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Here is a perfect demonstration evident to the senses. But let be of the utmost value to thousands who would never attempt to us go one step further. The rectangles in the preceding theorem learn “Euclid ;” whilst, so far as I am able to judge, it is more may be bisecied by diagonals and set round the square of the likely to prepare the boy to read formal works on geometry with difference in such a manner as to form the square of the hypo- pleasure than to create a distaste for the study. thenuse of the right-angled triangle, the sides of which are also

THOMAS JONES those of the assumed squares. The squares of the sides of a right- Woolwich, October 9 angled triangle, therefore, are together equal to the square of the hypothenuse, since the former may be changed into the latter.

The Coming Eclipse I have been very much interested in Mr. Lockyer's lecture at the Royal Institution on the late eclipse. I am especially glad that he is at length able to acknowledge the existence of comparatively cool hydrogen, because in my Eclipse Report of 1868 (vol. xxxvii. Part 1, R.A.S. Memoirs), I stated that I believed from the evidence of the photographs that hydro. gen was dispersed from the prominences in visible streams in some cases, and in others invisibly.

But while Mr. Lockyer admits this, he seems to me very unnecessarily to avoid everywhere the use of our familiar term

“ atmosphere” to include the whole gaseous envelope of the The same conclusion may be arrived at by a still shorter and This seems to me to be the sense in which Kirchhoff used simpler course. Let any two squares be joined together as in the word when he said it was extensive. * It certainly was the the annexed figure, or, rather, let them be cut in paper in one sense in which I used it, and, I believe, that in which all who piece. Then take a c equal to the side of the greater square,

spoke of an extensive atmosphere did so use it. In this sense and join b c and ce. Cut off the two equal triangles bac and there can be no doubt that the sun has an extensive atmospbere, cde, and place them in the positions of b m f and f n e, and the the outer portion of which is comparatively cold and capable of two squares will be thus transformed into the square of the reflecting light if the polarisation now not doubted be due to hypothenuse of the right-angled triangle, of which they form the reflection. sides.

There is one consideration which, however, does not seem to Thus we have at once a demonstration of the famous Pytha- have occurred to Mr. Lockyer. If the cold atmosphere, as I gorean theoiem (Euclid i. 47), and have attained with three or will venture still to call it, reflect the prominence light, it will four steps the same height climbed by Euclid with forty-seven. also reflect the solar light. Its reflected light then should te The words of his demonstration, committed to memory by a

such as reaches us at ordinary times, and not so exclusively child, remain there mere words and nothing more.

Words chromospheric. Adding to this the light which is due to cool serve to mark and denote ideas, but cannot create them, where hydrogen, we should have, I anticipate, a faint continuous spec. the material of ideas does not already exist. But the child who trum with the bright line F, and also a solar spectrum withi

, with paper or card amuses himself in going over the visible de perhaps, some of the chromospheric lines reversed. That is not monstration suggested in this letter, in various forms and re

what has been found, and I do not at present see any way of peatedly-for neither old nor young can be said to learn a truth reconciling the facts with the theory that the undoubted polarisamerely by its transient recognition will assuredly awaken to an tion is due to reflection. agreeable consciousness of the reasoning faculiy, and feel no Before going to another subject, I would wish to direct attendifficulty in future geometrical studies.

tion to my friend Captain (now Major) Branfill's observations in In 1860 there was published for me, by Messrs. Williams and 1868+ on the polarisation of the corona. Mr. Proctor, indeed, Norgate, a little volume entitled, “The Elements of Geometry in his book on the Sun, says that the Astronomer Royal did not Simplified and Explained,” adapted to the system of empirical consider them conclusive, but I have his official statement that proof, and of exhibiting the truth of theorems by means of he did so consider them, and an inquiry as to Mr. Proctor's figures cut in paper. It contained in thirty-five theorems the quint authority leads me to think that Mr. Airy's meaning was misessence of Euclid's first six books, together with a supplement of taken. I think any one who reads the account in ihe original thirty-three not in Euclid. There was no gap in the sequence or

will feel that the plane of polarisation was satisfactorily deter. chain of reasoning, yet the 32nd and 47th provisions of Euclid mined. An observer in 1870 has said that he found the bands were respectively the 3rd and 17th of my series. This book of Savart persistent. I have not now time to look up the proved a failure, for which several reasons might be given, but it reference, but he used, it seemed to me, the centre of the moon will be sufficient here to state but one, namely, that it came forth

as the centre of rotation. Captain Branfill was careful not to ten years before its time. What became of it I know not. But of do this, as his figures prove (page 25 of Report). this I am convinced, that though I failed, success will attend

Now to the future. "I have received from Government an inthose who follow in my footsteps.

W. D. COOLEY quiry as to recommendations to observers coming out. I am

now suggesting, in addition to my own station at Dodabetta, that

observers should be stationed at Kotagherry in the Nilgherries, The discussion in your last part on methods of teaching Tirupur, close to Avenashy Road Station of the Madras Railway,

at Manantoddy among the coffee districts to the west, and at elementary geometry reminds me that at a period when I was teaching the subject to a considerable number of pupils, I fre

Of these Manantoddy is the least accessible, but the whole will quently overcame the difficulties of very young or inapt students give a range of stations from 8,600 feet high down to the by commencing with the study of a solid, such as a cube, en

ordinary level of the plain country. More observers could be couraging the pupils to frame definitions for the parts of the

accommodated on the Nilgherries, where the weather, I am object. The ideas existing in the child's mind of a solid, a plane, assured, is likely to be excellent. Of Ceylon I have not satisa line, and a point, were thus put into words in an order the factory accounts, nor of the west coast. reverse of that in which they would have been had Euclid been

If these stations be adopted, I would suggest that, if possible, used. The chief properties of parallelograms and triangles fol

there should be a conference of observers. The possibility will lowed, and were easily discovered by the use of a pair of com

depend on our leisure, which, probably, none of us can now passes, scissors, and paper, and that at an age when Euclid was a sealed book. I believe children can be most easily taught to

I should say that I have made these suggestions without solve problems in plane geometry when they occur in connection

reference to Mr. Pogson, because I know nothing of his plans, with early instruction in practical solid geometry. Most children having received no answer to inquiries; it is possible those may try to draw, and if they were encouraged to represent simple modify projects, but any visitors should bear in mind that it is objects by "plans” and “ elevations," the necessity of obtaining almost necessary that some European residences should be close a knowledge of how to describe the forms presented to them

to their stations.

J. T. TENNANT would frequently carry the pupils through a large number of the

H.M. Mint, Calcutta, Sept. II principal problems of plane geometry with a pleasure they could * Mr. Lockyer has long ago shown that the Sun's atmosphere lies partly not experience if the problems" were put before them, without

above and partly below the superior limit of the photosphere. The word

Atmosphere was used by Kirchhoff in the manner indicated, because he any reason for their solution but the teacher's command. The

believed the photosphere to be liquid.-ED. powers of truthful representation gained by such teaching, would † American observers seem never to have seen the Report.

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British Mosses

a sphere varies as the cube of the radius, and therefore that on Not having noticed in the last number of NATURE, Oct. 12,

the data assumed by him the earth's atmosphere raised to the any correction made by either the Rev. Mr. Berkeley or Dr. Dickie, temperature of the solar surface, instead of attaining a height of of a statement made by the former gentleman in the previous | 279,006 miles, would barely reach to one-twelfth of that limit

. number, Oct. 5, which, as it reads, is calculated to lead to error,

But I may further remark that the assumptions on which Mr. if left unnoticed, I send you this note.

Ericsson's calculations are founded are open to many objections. In the short paragraph at p. 446, “Notaris on Mosses,” Mr.

It is far from certain that the direct proportion between the inBerkeley, in correcting a previous omission having reference to the

crease of volume of gases at constant pressure and the increase of genus Habrodon, states that Conomitrium julianum had been temperature, holds good for an enormously high temperature sent to Dr. Dickie by Mr. Wilson from his district,” Warrington. such as prevails in the solar atmosphere, and it is certain that This being only one side of the truth, I take the liberty of supply: heat depends not solely or mainly on its temperature, but on its

the resistance offered by that medium to the passage of radiant ing the other side. Any person reading the paragraph as it stands would certainly suppose that this very elegant, and very

chem cal--1.6. its molecular-constitution. remarkable moss was a native of the Warrington district, which

It may further be noted that Mr. Ericsson's experiments on the it is not, nor of any other part of the British Isles that I am aware

diminution of heat emanating from a disc of incandescent iron, of. No doubt Dr. Dickie received fresh specimens of the moss

according to the angle at which its face is inclined to a fixed from Mr. Wilson at Warrington, as I also did, but they were of thermometer, do not justify similar conclusions with regard to foreign origin, and only cultivated by Mr. Wilson in his little | heat emanating from a mass of incandescent gases or vapours. conservatory at Warrington, where he had them placed in a large

At the same time it may be regretted that Mr. Ericsson has not mouthed jar filled with water, in which condition I saw the given fuller details respecting the experiments in question, which plants during the month of October, 1870, on the occasion of the may give valuable results irrespective of the conclusions to which last visit I paid to my now departed friend.

he has applied them.

JOHN BALL I may fur.her remark that I had been led to suppose it was Dr. Schimper, of Strasburg, who first made known the genus

Flight of Butterflies Habrodon to be British. In the summer of 1865 he and the late Mr. Wilson paid me a visit at Dublin, and after leaving

Can you tell us where the yellow butterflies are going ? Ireland, Dr. Schimper accompanied a party to the Highlands of

About ten days since, while chatting with several gentlemen Scotland, on which excursion the Habrodon was discovered

at the Jackson Sulphur Well about caterpillars, one of them regrowing on trees near Killin, whence I have specimens from the

marked that the worm was about, for, says he, the yellow butter. party, which were collected on that occasion.

flies are all going east. Glasniven, Oct. 16

D. MOORE

We thought at first he was telling us a "fish story", but soon became convinced that he knew whereof he spoke, for while we

sat there a great number of bright-coloured, medium-sized butter. Corrections

Aies came by us, all winging their way towards the rising sun. A PARENTHETICAL passage in my "note on the Cycloid” has Now, we do not think that this fly is related to the caterpillar, been transposed. Instead of " (a luminous point for the nonce) for the moth that lays the egg of that destructive worm is a very the sun in the meridian," &c., it should have been “the sun (á different fy; nevertheless it is a singular fact that they are all luminous point for the nonce) in the meridian," &c.

going east. In Mr. Abboti's paper on 1 Argus and its surrounding nebula

I have been at several different points since leaving Jackson, there occurs the statement that I consider an increased or and at every place they fly the same way. Can you tell us decreased distance in space may account for the fluctuations of whither they go? Perhaps if you will ask the question in your the nebula.” I have never suggested such an explanation. widely circulated journal, some naturalist, or somebody over to What I have said is that the fluctuations, is real, would seem to

the eastward, may tell us where they rest.

ALA suggest that the nebula has not those inconceivably vast dimen- Mobile, Sept. 6 sions which would correspond to the vast distance once assigned [A similar fact will be found recorded in our “Notes" re. tu it. My opinion was (and is), not that the nebula is nearer specting the Urania leilus.-Ed.] than it was formerly, but that it is nearer than it was formerly supposed to be. RICHD. A. PROCTOR

Velocity of Sound in Coal
A Universal Atmosphere

This is a very interesting subject, at least to those who have Will you permit me 'to ask Mr. Mattieu Williams how, on anything to do with coal mines. And yet I have not met with his hypothesis, “that the atmosphere is universal, and that each anything that points to it, nor any formula whereby it might be planet attracts to itself an atmosphere in proportion to its mass,” calculated. But perhaps this is a subject to which the attention he accounts for the well-known fact that ihe moon shows no signs of physicists has not been drawn. I have been told that blastof an atmosphere sufficient to produce any indication of refraction ing has been heard at the distance of 150 yards underground, during the occultations of a star?

and I have heard the signals of the colliers, i.e., by hitting the I think Mr. Williams's book deserves far more attention than surface of the coal with one of their tools, at the distance of it has received, so I trust I shall be acquitted of any wish to fifty or sixty yards, and have also heard the shouts of the men at indulge in carping criticism.

JOHN BROWNING the distance of fifteen yards ; but I have never met any person III, Minories, October 10

who could give the velocity, nor seen any book on physics in which

there is anything concerning it. But perhaps it is a very hard The Temperature of the Sun

subject to deal with from the difference of the specific gravity of HAVING been absent from home I have but just seen Mr.

the coals, and also the different temperatures that we meet there.

And it from these different causes it would be hard to find the Ericsson's article on the “ Temperature of the Sun” in real velocity, yet by calculating a velocity that might be rather NATURE, (No. 101, p. 449. All who feel an interest in the theoretical at first, we might by degrees come nearer the truth. subject must be indebted to Mr. Ericsson for the experimen. tal evidence which he has contributed to the investigation,

D. Joseph and for such further light as his ingenuity will doubtless enable

Ty Draw, Pontyfridd, Oct. 5 him to throw upon it ; but few, I think, will be inclined to admit that the reasoning advanced in his recent article justifies in any degree the inferences which he has there drawn.

Prof, Newcomb and Mr. Stone At the outset of the inquiry it does not seem very likely that I am obliged to Mr. Lynn for pointing out that the statement we shall gain much correct knowledge of the condition of the by “ P. S.” was contradicted. I had not been aware of this. solar atmosphere by inquiring what that condition would be if it It never occurred to me to doubt either the authorship or the were replaced by a medium similar to the terrestrial atmosphere, authenticity of the statement. I cannot tell how it chanced that and containing the same quantity of matter for corresponding " W. T. L 's” response escaped my attention. Perhaps I never areas of the spherical surface. If the case were otherwise it saw the January number of the Astronomical Rexrister; or, would be necessary to point out that Mr. Ericsson's numerical perhaps, a variety of other reasons which would not interest your results are vitiated by his omission to consider that the volume of readers.

I

The only point the least interest in the matter (if the matter Light (for the Natural Sciences Tripos 1972, and has any interest at all

) is the fact that Prof. Newcomb did not following years), by Mr. Trotter, Trinity College, on discuss the observations of 1769, as I had believed. I have Tuesdays, Thursdays, and Saturdays, commencing Thursalready admitted this, and withdrawn those expressions of com

day, October 19. On Chemistry, by Mr. Main, St. mendation which I had founded on the strongly.worded letter of John's College, on Mondays, Wednesdays, and Fridays, at Prof. Smyth, so that I am rather at a loss to know what purpose 12, in St. John's College Laboratory, commencing Wed. Mr. Lynn had specially in view when he wrote his letter. thank him, however, as warmly as though I knew what he meant.

nesday, October 18. Attendance on these lectures is Richd. A. PROCTOR

recognised by the University for the certificate required by medical students previous to admission for the first examination for the degree of M.B. Instruction in Prac

tical Chemistry will also be given. On Palæontology SCIENCE AT THE UNIVERSITIES (the Protozoa and Cælenterata), by Mr. Bonney, S.

John's College, on Mondays, Wednesdays, and Fridays, THE

HE following courses of lectures will be delivered at at 9, commencing Wednesday, October 18. On Geology

the University of Oxford in Natural and Physical (for the Natural Sciences Tripos, preliminary matter and Science during the ensuing term:—The Sedleian Pro- | Petrology), by Mr. Bonney, St. John's College, on Tuesdays fessor of Natural Philosophy, the Rev. Bartholomew and Thursdays, at 9, commencing Thursday, October 19. Price, M.A., will deliver a course of Lectures on Light, A course on Physical Geology will be given in the Lent on Tuesdays, Thursdays, and Saturdays, at one o'clock, | Term, and on Stratigraphical Geology in the Easter Term. commencing October 19th, at the Lecture Room, Mu- Papers will be given to questionists every Saturday at 11. seum, Upper Corridor South. The Savilian Professor of On Botany, for the Natural Sciences Tripos, by Mr. Hicks, Astronomy, the Rev. C. Pritchard, M.A., proposes to give Sidney College, Tuesdays, Thursdays, and Saturdays, at II, two courses of lectures during the present term ; the one on beginning on Tuesday, October 31. The lec:ures during Astronomical Instruments, the other on the Lunar Theory. this term will be on Vegetable Morphology. Mr. Hicks The Professor of Experimental Philosophy, R. B. Clifton, will also give examination papers in Botany to candidates M.A., will give a course of Lectures on Experimental for the next Natural Sciences Tripos on Mondays, at Optics, on Wednesdays and Fridays, at twelve o'clock, 1 P.M., beginning October 30. These examinations will commencing October 20, at the Physical Laboratory, be free to those who have attended the botanical lectures University Museum. The Physical Laboratory of the of the last term. On the Elements of Physiology, by the University will be open daily for instruction in Practical Trinity Prælector in Physiology (Dr. M. Foster), MonPhysics, from ten to four o'clock, on and after Thursday, days, Tuesdays, and Wednesdays, at 11 A.Il., commencing October 19. The Linacre Professor of Anatomy and Monday, October 23. A course of Elementary Practical Physiology, G. Rolleston, D.M., will lecture on Circula- Physiology, on Wednesdays and Thursdays, commencing tion and Respiration, on Tuesdays, Fridays, and Satur- Wednesday, October 25, at 2 P.M. days, at one o'clock, commencing October 20, at the Museum. The Professor proposes to form classes for Practical Instruction, as in former terms. Persons who join these classes will come to the lectures on Saturdays

AN EXPLOSION (?) ON THE SUN* at one o'clock, and will also come to the Museum on three mornings in the week for study and demonstration, ON N the 7th of September, between half past 12 and under the superintendence of Mr. Charles Robertson, the

2 P.M., there occurred an outburst of solar energy Demonstrator of Anatomy, and Mr. C. S. Taylor, of remarkable for its suddenness and violence. Just at noon Merton College. The Hope Professor of Zoology, J. o. the writer had been examining with the telespectroscope an Westwood, M.A., will not lecture during the present term, limb of the sun.

enormous protuberance or hydrogen cloud on the eastern being engaged in the classification of the Hope, Burchell, Bell, and other collections, at the New University Mu

It had remained, with very little change since the preseum, where he will be happy to see gentlemen desirous

ceding noon, a long, low, quiet-looking cloud, not very of studying the Articulated Animals, daily, between i and

dense or brilliant, nor in any way remarkable except for 5 P.M. A course of lectures will be given on behalf of horizontal, and floated above the chromosphere, with its

its size. It was made up mostly of filaments nearly the Professor of Chemistry, by A. Vernon Harcourt, M.A., in continuation of the Professor's course, on Tuesdays

lower surface at a height of some 15,000 miles, but was and Saturdays, at eleven o'clock, commencing October connected to it, as is usually the case, by three or four 21, at the Museum. There will also be an Explanatory

vertical columns brighter and more active than the rest. and Catechetical Lecture on Thursdays, at eleven o'clock,

Lockyer compares such masses to a banyan grove. In to commence on Thursday, October 26. The Laboratory

length it measured 3' 45", and in elevation about 2' to its of the University will be open daily for instruction in

upper surface, that is, since at the sun's distance, 1" equals Practical Chemistry from 9 A. M. to 3 P.m., on and after 450 miles, nearly, it was about 100,000 miles long by Monday, October 16. The ordinary course of instruction

54,000 high. in the laboratory includes those methods of Qualitative

At 12.30, when I was called away for a few minutes, Analysis, a knowledge of which is required of candidates

there was no indication of what was about to happen, for honours in the School of Natural Science who make

except that one of the connecting stems at the southern Chemistry their special subject. In addition to this two

extremity of the cloud had grown considerably brighter, courses of instruction will be given in the Laboratory, the and was curiously bent to one side ; and near the base of one on the Methods of Qualitative Analysis, the other a

another at the northern end a little brilliant lump had course of elementary practical instruction in Chemical developed itself, shaped much like a summer thunderManipulation, intended for those commencing the study

head. of Chemistry

What was my surprise, then, on returning in less than At Cambridge the following lectures in Natural Science whole thing had been literally blown to shreds by some

half an hour (at 12.55), to find that in the meantime the will be delivered during Michaelmas Term in connection with Trinity, St. John's, and Sidney Sussex Colleges :

inconceivable uprush from beneath. In place of the quiet On Electricity and Magnetism (for the Natural Sciences filled with flying débris-a mass of detached vertical fusi

cloud I had left, the air, if I may use the expression, was Tripos), by Mr. Trotter, Trinity College, on Mondays, form filaments, each from 10" to 30" long by 2" or 3" wide Wednesdays, and Fridays, at 10, commencing Wednesday, October 18. On General Physics, Sound, and * From the Boston Journal of Chemistry, communicated by the author.

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brighter and closer together where the pillars had formerly found in the crevices of rocks, beneath the bark of trees, stood, and rapidly ascending.

and its aliment not wholly vegetarian, yet such as called When I first looked, some of them had already reached forth no display of boldness in order to procure a sufficient a height of nearly 4' (100,000 miles), and while I watched supply, This peaceful demeanour was observed under the them they rose with a motion almost perceptible to ascendency of Moaic conservatism. The European has the eye, until in ten minutes (1.5) the uppermost were been the means of corrupting the simplicity of its ancient more than 200,000 miles above the solar surface. This habits ; the meat-gallows of the back-country squatters was ascertained by careful measurement; the mean of attracted the attention of our mountain-parrots in the three closely accordant determinations gave 7' 49" as the winter season. To them they became points of interest in extreme altitude attained, and I am particular in the state their wanderings, and furnished many a hearty meal torn ment because, so far as I know, chromospheric matter from the dangling carcass as it swung in the frosty air ; (red hydrogen in this case) has never before been observed neither were the drying sheepskins, stretched on the rails at an altitude exceeding 5'. The velocity of ascent also, of the stockyard, neglected. The Paneka has been destined 166 miles per second, is considerably greater than any- to supply the enterprising Kea with a dainty only equalled thing hitherto recorded.

perhaps by that which the epicurean African cuts warm As the filaments rose they gradually faded away like a from his bovine victim-our educated bird now tears his dissolving cloud, and at 1.15 only a few filmy wisps, with food from the back of the living sheep. From a local some brighter streamers low down near the chromosphere, paper one learns that, for the last three years the sheep remained to mark the place.

belonging to a settler“ in the Wanaka district, (Otago) But in the meanwhile the little “ thunder head," before appeared afflicted with what was thought to be a new kind alluded to, had grown and developed wonderfully into a of disease ; neighbours and shepherds were equally at a mass of rolling and ever-changing flame, to speak accord- loss to account for it, having never seen anything of the ing to appearances. First it was crowded down, as it kind before. The first appearance of this supposed were, along the solar surface ; later it rose almost pyra- disease is a patch of raw flesh on the loin of the sheep, midally 50,000 miles in height; then its summit was about the size of a man's hand; from this matter condrawn out into long filaments and threads which were tinually runs down the side, taking the wool completely most curiously rolled backwards and downwards, like the off the part it touches, and in many cases death is volutes of an Ionic capital : and finally it faded away, the result. At last a shepherd noticed one of the and by 2.30 had vanished like the other.

mountain parrots sticking to a sheep and pecking at The whole phenomenon suggested most forcibly the a sore, and that the animal seemed unable to get rid of its idea of an explosion under the great prominence, acting tormentor. The runholder gave directions to his shepmainly upwards, but also in all directions outwards, and herds to keep watch on the parrots when mustering on then after an interval followed by a corresponding inrush : the high ground; the result has been that during the preand it seems far from impossible that the mysterious sent season when mustering high upon the ranges near coronal streamers, if they turn out to be truly solar, as the snow line, they saw several of the birds surrounding a now seems likely, may find their origin and explanation in sheep which was freshly bleeding from a small wound in such events.

the loin ; on other sheep were noticed places where the Kea The same afternoon a portion of the chromosphere on had begun to attack them, small pieces of wool having the opposite (western) limb of the sun was for several been picked out.” hours in a state of unusual brilliancy and excitement, and From the recent settlement of the country, it would be showed in the spectrum more than 120 bright lines whose quite possible to date each step in the development of the position was determined and catalogued-all that I had destructiveness of the Kea, the gradual yet rapid change ever seen before, and some fifteen or twenty besides. from the mild gentleness of a honey-eater, luxuriating

Whether the fine aurora borealis which succeeded amidst fragrant blossoms when the season was lapped in in the evening was really the earth's response to this mag- sunshine, or picking the berried fruits in the more shel. nificent outburst of the sun is perhaps uncertain, but the tered gullies when winter had sternly crushed and hidden coincidence is at least suggestive, and may easily become the vegetation of its summer haunts. Led, perhaps, to something more, if, as I somewhat confidently expect to relish animal food from its partly insectivorous habits, its learn, the Greenwich magnetic record indicates a disturb- visits to the out-stations show something like the bold ance precisely simultaneous with the solar explosion. thievery of some of the Corvidae, whilst its attacks on

C. A. YOUNG sheep feeding on high ranges exhibit an amount of daring Dartmouth College, September 1871

akin to the savage fierceness of a raptorial. Is the position of Nestor in our avifauna an anomalous one? A

sucker of honey, devourer of fruit, destroyer of insects, THE KEA-PROGRESS OF DEVELOPMENT

render and tearer of flesh-will the difficulty be met by A NOTICE of the development of a striking change classing our mountain bird as omnivorous, or is it to be

in the habits of a bird may be considered by considered as only one other instance in which system naturalists interesting enough to justify a brief record in puzzles and hampers the field naturalist?

Thos. H. POTTS your journal. The Kea (Nestor notabilis) may be seen and heard in certain localities amidst the wild scenery of the Southern Alps in the middle island of New Zealand,

ON A NEW FORM OF CLOUD* for it is not so rare as has been described. This fine bird belongs to one of our indigenous genera, an examination THE raccompanying figure on p. 490, represents a of its structure proves that it shares with the Kaka a claim

of cloud have seen in to a position amongst the Trichoglossina or Brush-tongued my life ; * the first time about the commencement of Parrots; the under side of its thick tongue near the tip is June 1871, at five o'clock in the evening, at Washingfringed with papillæ, enabling it to collect the sweets of its ton, U.S. ; the second at Beloit, Wisconsin, U.S., during favourite blossoms. Through how many years has this the same year, and at the same hour. The state of species been content to range over shrub-covered heights the atmosphere presented similar meteorological conand rock-bound gullies, gathering its subsistence from the ditions at both times. The appearances coincided with nectar of hardy flowers, from the drupes and berries of

See my new classification of clouds with sixteen engravings in the the dwarfed shrubs that contend with a rigorous climate, Rural Neto porker, January 29, February 26, April 9, May 21, June 4 and and press upwards almost to the snow line of our Alpine It will be reprinted in the Report of the Smithsonian Institution for

1870, with an historical introduction, in print now for the next number of the giants? To these food-resources may be added insects | Annales Hydrographiques of Paris,

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a north-west storm passing slowly north of the city facts has been completed. Dr. M‘Nab's article convinces without bursting, and disappearing in the south-east. me, as indeed is necessarily the case, that he has no conGreat branched masses of cloud appeared suspended from ception either of the nature or of the extent of those a sheet of Pallio-Cirrus. Some resembled bunches of facts. Were it otherwise, he would see at a glance how grapes (a), others stalactites (6) in a striking manner, far his explanations are from accounting for them. He and still others formed round balls (c) separated by the has given an exposition of a common process of exo. azure of the sky. These balls seemed to be formed of genous growth, which is true as far as it goes ; but I can snow fiakes, and approached the form of Cirro-Cumu- assure him that the modifications of that process, so far lus; one might say of masses of snow rolled upon as we can infer from peculiarities of structure, have been themselves by the effect of electric currents deve- much more varied in past geological ages than he is aware loped during the storm. This was accompanied by of. He is pleased to affirm two things which require thunder and lightning at Washington, and by lightning proof : (1) that I have been led away by the mere superonly at Beloit. d represents one of these balls de ficial resemblance of the parts ;” and (2) that I have tached, with two sorts of penumbra, darker in e and f, " never tried to understand the homologies of these and a streak at g, the rest whitish. Somebody at Beloit stems.” To the first of these charges I plead not guilty ; told me he had seen this form of cloud two or three to the second I reply that I was trying to understand times. A slightly brilliant aurora borealis was seen at these things when he was a child at school. Whether or Beloit the same evening. The night of its appearance at not I have succeeded remains to be seen, but as yet he Washington no aurora was visible, but I do not know has told me nothing new to me. whether there may not have been one in other parts of In studying the relations of the several parts of a

plant, we have to consider three things, of which Dr.
M‘Nab has mainly dwelt upon one. These are-

1. The relative positions of the tissues.
2. The mode of their development.
3. The functions they have to perform.

66

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The first point where I shall differ from Dr. M‘Nab is in supposing that a correspondence on the first of these clauses invariably pre-supposes a similar correspondence

on the second. I shall have to show on a future occasion the United States. The same evening and the next day that Nature has attained the same end in more ways than at Beloit the temperature fell several degrees. It is a

one ; and that she refuses to be shut up to that dichogeneral belief that the aurora borealis is followed by a

tomous arrangement pre-supposed by Dr. M‘Nab; but decrease of temperature. We know that in higher ticular mode of growth upon which he rests his case.

for the present I will limit my illustration to the parstrata of the air vapour of water floats constantly in the form of frozen needles, especially in the polar regions. It

If we take a perfect Stigmaria, we find its centre (a, Fig. is not impossible that these ice needles may be drifted 2, p. 491) to be occupied by an axis of ordinary cellular paby the electric current which engenders the aurora renchyma unmixed with any vascular tissue. This is surborealis* into lower latitudes, and thence towards

lower rounded by a ligneous or vascular cylinder (6) which, in its strata of the atmosphere by the winds and storms.

turn, is invested by a thick bark (c) consisting of a mixHence the cooling of the air which is said to attend the

ture of parenchyma and prosenchyma arranged in definite ANDRÉ POËY

positions. The central axis differs in no respect whatever from the cellular piths of ordinary exogenous stems. The

woody cylinder consists of vessels which, in the transEXOGENOUS STRUCTURES AMONGST THE

verse section, are arranged in radiating lines (d) running

from the pith to the bark; these lines are separated by STEMS OF THE COAL MEASURES

intervening cellular tracts (e), which I, in common with HE

on the existence of an exogenous process of growth The radiating lines of vessels exhibit proofs of distinct amongst the cryptogamic stems of the coal measures, interruptions to the process of growth, and afford clear confirms my previous conviction that the discussion of evidence that the cylinder began as a thin ring of vessels the details of my proposition can lead to no beneficial surrounding the pith, and which grew, by successive results until the publication of my large store of new

concentric additions of vessels, to its peripheral surface

where the cambium layer is found in ordinary exogens. !* See my Memoir on the Development of Electricity during the Aurora Borealis in the " Annuaire de la Société Météorologique de France," 1861,

We have here no trace of the limiting tissues of which vol. ix. p. 42.

Dr. M‘Nab speaks ; the growth has been free and prac

aurora.

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