found it to be 52° 13′ 23′′, or five seconds less than was shown by the zenith sector. For the calculation by which this discrepancy was deduced, and for the other subjects of the paper, we must refer the reader to the original.

(To be continued.)

B.

ARTICLE XIV.

Proceedings of Philosophical Societies.

GEOLOGICAL SOCIETY.

June 20.-A paper was read, containing a Description of a Section of the Crag Strata at Bramerton, near Norwich. _By Richard Taylor, Esq.: communicated by John Taylor, Esq. Treas. GS.

This paper was accompanied by a sketch of the crag beds at Bramerton, resting upon the upper chalk, and a table was subjoined containing the respective thicknesses of the series of beds, with a list of such organic substances as belong to each.

A paper was also read, on the Geology of Rio de Janeiro. By Alexander Caldcleugh, Esq. MGS.

The mountains in the neighbourhood of Rio de Janeiro are for the most part composed of gneiss intersected by granite veins.

A siliceous stalactite was observed by the author to form in this district from the overhanging masses of gneiss, specimens of which were presented to the Society.

As the absence of hot springs makes the occurrence of these stalactites of very considerable interest, Mr. Caldcleugh offers the following hypothesis to explain their formation; the water which in Brazil constantly trickles down the bare sides of the hills, often reaches a temperature as high as 140° or 150° of Fahr. This warm water descending on decomposing strata of gneiss, such as is the case with that from which these specimens are taken, seizes the potash of the felspar, and then acts upon the quartz, and forms a siliceous stalactite. Some of the hot springs or geysers of Iceland do not reach the boiling point, and perhaps the quantity of silex dissolved, the inverse of what is shown to be the case with carbonate of lime, may, in a great measure, depend on the temperature of the alkaline solvent.

June 27.-A paper was read, entitled, "Observations on the Quartz Rock Mountains of the West of Scotland and North of Ireland, more particularly those of Jura, with an Account of the ancient Beaches and Trap Dykes of that Island, accompanied by a Plan and Sections."

The quartz rock is traced in a succession of districts from Lerwick, in Shetland, to the county of Donegal, in Ireland ; and in Jura the thickness of the mass is estimated at 10,260 feet. The similarity and singularity of form assumed by quartz rock mountains in districts remote from each other is deduced from the peculiar construction and material of the mountain mass acted upon by powerful aqueous currents. Quartz rock is of great extent in the county of Donegal, where, in one instance,

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