work to which I can direct your attention as giving the fauna of a particular district, with the geographical range of such of the species as are likewise found elsewhere. R. M'Lachlan, who in 1865 had published (Trans. Ent. Soc. ser. 3, v.) a Monograph of the British Ca dis-flies, gave in 1868 (Trans. Ent. Soc. for 1868) a Monograph of the British Neuroptera Planipenna, but little is there said of the European range of our species. In 1867 (Entom. Monthly Mag. iii.) Mr. M'Lachlan, who is one of our most philosophical writers, gave a Monograph of the British Psocidæ, and he there says with reference even to their distribution in our own country, 'As a rule, I have not mentioned special localities; these insects have been so little collected that an enumeration here of known or recorded localities would probably appear ridiculous in a few years.' The Rev. T. A. Marshall has given (Entom. Monthly Mag. i. to iii.) an essay towards a knowledge of the British Homoptera, in which occasionally allusion is made to the European distribution of our British species.

"The position of the Insect-fauna of Britain may be thus stated the late J. F. Stephens commenced in 1827 a systematic descriptive work of all the orders of British Insects as 'Il ustrations of British Entomology;' it ceased to appear after 1835, until a supplementary volume came out in 1846. The Lepidoptera, Coleoptera, Orthoptera, Neuroptera were wholly, the Hymenoptera partly, done, the Hemiptera and Diptera altogether left out. In 1839 Mr. Stephens published, in a more compendious form, a Manual of British Beetles.' In 1849 an attempt

was made to supply the gaps in the British Entomology left by Stephens, and a scheme of a series of volumes called Insecta Britannica' was elaborated, in which Mr. F. Walker was to undertake the Diptera, Mr. W. S. Dallas the Hemiptera, and great progress having been made in our knowledge of the smaller moths since 1835, I undertook to write a volume on the Tineina. This scheme was so far carried out, that th ee volumes on the British Diptera by Mr. F. Walker (assisted by the late A. H. Haliday) appeared in 1851, 1852, and 1856, and my volume on the British Tineina in 1854. In 1859 another great group of the smaller moths was described by S. J. Wilkinson in a volume entitled The British Tortrices.' The British Hemiptera, not having been done by Mr. Dallas, were undertaken by Messrs. Douglas and Scott for the Ray Society; and in 1865 a 4'0 volume was issued, containing the Hemiptera, Heteroptera, leaving the Homoptera for a second volume, still in progress. Even in this elaborate work little or nothing is said of the geographical distribution out of Br tain of our British species. The same will apply to the late J. F. Dawson's Geodephaga Britannica," published in 1854; to Westwood's "Butterflies of Great Britain,' pub'ished in 1855; and to E. Newman's 'Illustrated Natural History of British Moths,' published in 1869.

"I believe I do not at all exaggerate if I say that for many years Entomology was pursued in this country with an insularity and a narrow-mindedness of which a botanist can scarecly form a conception. The system of only collecting British Insects was pursued to such an extent, that it was almost a crime to have a non-British insect in one's possession; if accidentally placed in one's cabinet it might depreciate

the value of the entire collection, for Mr. Samuel Stevens can assure you that the value of the specimens depends very much upon their being indubitably and unmistakeably British. A specimen caught in Kent which would fetch 2. would not be worth 25. if caught in Normandy. I satirised this practice several years since in the Entomologists' Weekly Intelligence' (vol. v. and 1858, articles Jeddo' and 'Insularity'), but it is yet far

from extinct "

Perfectly concurring in Mr. Stainton's observations in the last paragraph, I would however add that there are purposes for which a local or geological collection distinct from the general

one may be of great use, and such a collection would be much impaired by the introduction of stray foreign specimens. In a local museum, a separate room devoted exclusively to the productions of the locality is very instructive with reference to the history of that locality, and I have seen several such spoiled by the admission of exotic specimens, giving the visitor false impressions, which it takes time to remove. But it is never from such an exclusive collection that the fauna or flora of the district can be satisfactorily worked out, or that any branch of Zoology or Botany can be successfully taught.

Mr. Stainton adds, "It has been suggested to me that those who have critically studied the distinctions between closely allied species have rarely the time to work out in addition their geographical range, and that those who might work up the latter subject

might fail in their good intentions for want of a proper knowledge of species." Upon this I would observe that, in the due appreciation of a species of its limits and connections, its geographical range and the various forms it assumes in different parts of its area are an essential element; and it appears to me that the neglect of this and other general characters is one reason why many able naturalists, who have devoted their lives to the critical distinction of races of the lowest grades unduly raised to the rank of species, have really contributed so little to any science but that of sorting and naming collections. On the other hand, the study of geographical range without a proper knowledge of species is little more than pure speculation. Division of labour carried too far tends to narrow the mind, and rather to delay than advance the healthy progress of science.

Mr. Stainton informs me that "there has just appeared a monograph of the Ephemeridæ, by the Rev. A. É. Eaton (Trans. Entom. Soc. 1871), treating of those insects throughout the globe; and when any species are noticed which occur in this country, their entire geographical range is noticed. It is altogether a valuable paper, on account of the thoroughness with which it seems to be done."

Since I last noticed our biological publications two valuable and beautifully illustrated but costly Ornithological works, Sclater and Salvin's "Exotic Ornithology," and Sharpe's "Monograph of the Alcedinida," have been completed, and various Memoirs by Flower, Mivart, Parker, and others, have considerably advanced our knowledge of the comparative anatomy of various groups of Mammalia. In our own country also, as well as on the Continent, the biology of various distant lands has continued to be worked out in Memoirs or independent publications, which I had contemplated noticing in succession; but time obliges me now to stop, and defer to a future occasion the compilation of the notes I had collected on North American, Australian, and other Monographs, Faunas, and Floras.

SCIENTIFIC SERIALS

THE Geological Magazine for June (No. 84) commences with some notes on Crinoids by Mr. John Rofe, relating rather to the zoological than to the geological aspects of that class of animals. Mr. Rofe describes some experiments made on recent Crinoids by treating them with solution of potash or muriatic acid, from which he arrives at the conclusion that their hard parts are invested by a membrane giving them a certain degree of flexibility, a general position which few naturalists will be inclined to dispute. But the details of structure described by Mr. Rofe will be found of much inproximation between the Crinoids and the Tunicata, which, to say terest. In his concluding remarks he endeavours to show an ap the least of it, is very doubtful.—Mr. S. Allport publishes a note on the microscopic structure and composition of a rock from the "Wolf Rock" off the Land's End, which he identifies with

phonolite, and justly protests against the system which gives different names to rocks identical in mineral composition because they happen to be of different geological ages.-Mr. D. Mackintosh describes the drifts of the west and south borders of the Lake district, with especial reference to their great granitic dispersions which he believes have taken place; and Messrs. C. and A. Bell discuss the divisions of the English Crags as indicated by their invertebrate fauna. They propose as the result of their investigations, to divide the Crag into Upper, Middle, and Lower; the Upper including the Norwich, and the upper part of the so-called Red Crag; the Middle, the remainder of the Red Crag; and the Lower, the Coralline Crag. The last paper consists of a comparison of the metamorphic rocks of Scotland and Galway, by Mr. G. H. Kinahan. The first and last of these papers are illustrated with plates.

The second part of Tome xliii. of the Bulletin de la Société Impé riales des Naturalistes de Moscou, completing the first half volume for 1870, is the last portion of this publication that has yet reached this country. It contains the continuation of M. Ferd. von Herder's notice of the monopetalous plants collected by G. Radde and others (Plantæ Raddeanæ Monopetala) in Eastern Siberia, the Amurland, Kamtschatka, and Russian America, and includes references to numerous species of Composiæ.-M. N. Erschoff communicates a note upon the Lepidoptera of Western Siberia, containing a list of species from the town of Omsk. - A Russian paper on the Oligochaetal Annelid,

Peloryctes inquilina, by M. H. Zingera, will probably attract few English readers.-M. E. Regel publishes a portion of a second supplement to the enumeration of the plants collected by Sewerzow in 1857 in Central Asia. It includes the Ranunculaceæ, Berberideæ, Nymphæaceæ, Papaveraceæ, Fumariacea, and Cruciferæ. Several new species are described.-Another botanical paper is an abridged French translation of part of the Introduction to a Flora of Moscow, by M. N. Kauffmann, the translation being made by Mr. G. O. Clerc. The Flora, which is a Catalogue of the vascular plants of the Government of Moscow, will appear in future numbers. We find in this number two entomological papers, both on Coleoptera, and one of them of great importance, namely, a Monograph of the Graphi. pteridæ by the Baron Chaudoir. The other paper is a continuation, by M. Victor Motschoulsky, of his apparently interminable enumeration of the new species of Coleoptera collected by him in his journeys. It includes descriptions of species of Melasomata, and is illustrated with two plates.-M. G. Schweizer describes an easy method of approximately finding the meridian line; and M. A. Trautschold gives a short notice of some cretaceous fossils from Ssaratof and Ssimbirsk.

Paleontographica.-Beiträge zur Naturgeschichte der Vorwelt. Herausgegeben von Dr. W. Dunker und Dr. K. A. Zittel. Band xx. Lief 1., 1871. In this part of the well-known and most valuable Palæontographica," Prof. Geinitz commences a monograph of the fossils of the Lower Quader and Lower Pläner beds in the Saxon Elbe valley, which he regards as forming the lowest part of a great Quader-formation, including the Senonian, Turonian, and Cenomanian stages of the French geologists. His Lower Quader is equivalent to the Upper Greensand of English geologists. It is well known that sponges are among the most abundant and striking fossils of our Upper Greensand, and the corresponding beds in the valley of the Elbe seem to be equally rich in remains of this lowest class of animals. With the exception of a summary of the geology of the district, the whole of the present part of Prof. Geinitz's work is occupied by descriptions of sponges, the species of which are beautifully figured in the accompanying plates. Laying the reproaches of Oscar Schmidt to heart, Prof. Geinitz endeavours to arrange his fossil forms in ac. cordance with the system of that author, although, as he justly remarks, it is impossible in the study of fossil sponges to have recourse to those minute characters derived from the spiculæ, which form the basis of recent attempts to classify the recent forms. He notices in all twenty-eight species, of which six appear to be new.

SOCIETIES AND ACADEMIES

LONDON

Royal Society, June 15, "On a Law in Chemical Dynamics." By John Hall Gladstone, F.R.S., and Alfred Tribe.

It is well known that one metal has the power of decomposing the salts of certain other metals, and that the chemical change will proceed until the more powerful metal has entirely taken the place of the other. The authors have investigated what takes place during the process.

The experiments were generally performed as follows:-72 cubic centimetres of an aqueous solution of the salt of known strength, and at 12° Centigrade, were placed in a tall glass; a perfectly clean plate of metal of 3,230 square millimetres was weighed and placed vertically in this solution without reaching either to the top or bottom; the action was allowed to proceed quietly for ten minutes, when the plate was removed, and the deposited metal was washed off. The loss of weight gave the amount of metal dissolved, and represented the chemical action. The most complete series of results was with copper and nitrate of silver.

In the earlier terms of this series, twice the percentage of silver salt gives three times the chemical action. The close agreement of the observed numbers with those calculated on this supposition continues as far as the 9th term. The law then breaks down, and after about 7 per cent. the increased action is almost in direct ratio with the increased strength.

The position of the plate in the solution was found to make no difference to this 2-3 law.

Similar series of experiments were made with zinc and chloride of copper, zinc and sulphate of copper, zinc and nitrate of lead, iron and sulphate of copper, and other combinations; and in every instance where the solution was weak and the action

simple, the law of three times the chemical change for twice the strength was found to hold good.

It was proved that the breaking down of the law at about 35 per cent. of salt in solution was irrespective of the quantity of the liquid, or of the time for which the plate was exposed, With 72 cub. centims. of a 1'41 per cent. solution of nitrate of silver, the rate of action remained sensibly the same for as long as twenty-five minutes, notwithstanding the constant deposition of silver. This apparently paradoxical result is due to fresh relays of the original solution being brought up to the plate by the currents produced, and that period of time elapsing before any of the products of decomposition are brought back again in their circuit.

When it was perceived that within easily ascertainable limits the chemical action is the same for similar consecutive periods of time, experiments were made in far weaker solutions. It was only necessary to lengthen the time of exposure. It was thus found that the law of three times the chemical action for twice the strength of solution holds good through at least eleven terms of the powers of 2; in fact, from a solution that could dissolve one gramme of copper during the hour, to a solution that dissolved only o'000001 gramme, a million times less.

At

The manner in which the silver is deposited on a copper plate was examined, and the currents produced were studied. first a light blue current is perceived flowing upwards from the surface of the plate, presently a deep blue current pours downwards, and these two currents in opposite directions continue to form simultaneously. A similar phenomenon was observed in every case where a metallic salt attacked a plate of another metal. The downward current was found to be a solution of almost pure nitrate of copper, containing about three times as much NO, as the original silver solution, while the upward current was a diluted solution of the mixed nitrates. Moreover, the heavy current took its rise in the entangled mass of crystals right against the plate, while the light current flowed from the tops of the crystalline branches. It was evident that when the fresh silver was deposited on these branches, and the fresh copper taken up from the plate, there was not merely a transference of the nitric element from one combination to another, but an actual molecular movement of it towards the copper plate, producing an accumulation of nitrate of copper there, and a corresponding loss of salt in the liquid that is drawn within the influence of the branching crystals. Hence the opposite

currents.

The amount of action in a circuit of two metais and a saline solution must have as one of its regulating conditions the conducting-power of that solution. It appeared by experiment that a strong solution of nitrate of silver offers less resistance than a weak one; and it was also found, on adding nitrate of potassium to the nitrate of silver, that its power of attacking the copper plate was increased; that the augmentation of the foreign salt increased the action still further; and that the 2-3 law holds good between two solutions in which both the silver and potassium salt are doubled, though it does not hold good if the quantity of Similar results were obtained foreign salt be kept constant. with mixed nitrates of silver and copper.

While these later experiments offer an explanation of the fact that a solution of double the strength produces more than double the chemical action, they do not explain why it should produce exactly three times the effect, or why the ratio should be the same in all substitutions of this nature hitherto applied. The simplicity and wide range of the 2-3 law seems to indicate that it is a very primary one in chemical dynamics.

"On Cyclides and Sphero-Quartics." By John Casey, LL.D.

Royal Institution of Great Britain, July 3.-Sir Henry Holland, Bart., M.D., F.R. S., president, in the chair. William Amhurst Tyssen Amhurst and Lawrence Trent Cave were elected members.

Royal Geographical Society, June 26.-Major-General Sir Henry C. Rawlinson, K.C.B., president, in the chair. The following new fellows were elected: Thomas Brassey, M.P.; T. B. Baker, C. B.; D. Chinery (Consul-General for Liberia); Commander C. D. Inglis, R. N.; William Charles Jackson; G. W. Kennion; Alfred Morrison, Wilham G. Margetts, Colonel R. Maclagen, R. E.; Captain G. S. Nares, R.N.; and James Rickards. A letter was read from Sir Roderick Murchison, giving Dr. Kirk's views of Dr. Livingstone's position, as communicated in a recent letter from Zanzibar, dated the 30th April last. It appeared that

no one at Zanzibar had been to Manime, the place where Living stone was last heard of; bat Dr. Kirk had ascertained that it was about a month's journey (200 or 300 miles) west of Lake Tanganyika, and was a thriving ivory-mart. Dr. Kirk expressed his hopes that, if Livingstone should have settled the problem of the outflow of Tanganyika, he would be satisfied, and leave all the rest of the work to future travellers, seeing that he has been out upwards of five years, and must sorely want rest. Abundant supplies were awaiting the great traveller's orders at Ujiji, on the shores of the lake.-Letters were read from Dr. J. D. Hooker to Sir Roderick Murchison, giving a description of his recent ascent of the Atlas Mountains, at two points south-west of the city of Marocco. On the first attempt, Dr. Hooker's party ascended to 12,000 feet; and on the second to the summit of a peak, further westward, 11,500 feet high. Storms of snow and hail were encountered near the crests; but the snow seemed to lie more compactly, and to a lower level (7,000 feet) further east. Constant humid and cold winds from the north are the cause of the low temperature, in consequence of which northern species of plants are found on the Atlas, to the exclusion of southern types.-A paper was read by Captain A. F. P. Harcourt on the districts of Kooloo, Lahoul, and Spiti, in Northern India; and a second one, by Major Sladen, on an exploration between the Irrawady and south-western China. Sir Donald MacLeod (late governor of the Punjaub), Sir Arthur Phayre, General Fytche (Commissioner of British Burmah), Colonel H. Yule, Mr. T. T. Cooper, Sir John Bowring, and others took part in the discussion, which followed the reading of the two papers.-The President announced that the Council had renewed, for the year 1872, the offer of geological prize medals to the chief public schools; and that the special subject for the year, both in the physical and the political divisions, would be South America. A proposition from the president for a vote of thanks to the Chancellor and Senate of the London University, for the use of their great hall, met with unanimous approval. The president stated that, although the ordinary meetings of the session had terminated, it was likely that a special sitting would be held to receive the Emperor of Brazil, an honorary member of the Society, should his Majesty accept, on his arrival, the invitation the Council had forwarded.

Anthropological Institute, June 19.-Sir John Lubbock, Bart., president, in the chair. Mr. G. Latimer was elected a local secretary for Puerto Rico and Logan; Dr. D. H. Russell

was

elected a local secretary for Bonny, west coast of Africa.-Prof. Busk exhibited two human jaws of remarkable thickness found in the superficial deposit of a cave near Sarawak, Borneo. Mr. Josiah Harris exhibited from Macabi Island, off the coast of Peru, wood carvings, pottery, and cotton rags. The rags extended many hundred yards at an average thickness of five feet, and below a deposit of several feet of guano. The wood and pottery were discovered at a depth in the guano of from fifteen to forty-five feet.-Mr. G. M. Atkinson communicated some interesting facts connected with the discovery of a kitchen-midden in Cork harbour.-Mr. H. W. Flower exhibited a large jade implement from New Zealand.-A paper by Mr. A McDonald was then read, "On the Mode of Preserving the Dead among the Natives of Queensland."-Dr. Sinclair Holden contributed a paper On Forms of Ancient Interments in Antrim ;" and Mr. Hodden M. Westropp read a paper "On Analogies and Coincidences among Unconnected Nations."

DUBLIN

Royal Irish Academy, April 24.-The Rev. J. H. Jellett, president, in the chair. Mr. R. C. Tichbourne read a report on the molecular dissociation by heat of compounds in solution. The Rev. Dr. W. Reeves read a paper on the Irish tract by Onegus the Culdee, on the mothers of the saints of Ireland. PARIS

Académie Française. This is the most ancient of the French Academies, its special object being the publication of a Dictionary of the French language, which is thus officially protected against innovations. No word is considered classical without being duly registered in the Dictionary of the French Academy. Several editions have appeared successively, each of them containing many alterations. The next edition will soon be published, and is just now in active preparation. On June 29 the French Academy elected its Perpetual Secretary. All the votes were taken by M. Patin, a member of the Institute for the last twenty-eight years, and Professor of Greek Literature at the Sorbonne. The principal work of M. Patin is a study of

the Greek tragedians, which is highly csteemel in France and abroad. The late Perpetual Secretary was the celebrated M. Villemain, a great friend of M. Guizot, and a former Minister of State in Louis Philippe's time. The election of M. Patin, although undisputed, was an event in the academical world, and many members left their residences, and even foreign lands, to vote for him. Amongst these learned travellers we must notice Father Gratry, of London, and the Marquis de Noailles, Frenci Ambassador in London. MM. Guizot, Octave Feuillet, Nisard, &c., were present.

Académie des Inscriptions et Belles Lettres. - This Academy has also been engaged in filling the vacancies death had created in its ranks. M. Villemain was an ordinary member of this Academy. A scrutiny took place on the 30th ult., for the election of his successor. M. Charles Thurot was nominated by twenty-three votes against very few given to four other candidates. The Academy had also to vote for a successor to M. Alexandre, an inspector of the Academy, who was known merely by the publication of a Greek dictionary, which is the most useful in grammar schools. The succession to this office was more vigorously contested. M. de Rozière was elected only after a scrutiny, since a candidate must receive the actual majority of votes. A corre spondent was also appointed. The successful candidate was M. Amari, an Italian learned antiquary of universal celebrity. these nominations will be submitted to M. Thiers for approval, but it is a mere formality, and the assent of the Executive has never been refused for more than thirty years. M. Thiers himself is a member of the Institute, belonging to the Académie Française.

All

IT

THURSDAY, JULY 13, 1871

THE NEXT TOTAL SOLAR ECLIPSE

T is infinitely to the credit of English men of science that they are at the present moment busily engaged in making arrangements for observations of the Total Solar Eclipse in December next, and it is extremely fortunate for the advance of Science that this rare phenomenonrare, that is, so far as the chance of observing it with moderate facility goes-occurs again just as the knowledge gleaned by the recent expeditions is being garnered to serve as a starting point for future inquiry.

When we state that the eclipse will be visible as a total one in India, Ceylon, and Australia, it may at first be imagined that in this case the facilities are not so very great. This would be quite true if it were necessary to garrison all these stations with observers from England; but, as it happens, the Governments both of India and Victoria have under their orders government astronomers -Mr. Pogson at Madras, and Mr. Ellery at Melbourne ; and all that is necessary is to forward to those stations instructions, so that the observers there may glean all the experience gained in the last eclipse, and instruments such as are required to advance our present knowledge. And here we may remark that our knowledge in solar matters has recently advanced so rapidly, that astronomers have, as it were, to use new weapons in each attack, as artillery gives place to small arms, and small arms to the bayonet, in less scientific warfare.

That India and Australia will thus be provided with everything that may be necessary will be evident when we state that the Astronomer Royal is superintending the adaptation of instruments already in his possession for use in the former country, while the President of the Royal Society has already communicated with the authorities in Australia, offering to aid in every way in the proposed observations-an offer which we doubt not will be accepted, and in both cases we may hope for results of the highest importance, if the local observers set to work with a will. As to the entire sympathy of both governments there can be no question, India was magnificently helpful to Janssen in 1868, and Australia has her spurs to win; and there are good men in plenty, in both places, in whom the Governments may place their fullest confidence.

There remains, then, Ceylon. Both the Royal and Royal Astronomical Societies have determined, if the Government will help, to send out a small party of observers from England to garrison this mid-station, which modern helps to travel have placed at our doors, and who knows that at one station or other Americans and Frenchmen may not be found to join in the good work? The new railway has made an American Expedition extremely easy.

And now let us enter a little more into particulars. The central line of the eclipse will first meet the earth's surface in the Arabian Sea, and entering on the western coast of India, will pass right across one of the most important parts of Hindustan, in a S.E. by E. direction. In this part of the peninsula the sun will be about 20° above the horizon when totally obscured. The duration of totality

VOL. IV.

will be two minutes and a quarter, and the breadth of the shadow about seventy miles. On leaving the eastern coast of the Madras Presidency, the central line will cross Palk's Straits, passing about ten miles S.W. of the island Jaffnapatam, and over the northern part of Ceylon, where the small towns of Moeletivoe and Kokelay will lie near the central line; and alsɔ the well-known naval station of Trincomalee, which will be about fifteen miles S.W. of the line. Continuing its course over the Bay of Bengal, the shadow will cross the S.E. point of Sumatra, and will touch the south-western coast of Java, where Batavia, the capital, will lie nearly sixty miles N.E. of the central line; and two other smaller towns, Chidamar and Nagara, will also be very near the middle of the shadow path. In the Admiralty Gulf, on the N.W. coast of Australia, the eclipsed sun will be only ten degrees past the meridian, and not far from the zenith; in consequence of which the totality will last 4m 18s, or only four seconds less than the time of greatest duration. Lastly, passing through the most barren and uninhabited portion of Australia, crossing the Gulf of Carpentaria and the York Peninsula, the shadow will ultimately leave the earth's surface in the Pacific Ocean.

At present not too much is known about the chances of weather at any place; but what is known seems to point to a fair chance of success in both India and Ceylon, as the eclipse occurs during the N. E. monsoon; but, in any . case, the experiences of the last Expedition show that for such a momentary phenomenon these chances need scarcely be taken too seriously into consideration, seeing that where the finest weather was predicted a terrible pall of cloud covered the sky.

Next as to the work which the present state of our knowledge shows to be most desirable. This has been pointed out by Mr. Lockyer, in a communication to the Royal Society, and here we may in the main quote from his paper. Mr. Lockyer states:

66

In my opinion the fundamental points of attack are : "a. Spectroscopic observations made with such an instrument as the one I took out to Sicily, equatorially mounted, and with reference spectra. "B. Photographic observations made with such an instrument as the one I took out to Sicily, namely, a camera with large aperture and small focal length equatorially mounted. . .

"Perhaps I may clear the ground by stating what, in my opinion is comparatively UNIMPORTANT, so far as the crucial points are concerned, though to be tolerated if the crucial points are strongly taken up.

"y. Polariscopic observations.

"8 Observing Baily's Beads.

There should be one instrument, and Mr. Pogson could probably provide this in India, to determine the position of prominences before and after totality. During totality they should not be observed at all except incidentally.

"At each place (ie., India, Ceylon, Australia) the spectroscopes should be employed for half an hour (to be on the safe side) before totality, in scrutinising the crescent at its narrowest place and the chromosphere outside the following limb of the moon.

"At each place, as before defined, there should be a spectroscope with a finder, and equatorial motion

M

(or some equivalent arrangement) directed to the sun's centre, to record any changes which take place in the spectrum from, say, half an hour before to half an hour after totality, and during totality, bien entendu. The relative darkness or brightness of the lines should be recorded every ten seconds.

TYNDALL'S "HOURS OF EXERCISE IN THE ALPS"

Hours of Exercise in the Alps. By John Tyndall, LL.D., F.R.S. (London: Longmans.)

"To come to the details of the expedition to Ceylon; I am of opinion that it need not exceed the following numbers, as my Sicilian experience has taught me that we may depend upon much valuable help from the officers at the place of observation :

"I Telescope-Spectroscopic observer; 2 assis

tants.

"I Photographer; 2 assistants. This duty perhaps may be entrusted to skilled Sappers.

I Spectroscopic observer; 1 assistant, or 8 in all. "Among general observations, I would point out as being of extreme importance:

"a. Rays before, during, and after totality-their length, direction, and colour.

"B. Colours of the various layers of chromosphere, and of clouds and landscape. The order of these colours is of great importance.

"y. Dark rays or rifts; whether they change, and whether they extend to the dark moon, or stop short above the denser layers of the chromosphere. "8. The colours of the corona between bright or dark rays.

e. All changes in corona.

"J. Comparative brightness of rays and chromosphere and outer corona.

"In the above letter the nomenclature employed is the one I suggested in a recent lecture at the Royal Institution, namely:

"Corona, embracing the whole compound phenomenon outside the prominences (including rays and streamers), part of which is undoubtedly non-solar. "Chromosphere, embracing the whole of the solar portion of corona, and all bright line regions outside the photosphere."

It is scarcely necessary to point out that the above deals with possibilities, rather than with desirabilities. We are convinced that a much larger party would do good work in Ceylon, but our scientific leaders are right in asking what our Government cannot refuse; and, moreover, we may hope that the magnificent stations in India on the Neilgherries, at considerable elevations, will be strongly garrisoned, as they can well be by the eminent observers now in India.

We trust that these efforts to procure fresh observations will meet with the largest measure of success, for certainly the question of the Sun's Corona is the scientific question of the day. Once settle what is the real nature of the sun's surroundings, and the path of work is open for the more distant stars. So long as our knowledge of the sun is clouded by contending hypotheses, we cannot hope for re al progress.

For our part we do not doubt that the Government will act as admirably as they did last year in the same branch of research when the requirements of Science are properly laid before them; and if the elements are equally kind, we may hope for a large increase of our knowledge.

HIS volume is a collection of short articles which have already seen the light in various publications, and are here thrown together, as the author says, "partly to preserve to myself the memory of strong and joyous hours, and partly for the pleasure of those who find exhilaration in descriptions associated with mountain life.” Accordingly we find in it accounts of exciting scrambles, such as the Lawinenthor and the Old Weissthor, the first ascent of the Weisshorn, and the various assaults upon the Of sadder Matterhorn, crowned at last with success. interest are the story of the death of Benner, the professor's faithful guide, upon the Haut de Cry, contributed by one of the survivors; notices of the accidents on the Col de Géant and on the Matterhorn; and, hardly less in interest though with happier ending, the rescue of a porter from the jaws of a crevasse on the great Aletsch Glacier, and the author's own hairbreadth escape on the Piz Morteratsch. All these are described with his usual graphic power and intense appreciation of natural scenery; sometimes in the philosophic vein, when a glass of whisky gives "a flash of energy," and even a ham sandwich can only be regarded as a conditioned form of potential muscular force; or sometimes in the more jubilant mood, when we are shown the grave professor "delighting to roll himself in a bubbling pool in some mountain stream, and afterwards dance himself dry in the sunshine."

Together with these sunny memories of alps and cascades, snow-fields and glaciers, there are some chapters of a more distinct scientific import, to which, as most germane to the pages of NATURE, we shall confine our notice. The first of these the twentieth in the volume-is on Alpine Sculpture. The professor, we need hardly say, is a strong "Erosionist," attributing the valleys to the sculpturing influences of water, frost, and ice, as opposed to those who regard them as the result of fissures in the earth's crust produced by strains during its upheaval. His summary of the evidence for "sculpture v. fracture" strikes us as particularly good, and, as it happens, we can bear testimony from personal experience to the accuracy of the facts cited. He shows that by a simple geometric calculation, the width of the fissures produced by the upheaval of a hundred miles of the earth's crust to a maximum height of four miles would bear a very small ratio to the width of the existing valleys; therefore that the most which can be claimed for fissures is that they have guided the action of meteoric forces, have, as it were, drawn the rough sketch on the stone which has directed the picks of Nature's quarrymen, and guided the chisels of her sculptors. He points out that in the most fissure-like of gorges, such as those of the Via Mala or Pfäffers, characteristic water-marks are visible from top to bottom. His description of the latter may be taken as a summary of the evidence in these and many other cases which he has quoted. "Here the traveller passes along the side of the chasm, midway between top and bottom. Whichever way he looks, backwards or forwards, upwards or downwards, towards the sky or towards the river, he meets everywhere the irresistible and impressive evidence that this wonderful fissure has been sawn through the mountain by the