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arranged, they conspire to establish a virtual second joint, At the end of the second to-and-fro vibration the pen at right angles to the topmost joint, and at some point returns to the point whence it started, except that friction below it not necessarily coinciding with the position of compels it to fall short little by little at every stroke ; but any one of the actual joints, and apparently varying for if the adjustment is accurate, as it was in this particular different positions of the plane of vibration.

case, the shape of the curve remains the same from first At this stage I showed some of my pendulum's tracery to last, and the figure is filled up to the very centre by the to my brother-in-law, Mr. E. J. Routh, M.A., of St. orderly description of curve within curve conspiring to Peter's College, Cambridge, and received some hints from produce a web of lines of astonishing regularity. If the him which led me to adopt an arrangement whereby the adjustment of the connecting link is very slightly inaccuposition of the lower joint could be varied, so as to bring rate, the curve begins to change its shape little by little at the two periods of vibration into any simple proportion, every stroke, in one way or another, according as the link as 1 : 2, 2:3, &c. This was done by a very simple mode is too high or too low; and wonderfully intricate is the of suspension,-two cords hanging from two fixed points result, for after a due series of intermediate stages, the some distance apart, and passing through a small ring original figure reappears, but reversed; and aster anol er that could slide up and down the concurrent cords and be series of changes it presents its-lf again to view in its fixed at any height. In this arrangement I found the original posture, but much diminished by the friction that his germs of an infinite variety of curious and elegant curves, been in operation throughout all these changeful phases. that gave a new lease of life to my course of experiment. It may be imagined how intricate the web becomes, Before attempting anything, I drew in my pocket-book though the limits of illustration do not allow me to give a the skeletons of the curves that would be described corre- specimen here. It was easy to eliminate all the transisponding to the proportions, 1:2, 2:3, 3:4, 4:5, 5:6, tion-curves from the tracery, by depressing the paper for 6:7, 7:8, 8:9, in the periods of quick and slow vibra- the proper interval, and allowing it to return to contact tion. Then I hung a bullet by two threads from two with the pen only at those distinctive phases when the points about ten inches apart on the circumference of a original figure was reproduced either ere:t or reversed. child's wooden hoop, fixing the hoop upright with the obtained a very curious specimen by applying this bullet swinging inside the circle. Another bit of thread selective method to the case of the proportion 1 : 2, allowfurnished the sliding-ring to nip the two convergenting the pen to mark only the crescents and the figures of threads at any desired point, and a few trials enabled me 8 in alternate series, converging orderly to the centre. to fix it pretty accurately for the proportion 1 : 2, so that For the suspension of the paper, I fixed four pairs of the bullet would swing in the plane of the hoop in half upright rods at the four corners of a shallow tray, which the time it took to swing at right angles to the plane of could be slipped under the pendulum, and each rod gave the hoop, making two vibrations in the plane of the hoop support to an india-rubber band, which, with its fellow at to one vibration athwart. (The length of the pendulum right angles, was attached by a small hook to the correvaries as the square of the period of vibration, so the sponding angle of the paper. Each bind could be slid up slider was at a point one quarter of the dissance from the or down its rod, to allow of nice adjustment of the level of bullet to the horizontal line between the two points of the paper, and ihe whole tray could be raised on a footsuspension.) It was with great interest that I watched stool or chair, to suit the elevation of the pendu uin when the motion of my pensile bullet, and greeted the verifica the slider was run aloft in attaining the proportions nearer tion of my pocket book sketch. Pull the bullet aside and unity, such as 7 : 8, or 8 : 9. start it obliquely, and it describes a crescent-moon, the The iron chain was soon exchanged for strong cords, two horns being formed by the double sving in the plane passing through a narrow wire ring, which could be arof the hoop, while the length of the crescent measured rested at any point by a needle driven through both cords from tip to tip is given by a single swing athwart the below the ring. This was a small improvement, allowing plane of the hoop. Start the bullet from rest at the centre more accuracy in the adjustment of the slider, and thereby a sudden blow obliquely given, and it describes a figure fore more accuracy in the proportion between the two of eight with its length athwart the plane of the hoop. periods of quick and slow vibration. But it was still (See Figs. 5 and 6.) Other proportions gave still more very far from satisfactory. Meanwhile I had ordered curious results in accordance with my skeleton sketches, a cylinder of lead, weighing half a cut, to be cast, and made me impatient to try them on a larger scale. with a hole through the axis; for my zinc box full The lead at my command I packed into a long-shaped of “notions ” so tall that I could not bring zinc box, with a tubular orifice at the top, which in my the slider near enough to the centre of gravity to obtain service became the bottom. To the lead I added a stone any proportion lower than 1 : 3, and that only with great jar containing some 10 lbs. of mercury, and made every trouble. When the cylinder of lead appeared, I sawed it ihing secure with cordage. The dependent tubular orifice into two unequal portions, so that I could use either or seemed made on purpose to accommodate a few inches both ; and instead of simple cords, which twisted in a of wooden roller which carried the glass pen, and a most troublesome manner below the sliding ring 1 introdiagonal beam in the ceiling of my bedroom offered a duced a stiff rod of fir to carry the lead by a cross pin, capital fixture for two rings about four feet apart, giving and I used two pairs of cords passing through holes in a suspension to two iron chains by which my incongruous slider on either side of the central rod. This slider was a pendulum-bob was doomed to swing. To nip the chains small block of wood pierced to fit the rod, and provided together at i he requisite height, I used a loose link which with a lateral screw to fix it at any required height. This hooked into the corresponding links in the two conver- arrangement ensured admirable steadiness and freedom gents, and made a very rude and coarse adjustment, which from torsion, and a great many sheets were filled with the ieft all accuracy to chance. It chanced, however, that improved performances of the machine ; but there still the adjustment for the proportion 2:3 was beautifully reinained an important defect to remedy. The coarse accurate, and I shall never forget the feeling of delight cords, at the point where they entered the holes in the which I experienced while watching the marvellous slider, made a very rough hinge for the cross vibration to fidelity with which the pen.point traced the curve appro- rely upon, and it was manifest in the tell-tale records of priate to that proportion. The pendulum was drawn the curves described that considerable change of period aside and started obliquely on one side of the plane of took place between the beginning and the end of the web; slow vibration, and having to make three vibrations across and the change was always such as to increase the disthat plane to two vibrations to and fro, it compounds these parity between the two periods, which could only mean into a curve like a capital Q with two tails, one on each that the level of the centre of quick vibration in the cords side, looking like a swallow-tailed balloon. (See Fig. 9.) immediately above the slider was lowered when the range

:

was

of oscillation diminished. It was easy to see that a large slider and the centre of gravity must be 1-16th of the oscillation would strain the cords to a greater height above height of the pendulum, or only six inches in the present the slider than would be called for in a smaller oscillation. instance; but three or four of those six inches are taken The truth of this surmise was proved by the success of the up with the thickness of the lead and the attachments of remedy applied. Instead of cords I used two pairs of the tapes, and the rest with the depth of the slider, and broad tapes, and instead of a solid slider I made one in so the curve cannot be obtained without a more lofty two halves, embracing the rod in the centre and nipping suspension for the pendulum. This greater elevation the concurrent tapes on either side between their opposed I found in the great octagonal room which Sir Christofaces, being clamped together by thumb-screws beyond pher Wren built as the chief room of the Royal the tapes on either side. Here the slider had no firm Observatory in Greenwich Park. By means of two hold on the rod beyond the accuracy of its fit, which hooks fixed above opposite windows in this room,

from served to prevent torsion, but had firm hold on the pairs which my tapes converged to the middle, I got a of tapes, pinching them with especial accuracy at the height of eighteen feet, and was able to reach such proupper edge of the slit in which they lay between the two portions as 1 : 4,1:5,!:6. At this extreme it was really halves, and reducing the hinge there to a narrow line no amusing to watch the busy haste of the manifold crossthicker than the pairs of tapes instead of the gross thick- vibration over-riding the staid gravity that marked the ness of the cords which they superseded. The improve- slower oscillation to and fro. To obtain proportions lower ment of the pendulum's performance on paper was very yet than these, I should want a great increase in height of striking. When well adjusted, it was scarcely possible suspension ; but there is no great inducement to attempt from beginning to end to detect any change in the shape this, as the nature of the curve may be foreseen at a glance, of the figure described ; scarcely possible, I say, for even and is marked by extreme simplicity-merely a zigzag or now our hinge is not a mathematical line, and we do not a string of beads. obtain perfect mathematical accuracy in our results. Some of these experiments with losty suspension were Further improvement might be obtained by refinement in made on stormy days; and while watching the travels of tapes and slider, or by increasing the total height of the the delicate pen-point, I could see that their regularity pendulum, or by substituting some other form of hinge; was slightly disturbed by every gust of unusual violence but the form which I have described is so simple, and its that beat against the high walls. performance so good, that I am content to accept its one But this article would never end if I allowed myself to very small fault for the sake of its many excellent dwell on all the points that called for attention in the qualities.

course of experiment which I have been describing. I Figures 1-12 are the produce of this pendulum thus fear I have exceeded due limits already, and feel that I improved. They are only a few of the most interesting owe an apology to the reader for so large a trespass on his out of an endless variety of interesting curves, and are patience. My apology must be the elegance and exquisite chosen as characteristic specimens of a series too exten- symmetry of these natural curves in their admirable obesive to be fairly represented except by a much larger dience to a purely natural law, and the great pleasure I number of illustrations. Figures i and 2 represent the have enjoyed-the sense of high privilege I have fet-in proportion I : 3, the lowest that is easily attainable with their investigation. I understand that these curves, or out a loftier pendulum ; and the following pairs of figures some of them, have been demonstrated before, by means show successively the proportions 2:5, 1:2,3:5, 2:3, 3:4. of a stream of sand flowing from a hole in the base of a Each of these is illustrated by two figures exhibiting vessel that was used as the weight of the pendulum, and the two chief types of the curve proper to that propor

I believe that steel springs of elliptic or oblong crosstion. They may be termed the cusped type and the section have been made to trace such curves as that which looped type. It will be seen that the two cusps in the first attracted my attention in the vibration of my slender first figure of each pair are opened into loops in the acacia-twig ; but I am not aware that any specimens of second, and that each loop in the first is doubled in the the series have ever before been exhibited in a form that second. Between these two typical forms we have an rendered them accessible to the public eye. infinite series of intermediate forms possessing features

HUBERT AIRY of great interest, those nearest the cusped type especially being characterised by a peculiar“ watered” appearance, due to the intersection of two sets of lines very slightly

SOME SPECULATIONS ON THE AURORA inclined to one another. This is seen, for example, in Fig. 3, which errs a little from the perfect type.

IN preparing a lecture on the Aurora Borealis some

months ago, I was led to some speculations which may Accuracy of proportion between the two periods of

or may not be new, and may or may not be of some value. vibration could only be arrived at by repeated trials. I will submit them to the readers of NATURE. The sliding-clamp sufficed for coarse adjustment, but for I assume of course that the auroral rays extend to great fine adjustment it was found necessary to attach a sub- heights above the surface of the earth, that they are sidiary weight below the large one in some way admitting sensibly parallel, and that their apparent point of conof considerable range of position, so as to alter minutely vergence is, generally speaking, that to which the freelythe position of the centre of gravity. A heavy iron nut

suspended magnet points. In the great aurora of October travelling easily on a screw-thread cut on the depending 24, 1870, this point was close to n Pegasi at 8.30 P.M., coshaft that carried the pen supplied this want, and greatly inciding very well with the direction of the magnet. facilitated the attainment of the utmost accuracy at com- Remembering that this aurora was witnessed over a large mand.

part of the northern hemisphere, and that there was a With a pendulum only seven or eight feet high, there contemporaneous aurora in the southern hemisphere, and, is great difficulty in obtaining the curves that correspond assuming that at each place the direction of the auroral to any proportions lower than I :3, because the slider streamers is approximately parallel to the magnet, we must cannot be brought within a certain distance of the centre conceive the earth, during such an auroral display, as a of gravity, which lies somewhere in the middle of the globe with streamers of light radiating and diverging from lead. To obtain the proportion 1 : 3, that is, to make

its polar regions, and spreading far out into space. The the pendulum swing three times across for every one general direction of these streamers at different spots on swing to and fro, we must lower the slider within a foot

the earth will be got by placing a magnet below a sheet of of the centre of gravity (the length of the pendulum paper and getting the magnetic curves with iron filings, varying as the square of the period of oscillation), and to obtain the proportion 1 : 4, the distance between the

* To-night it is a few degrees below a Cygni (but not clearly defined) at

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and then describing a circle, to represent a section through double number of the American Naturalist for September 15 will the axis of the earth so that the magnet shall occupy the give a full report of both the opening address and the sectional central part, about two-thirds of its diameter. The por- proceedings. In a future number we shall give an epitome of all tion of the magnetic curves outside the circle will cut the

matters of interest discussed at the meeting. circle at different angles, and fairly represent the directions of the auroral streamers.

M. JANSSEN has been commissioned by the French Govern. Now, Arago, in his catalogue of auroras, shows that ment to proceed to the East to observe the total Solar Eclipse of during the months of September, October, March, and December next. He has, therefore, been compelled to decline April we are especially favoured with auroras ; and that the offer made to him by the British Association to take part in in these months they are both brighter and more frequent the British Expedition. than at other times. This periodicity indicates an extra terrestrial origin for auroras. Does it not show that

The President of the Royal Society has received a telegram during those months we pass through an auroral region,

from the Government Astronomer, Melbourne, that the Eclipse just as in November and August we pass through meteoric Expedition will leave that port on November 20. regions, or, in other words, that we intersect a ring of some

We regret that owing to the omission of a sentence, the note substance capable of being electrified by the earth in its respecting the distinguished visitors at Section A of the late passage, when there is any change in its magnetic power, and so rendered luminous? But it is impossible not to con

meeting of the British Association, read incorrectly in a small jecture that this ring or disc is the very disc which is

proportion of the edition of our last number. We now supply visible to us as the zodiacal light; for besides the fact of zodi- the omission by giving the following probably unexampled list of acal light being specially visible during the same months,

Senior and Second Wranglers and Smiths' Prizemen who were there is the positive evidence of spectrum analysis to the present :--Adams, Cayley, Challis, Stokes, Hon. J. W. Strutt, identity of the substances luminous in the aurora and the Hopkinson, Kelland, Tait, Wilson, Thomson, Maxwell, zodiacal light. We are led then to the hypothesis that Sylvester, Clifford, Jack, J. W. L. Glaisher ; of these the first there exists round the sun, and extending as far as our nine were Senior Wranglers. earth, an atmosphere, consisting of an unknown element, a gas of extreme lightness, and that this atmosphere is

We learn from the British Medical Journal that in accordance especially condensed in the form of a disc extending round

with the will of the late Dr. Lacaze a prize of 10,00ofr. is to be the sun, but probably not concentric with it. The same awarded by the Faculty of Medicine of Paris every second year element appears to exist in the solar corona, and was also to the best work on phthisis and on typhoid fever alternately. detected in the vague phosphorescent luminosities of the The first prize will be awarded at the end of the academical year sky on a particular evening, by, I think, Angström. 1871-2, for the best work on phthisis. Essays (with a distin

I wish to suggest, therefore, that catalogues of auroras guishing motto and the author's name in a sealed envelope) must may, like catalogues of meteors, determine auroral regions

be sent in before July 1, 1872. The prize is open to foreigners. in the earth's orbit, and that two such regions are, in fact, already shown by Arago's catalogue, and that this periodi- In a paper read before the Natural History Society of Boston city, as well as the results of spectrum analysis, indicate a (U.S.), Mr. W. T. Brigham gives an account of several remarkcosmical origin for auroras.

able earthquakes that have occurred in New England, with a list There is one more point which may be interesting. The of all such phenomena that have occurred in that region from luminous streamers have a lateral motion; they shiit side

1638 to 1870. Some of these disturbances appear to have been ways, and in fact rotate round their pole. Is this motion

violent and protracted. of rotation always, or even generally, in the same direction? I have not observed it often enough to speak with

We understand from the Geological Magazine that there will confidence. But if so, it must have some definite cause,

shortly be published a Geological Atlas of England, by Mr. W. and will be analogous to that of rotation in a definite Stephen Mitchell. The Atlas will contain the following Maps :direction of an electrical current round the pole of a 1. Cambrian (of Survey); Lower Cambrian (of Sedgwick). magnet. The earth must be looked upon as a delicate 2. Lower Silurian (of Survey) ; Middle and Upper Cambrian solar electroscope and magnetometer, and the electrical (of Sedgwick). 3. Upper Silurian (of Survey); Silurian (of discharge round the earth is stratified, and is in lines and

Sedgwick). 4. Old Red Sandstone ; Devonian. 5. Carbonstrata that have, perhaps, motions in definite directions.

iserous Limestone ; Yoredale Beds. 6. Millstone Grit; Coal It may be worth remarking that the 22nd, 23rd, 24th, Measures. 7. Permian (of Survey) ; Pontefract Group (of Sedgand 25th of October are the most famous days in the year wick). 8. New Red Sandstone ; Rhætic (Penarth). 9. Lias. for auroras, at least in the present century, and that the greatest displays of all on those days have happened at

Lower Oolite. 11. Middle Oolite. 12. Upper Oolite. intervals of multiples of eleven years. Last year we had

13. Wealden ; Neocomian. 14. Gault; Upper Greensand; splendid auroras on the 24th and 25th ; there is, there- Chalk and Chalk Marl. 15. Eocene. fure, some ground for expecting fine auroras on the same luvium. 18. Bone Caves. 19. Metamorphic (?) 20. Igneous. nights this year, if the auroral cycle corresponds to the The Maps will be printed in colours, each Map exhibiting only sunspot and magnetic cycles.

J. M. Wilson the range of one formation, and the names of places on the for

mation. In some few cases, where it is requisite, as a clue to

the locality, to introduce the names of places near, but not on, the NOTES

formation, these will be printed in a different type. The Maps We learn from Indianapolis journals, received at the moment (ufin. by 9}in.) are based on a photographic reduction of the of going to press, that the American Association for the Advance- last edition of the Greenough Map, which is published under the ment of Science commenced its sittings on the evening of August direction of a committee appointed by the Geological Society. 21 by an opening address from the retiring president, Prof. T. In all cases where, through researches more recent than this last Sterry Hunt, on the Iron Interests of Indiana, in which he com · edition, any changes have been adopted in the grouping of the pletely sustained every claim that had been made for the State, beds, this atlas conforms with the latest alterations. The revision showing conclusively that it has the elements within its borders of the proofs of particular maps has been kindly promised by from which to secure a manufacturing future that shall make

Mr. W. Boyd Dawkins, F.R.S., Mr. W. Whitaker, Mr. H. Indiana the mediterranean workshop for the whole country. The Bauerman, Mr. J. W. Judd, Mr. Charles Moore, Mr. W. T. sections commenced their sittings on the following day, and San Aveline, and others. Letter-press will accompany each map, Frar.cisco was fixed on as the next place of meeting. An extra giving in a tabulated form the subdivisions of the formations, the

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origin of the names of the groups of beds, their lithological Mr. Joseph Stevens, M.D., “On newly-discovered Roman and characters, thickness, range, &c., with a historical notice of the Saxon remains at Finkley near Andover.” The meeting was various classifications that have been at different times employed. brought to a close on Saturday evening. Saturday's excursion was The lists of fossils will be arranged on a new plan, showing in a first by rail to Bindon Abbey, thence to Wareham, and afterwards tabulated form for each formation the genera that first appear, by rail to Corse Castle. The concluding meeting was held at the those that last appear, and those that are numerically abundant Royal Hotel on the return of the excursionists to Weymouth, at in that formation. Separate tables give the characteristic 8.30, when, after the reading of some papers, the usual formal species. These lists are prepared expressly for this work by Mr. resolutions and votes of thanks to the gentlemen who had assisted R. Etheridge, F.R.S., &c., Palæontologist to Her Majesty's the Association in conducting the proceedings were passed and the Geological Survey of Great Britain.

congress was brought to a close. The continental scientific journals record the death of Dr. The Annual Meeting of the Devonshire Association for the Milde, a well-known botanist, whose contributions to systematic Promotion of Literature, Science, and Art, recently held cryptogamic botany are especially valuable.

its sittings at the picturesque little town of Bideford, We have to notice the death, at a very advanced age, of occupying three days, the retiring President, Mr. J. A. Froude, James De Carle Sowerby, the first secretary of the Royal Botanic resigning the chair to the Rev. Canon Kingsley, who gave an

eloquent and interesting address. Papers were read, mostly of Gardens, Regent's Park, an office which he held till last year,

an archæological and geographical character, by Mr. Pengelly, when he resigned it in favour of his son. Mr. Sowerby be.

Mr. Spence Bate, and other distinguished Devonians. longed to a family, many members of which have distinguished themselves by their devotion to various branches of science, and Ir is stated that Prof. Watson, of the University of Michigan, to the pictorial illustration of natural objects.

has discovered a new planet in the constellation Capricorn, of the THE Essex Institute publishes an obituary notice of its late

tenth magnitude. This is the 115th of the series. president, Mr. Francis Peabody, of Salem, who died October MR. J. R. HIND, F.R.S., has calculated the Ephemeris for 31, 1867, and who was noted for his researches in mechanical | Greenwich mean time of Futtle's Comet, which will be visible physics.

during this and next month. According to Prof. Luther, its next The trustees of the Manchester Grammar School are so satis- perihelion passage will occur about the 30th of November. The fied with the excellent work done in the Physical Science De

following are Mr. Hind's figures :

1871 partment, under the superintendence of Dr. W. M. Watts, that

Declination.
Right Ascension.
Sept. 1

100° 13'2' they have begun to fit up a second and larger laboratory, at the

62° 22°7' 7

106° 36'6' 60° 55'6' cost of from 700l. or Sool. It is only three or four years since

15

115° 12:8 this department of the school was opened, and already many

58° 2007? 23

122° 38.8' valuable scholarships and other honours have been gained by the

54° 59:8' Oct.

129° 15.7" boys.

50° 49'5'

7 133° 44'3' 47° 26' The following eminent archæologists are announced as con

13 137° 51°5' 42° 35'5' tributing papers for the next session of the Society of Biblical Archæology :-M. Heinrich Brugsch, F. C. Chabas, Clermont Prof. A. HALL sends us some careful Equatorial Observa. Ganneau, and the Chevalier de Sauley. The first part of the tions made at the U.S. Naval Observatory, Washington, and society's transactions will be ready early in the spring, and will Supplementary Notes on the observations for magnetism and cuntain articles by Dr. Birch, J. W. Bosanquet, M. Ganneau, position made in the U.S. Naval Observatory expedition to Prof. Lowne, Lieut. Prideaux, G. Smith, and H. Fox Talbot. Siberia to observe the Solar Eclipse of August 7, 1869.

The Society of Arts have consented to give their co-operation A RECENT number of the “ Astronomische Nachrichten” to the Polytechnic Exhibition, to be held at Moscow next year, contains an elaborate paper by Prof. E. Schönfeld, “On the in celebration of the two hundredth anniversary of the birth of Change of Light of Variable Stars.” Czar Peter the Great.

The Journal of the Society of Arts states that a memorial According to recently-published statistics of the University monument has been erected in New South Wales to the memory of Edinburgh Botanical Class, in the session of 1871 the of Captain Cook, at the supposed place at which he landed from number of pupils was 306. Of these, 241 (including 5 ladies) the Endeavour in April, 1770. On the monument are two brass were medical students, 12 pharmaceutical students, and 53 plates, one bearing the following inscription :-“Captain Cook general students.

landed here 28th April, 1770. Victoria Regina. This monument The Archäological Society, whose gathering at Weymouth

was erected by the Hon. Thomas Holt, M.L.C., A. D. 1870. The we recorded last week, devoted Wednesday to an examination of Earl of Belmore, Governor.” The other contains the following objects of antiquarian interest in that town, including the Cor- words from Captain Cook's journal :—“We discovered a bay and poration regalia and muniments. On Thursday papers were

anchored under the south shore, about two miles within the read as follows :-By Mr. H. S. Cuming, F.S.A., “On the entrance, in 6 fathom water, the south point bearing S. E., and Patron Saint of Dorset, St. Edward, King and Martyr.” By he north point east. Latitude 34' S., longitude, 208-37°.” The Mr. J. Drew, F.R.A.S., F.G.S., “On Art Treasures and their entrance to the bay where Cook landed has other memorials, preservation.” By Mr. G. Eliot, “On the Antiquities of Port- On the north side is the column erected, on behalf of the French land." There was afterwards an excursion to Corfe and Dor- nation, to the French navigator, La Perouse. The enclosure chester, visiting several objects of interest on the way. The around the column is planted with trees and flowers. The monu. papers read on Saturday and Friday evenings were as follow :- ment erected by Mr. Holt is on a place less elevated, but it can, Mr. J. R. Planché, Somerset Herald, “On the Family of Robert nevertheless, be seen from several parts of distant suburbs. Fitzgerald, the Domesday Tenant of Corfe.” Mr. Edward Public subscriptions are being made for a monument of a more Levien, M.A., F.S.A., Hon. Sec., “On Wareham and its costly kind, to be erected in one of the parks of the city of Religious Houses.” Mr. W. H. Black, F.S.A., “On Wareham Sydney. and the Earliest Historic Monuments in Dorset.” Rev. William The last number of the Bulletin of the Société d'Acclimata. Barnes, B.D., "On the origin of the name and people of Dorset." tion of Paris contains an interesting and important report on the

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International Fishery Exhibitions of Boulogne, Arcachon, and
Havre.

THE BRITISH ASSOCIATION MEETING AT At the recent annual meeing of the Royal Cornwall Institu

EDINBURGH tion, a discussion arose on a paper read by Mr. Robert Blee

SECTION A. On the Comparative Health and Longevity of Cornish Miners," in the course of which the startling statement was Report of the Tidal Committee, by Sir W. Thomson. made, that a death occurred every other day among the Cornish He stated that the work performed for the Tidal Committee miners from the mode in which the men were raised from the since the last meeting of the British Association had consisted pits.

chiefly in the evaluation of tide components in a similar manner

to that described in the previous reports. Mr. Parkes having Prof. DANIEL Wilson, of Toronto, publishes in the again placed the tracings of the curves of the Kurrachee (Manora) Canadian Journal an essay on The Huron Race and its Head- self-regulating tide gauge at the disposal of the committee, á form,” illustrated with a lithograph and many outline drawings.

second year's observations had been read off and completely reProf. Wilson's investigations lead him to believe that the com

duced. In addition to the tide components evaluated for Liver

pool and Ramsgate, others had been introduced to correct the prehensive generalisations of earlier American ethnologists, un.

lunar diurnal (declinational) tides for parallax. Those components der the guidance of Dr. Morton, which led to the doctrine of a had been found to have sensible values for Kurrachee, where the homogeneous cranial type for the American aborigines, have diurnal tides are comparatively large. The solar elliptic semieverywhere failed when subjected to the crucial tests of detailed diurnal components had also been included, now that two comobservation, and that we everywhere find transitions from one to

plete years'observations were available. The comparison between

the calculated and recorded heights from Liverpool not being another and essentially distinct ethnical group. There is, he

considered as good as might have been expected from the labour concludes, no longer an assumed American man, as distinct from bestowed on them, it was determined to continue the analysis of every type in the Eastern Hemisphere as the Catarhine Simiadæ the Liverpool tides, with the view, if possible, of detecting the of the Old World from the Platyrhine group of New World cause of the largeness of some of the differences. It would be monkeys.

seen on comparing the results contained in the previous report

with the results arrived at, that the chief tides (the lunar and On Monday, August 21, between three and four o'clock in solar semi-diurnal) are now more retarded by about 4° than dur. the morning, a large waterspout burst over the village of Ollon ing the year previously analysed. The calculated heights in the and the adjacent mountains in Switzerland. Great damage was

comparison should therefore more nearly represent the heights done to the roads and vineyards, but no loss of life is reported.

about eight minutes after the hours assigned to them. An ex

amination of the differences would show this to be the case. А A VIOLENT hurricane and some earthquake shocks are re

fresh calculation and due allowance made for atmospheric pressure ported from the Island of St. Thomas, in the West Indies, on would doubtless very considerably reduce the discrepancies. The the 21st of August. Hundreds of houses were destroyed, and

gradual increase in the height of the mean level of the water,

probably arising from the filling in of the bed of the river, and over 150 persons killed or wounded.

consequent increase of friction, would account for some portion From Indian sources we learn that the rainfall in Bombay

of this increased retardation. There was a very violent rise in this season is generally less than half the average of former years.

the mean level for the year 1868-69, amounting to four-tenths of

a foot. It, however, in the following year, had again subsided A VIOLENT typhoon raged at Kobe in Japan, on the 4th to almost its anticipated height. The uncertainty in the mean of July. Many vessels were wrecked, and about 400 lives were

level of the water is an element which must at times seriously

affect the differences between calculated and recorded heights, in lost. Great damage was done to property on sea and on land.

any method of computation of heights from a fixed datum. It The news of most terrible earthquake shocks and volcanic dis- was very much to be regretted that the authorities at Liverpool turbances cumes to us from the Philippine Islands. In the small had chosen the George's Landing-Stage for a tide float, affected

as it must be (sometimes to a considerable extent) by the ever. island named Camiguin, near to Misamis, sor some months past

varying weight it has to bear. This would affect the whole of a succession of most violent earthquakes has been experienced,

the tide components evaluated, but more especially the solar causing crevices, &c., in the open country. On the 1st of May, components, and will account for the different values of the solar about five o'clock in the evening, the earth burst asunder, and an semi-diurnal tide, which, judging from the corresponding lunar opening was formed 1,500 feet long, Smoke and ashes, earth component, should agree within much narrower limits. It was

therefore thought that, should it be determined to again discuss and stones, were thrown up and covered the ground far and near.

the Liverpool tides, it would be better to take the tide curves as At about seven o'clock, as darkness was coming on, this crater

self-registered at Helbie Island, at the mouth of the Dee, in preburst into activity with a loud explosion, followed by a shower of ference to those of the George's Pier. The Helbie Island tide lava and ashes. About 150 persons were destroyed. The curves, it was considered, would give much superior results. eruption of the new volcano has since been so tremendous that

Through the kindness of the United States Coast Survey Office,

two years' tide observations, taken at Port Point, San Francisco the inhabitants have forsaken the island, and of the 26,000 pre

Bay, California, had been received. llere again there was an viously there, not 300 are left. Camiguin is only about thirty

abrupt diminution in the height of mean level for the first two six miles in circumserence, and was very productive in abacá (the

years.

It having come to the knowledge of the Tide Committee Manilla hemp) yielding annually from 30,000 to 40,000 piculs, or that the United States Coast Survey Office were in possession of more than a tenth of the produce of the world. There is little

a series of lourly tidal observations, taken at Cat Island, in the

Gulf of Mexico, and which were of a very remarkable and inhope of the island ever being again reoccupied or cultivated.

teresting character, it was thought a favourable opportunity of The American Journal of Microscopy recommends, as the testing the value of the harmonic analysis for the evaluation of best plan of collecting diatoms in large quantities, to tie a thin,

the components of the tides of this place, which appeared very fine piece of linen over the faucet of the hydrant in the evening,

complicated and peculiar. Application having been made, a

series of about thirteen months had been received, and were now and allow a small stream of water to pass through it all night.

in course of reduction. It was extremely interesting to find that, In the morning take off the cloth and rinse it in a little water in although the lunar and solar semi-diurnal tides were very small a goblet. When ready to examine, take a drop of water from in value, the series of means from which they were obtained were the bottom of the goblet with a small pipette, or glass roll, and extremely regular and go, and the consequent determination of place it on a flat slide, or a slide with a concave depression, bably correct within a few minutes. The proportion between the

the phase of spring tides from their respective epochs was proholding a few drops. Then, with a power of 100 or 350, sweep amplitudes of the lunar and solar semi-diurnal tides was the the field, and you will be rewarded with the sight of a wondrous

nearest to equality yet obtained, being in the ratio of 1 to 6. collection of beautiful and unique forms.

The proportion between the lunar and solar diurnal (declinational)

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