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Dr. Neumayer quotes Bellinghausen's valuable journal for March 12, 13, and 14, 1820, from which it appears that at least as far south as 61° S. lat., under the meridian of 735° E. long., the sea is free from ice. Besides, it appears from his description that both in the sea and in the sky exists an active animal life, and the coruscation of the sea was observed for the first time by him in high latitudes. The occurrence of this phenomenon proves the existence of a very large quantity of organic remains which have been carried in this direction —a fact which, in conjunction with the other phenomena, Dr. Neumayer thinks has a positively demonstrative

force.

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The first group of most southerly points refers to the regions west of Graham's Land, which according to Dr. Neumayer's theory, is rendered milder so far as climate is concerned, by one arm of the South American current; the second group contains the results of attempts to the east of Graham's Land, and the third, of the journeys of Ross to Victoria Land. Thus then, where the warm currents run towards the south, it is possible to penetrate farthest, and where also, in the regions around the polar circle the girdle of pack-ice is broken through, an open sea is seen in the high south, such as has been described by Ross and Weddell.

With regard to the regions where it is possible to cruise through great stretches inside the polar circle, we find that the most considerable stretch has been navigated between the meridian 30° W. and 50° E. long., where Bellinghausen, Biscoe, and to some extent also Moore, have shown satisfactorily that the land could nowhere extend much farther north than 70°. Also between 70° and 160° W. long. has a large part of the region inside the polar circle been sailed through, and it may with tolerable confidence be surmised that no land of any extent exists there, and that what land there is can extend northwards only a little beyond 70°. From the researches of Ross we learn that from 160° W. and 160 E. long. to far beyond the 70th parallel of latitude no land of any extent exists, while the Americans inform us of a great continent in the neighbourhood of the polar circle between 155° and 95° E. long. Whether this refers only to several island groups connected by ice, or to an actual coast of great extent, cannot, in the present condition of research, be decided.

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According to these numbers, the place where the least advance has been made towards the Pole, between 60° and 90° E. long., is the very part where the condition of the current would prove favourable to a voyage southwards. The question now forces itself upon us, what may be the reason for this, and whether a determined attempt under the meridian of Kerguelen would not lead to the penetration of the polar circle? Leaving out of sight Morrell's doubtful voyages, we see from the following the farthest distance reached at the place in question :

Bellinghausen's highest S. lat. 63° in March 1820
Biscoe's
Kemp's
Moore's

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62.2 63'5 64'3

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1831 1833-3 1845

With the exception of Kemp, all these made their way into the region in question in the direction of the parallel of latitude. Other voyagers until late in the season have frequented that part of the Indian Ocean, some even to the end of March. It is therefore evident, from the narratives of these voyagers, that, according to Dr. Neumayer's notion, no attempt has yet been made in the direction most highly favourable.

It should be especially noted here that, south of the 60th parallel of latitude, in the Austral summer, easterly and south-easterly winds prevail, which, towards the end of the season, frequently blow severe storms. It is, therefore, advisable to search the region to be explored from east to west, in order to find out the most direct possible course towards the south, in order to cut through in the shortest possible time the pack-ice, of the position of which in these regions we have got no idea.

Interesting is the course (says Dr. Neumayer) of the two isothermal lines of o° (the freezing point of the air) for January, February, and for July, August. The isothermal line for the Austral summer assumes the figure of an ellipse, whose smaller axis falls nearly in the direction of the meridian, passing through Graham Land and Sabrina Land from 60° W. to 130° E. long. ; the greater axis goes through 20° E., 160° W. long., in the latter case through Victoria Land, which stretches far towards the Pole, and, in the former through a stretch of the Antarctic Sea, which is discovered as far as to 70°, and in which land has been conjectured to exist, but has not been seen, and according to Morrell, will not be found. Does not the bending towards the equator show the completely oceanic character of the greater axis? The limiting bend of this isothermal for the extreme seasons in the direction of the greater axis, and also the greater bend near the small axis, are unfavourable to the assumption of great stretches of land between Enderby and Graham Lands. With this consideration is connected the further question, whether the fact that the bending towards the equator is considerably less in the Pacific than in the Atlantic Ocean is not to be explained by the existence of Victoria Land, to which there is no equivalent on the opposite side. The

consequence of such a conclusion would be that Enderby Land and Kemp's Land, in whose neighbourhood it has already been assumed that no considerable land would be found, would be islands, and that between Kemp's Land and Termination Land chances of penetrating towards the south would be greater than under the meridian of New Zealand.

Dr. Neumayer appends the following sketch of the plan upon which he thinks any South Polar expedition should be conducted :

1. A wooden sailing-vessel with auxiliary screw of at most 300 tons, thoroughly strengthened at the bow and properly arranged on the upper deck, should be sent out on such an expedition. 2. The ship should be equipped with all the most approved appointments and the most recent and best scientific apparatus suitable for the observation of phenomena of all kinds. 3 Men eminent in each of the principal branches of science should be chosen to accompany the ship, which should first make for the Cape of Good Hope, where all the necessary scientific arrangements and testing of instruments could be made. The Cape, indeed, might be considered as the real starting point of the expedition. 4. For the purpose of regular observations, soundings, and so forth, the expedition should set out about the beginning of the year from the Cape for the various groups of islands visited by Cook and Ross, making for Christmas Haven in Kerguelen, overhauling the observations which have been arranged for now thirty years, and attempting to fix the geographical position of as many points as possible. 5. On the Macdonald Islands, as they stretch farther to the south in this quarter (53° 55′ S. lat., 73° 17'2' E. long.), a depôt should be established, the chief purpose of which should be to maintain an ample stock of coals for the use of the expedition, to convey which from the Cape a transport vessel would be useful. Besides a strongly-built astronomical magnetic observatory should be erected here, which would serve as a basis of observation for the operations of the expedition in the south; for these islands are the outmost fore-posts of the Antarctic regions. 6. The ship could carry on its soundings and researches into the currents, the ocean-bed, &c., with diligence, and go as far south as the season would permit without danger. In December the attempt should be made to cross the polar circle, to force through the girdle of pack-ice, and begin research in the polar regions proper. 7. An attempt should be made, with all energy and circumspection, to winter inside the polar circle, when possibly a suitable harbour might be found on Kemp or Enderby Land. By this means the data for the winter climatology of the Antarctic regions would be ascertained, for which Science has sighed so long. On this position of observation a small contingent of eight or ten men and a whaling-boat should be left, furnished with every means for the preservation of their health and the furthering of scientific knowledge. After establishing this station, the ship itself should return to the Macdonald Islands, and pass the winter, as far the season will permit, in pursuing scientific labours. 8. By the approach of the favourable season in September and October the work could be again transferred to the sea, and particularly a thorough survey of the Macdonald group should be made. In December the ship would again make for

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the south, take up the observers on Kemp's Land, and then proceed to further researches until the end of the favourable season urges a return to the Macdonald Islands. 9. At the conclusion of its work the expedition. could sail for Melbourne, where the necessary arrange10. During ment of the observations could be made. the sojourn of the expedition in and around the Macdonald group, it might be arranged that a series of Australian-bound ships of all nations should from time to time sail southward and visit the island, which, during the Austral summer would be a matter of little difficulty. In this way a regular connection with Europe would be maintained, and intelligence could, now that we have telegraphic communication between Melbourne and England, reach Europe from the Macdonald Islands in from fourteen to eighteen days. Should the latter group, contrary to all expectation, prove unsuitable to a long stay, then must Christmas Haven in Kerguelen (48 41' 1" S. lat. and 69° 3′ 35" E. long.) be chosen for the purpose. Should an expedition be fitted out in connection with that for the observation of the Transit of Venus, the above plan would require to be materially modified.

Dr. Neumayer concludes with some sensible remarks on the qualifications necessary to form an efficient leader of an expedition such as he proposes; the man selected for the purpose must be both a seaman and a man of science, and no mere dilettante discoverer. Should such an expedition ever be organised, the importance of these considerations cannot be overrated.

FAYRER'S THANATOPHIDIA OF INDIA. The Thanatophidia of India. Being a description of the Venomous Snakes of the Indian Peninsula, with an account of the Influence of their Poison on Life; and a series of experiments. By J. Fayrer, M.D., &c. 1 vol. folio, coloured plates. (London: Churchill, 1872.) THIS

HIS is a handsome work, got up in good style, printed

in large clear type, and illustrated with a number of highly-coloured plates. It is intended to supply a want which the author has often heard expressed-" that of reliable information on the venomous snakes of India."

Dr. Fayrer divides his subject into several sections, the first relating to the zoological and anatomical character of the venomous serpents of India, the others treating of the statistics of deaths caused by their bites, of the mode of treatment of such cases, and of numerous experiments undertaken by the author with a view of ascertaining the influence of snake-poisons, and the value of certain reputed antidotes. On cach of these subjects we will make a few remarks.

As regards the more strictly scientific portion of the volume, Dr. Fayrer informs us candidly that we are not to expect anything original. "The classification and definitions are chiefly taken from, or based on, Günther, or other authors of repute, the anatomical descriptions from Owen and Huxley; and to those authorities I make my acknowledgments for much valuable information, remarking, at the same time, that I have carefully verified their descriptions by comparison with, and by dissections of, the snakes themselves." In this passage we think that it is not made sufficiently clear that the whole of the first section of Dr. Fayrer's work is based upon Dr. Günther's

"Reptiles of British India.”—in fact, the classification and descriptions are mostly copied literally therefrom. It is quite true that Dr. Günther's name is frequently introduced, and that frequent passages borrowed from his work are quoted in inverted commas; but, even under these circumstances, we fail to see that Dr. Fayrer is quite justified in appropriating so largely the results of another author's labours to his own use. It would have been easy to state at once that so far as arrangement and classification went, he simply intended to follow those given in "The Reptiles of British India," and to refer his readers to that work for information on these subjects.

In the second section of his work, Dr. Fayrer gives details as to the actual number of deaths caused by snake-bites in India. These statistics were principally obtained from replies to letters on the subject addressed by him to the secretaries and political agents of the several governments. The result arrived at is that the total number of deaths recorded in 1869 in Bengal, the North West Provinces, Oude, and certain other parts of India, embracing altogether a population of about 120,000,000, was 11,416. This total, however, large as it is, Dr. Fayrer fears cannot be regarded as the real mortality in these provinces, the information upon which it is based having been partial and imperfect. Were accurate statistics obtainable from the whole of Hindostan, Dr. Fayrer believes that it would be found that more than 20,000 people die annually in that country from the bites of poisonous snakes. Such being the case, there can be no question as to the importance of the subject discussed in the work before us.

In his third section Dr. Fayrer speaks of the treatment of snake-bite, concerning which, after a certain amount of discussion, he does not appear to have arrived at any very novel results. Ligatures, scarifications, liquor ammoniæ, and hot spirits and water, are the remedies in vogue on such occasions, and to these Dr. Fayrer gives in his adhesion. "The antidotes in addition," he remarks, “may be used by those who have faith in them; but I fear that there is reason to believe that they are of no use." These antidotes, we should have explained, comprehend snakestones, arsenic, bromine, ipecacuanha, senega, and, "indeed nearly every drag in or out of the pharmacopœia."

Numerous reports of cases of snake-bite by medical officers of the Indian Service constitute the fourth section of Dr. Fayrer's work. These have been selected in order to give a fair idea of the symptoms and of the duration of life after the reception of the bite, and of the pathological appearances after the death of the sufferer.

In the concluding portion of the volume, Dr. Fayrer gives an account of numerous experiments undertaken with a view to ascertain the influence of snake-poison on the lower animals, and the value of certain modes of treatment. These experiments were commenced in October 1867, and continued during a period of three years, the object having been to determine the effect of the bite of venomous serpents by actual observation, and to test the value of supposed remedies both internal and external. The snakes with which the experiments were performed were the Cobra, the Ophiophagus or Hamadryad, and the two Indian species of the genus Bungarlus, belonging to the Elapidæ, some of the sea-snakes of family Hydrophiida, the Daboia russellii, and the Echis carinata, belonging to

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the Viperidæ, and one species of Trimeresurus, belonging to the Crotalidæ, or Pit vipers. Of these Dr. Fayrer concludes that as regards deadliness the Cobra, Ophiophagus, and Daboia are very nearly on a par. 'They are quite capable of destroying a full-grown dog in half an hour, sometimes in much less time; and frequently," Dr. Fayrer believes, "man has succumbed within an equally short period, though generally the time is much longer." The Bungarlus cæruleus is believed to be just as deadly as the above-named, but not to kill quite so quickly. The Bungarlus fasciatus is less fatal. The Echis is also very deadly, but from its small size less likely to be fatal to man. Of the sea-snakes much less is known, but it appears that hunan life would be in great danger from their bite. The Elapine snakes of the genus Callophis and the Pit-vipers of Hindostan, although capable of giving a painful and even a dangerous bite, are not nearly so deadly.

The symptoms produced by the bite of these different serpents vary slightly, but not so as to present any great physiological or pathological divergences. All alike point to "exhaustion and paralysis of the nerve-centres," every function falling rapidly, and life becoming quickly extinct. "The post-mortem appearances frequently reveal nothing except the marks of the fangs, or, if the creature has survived some hours, infiltration and perhaps incipient decomposition of the intestines." Warm-blooded animals are acted upon much more vigorously by snake-poison than cold-blooded animals. As regards the latter, poisonous snakes are not, according to Dr. Fayrer's experience, affected by their own poisons, or by that of one of their own species, although the less-poisonous seem to be subject to the venom of their more poisonous relatives. Lastly, although the blood of an animal killed by snakepoisoning destroys life if injected into another animal, there can be no doubt that the body of such an animal may be eaten with impunity. The fowls and pigeons killed in Dr. Fayrer's experiments were always eaten by the natives without any evil consequences following.

Such are some of the results arrived at from Dr. Fayrer's long and laborious series of experiments. We cannot say that there is any great novelty amongst them. As regards the treatment of snake-bite, indeed, it seems quite conclusively proved that the antidotes, commonly so called, are useless, and that it is hardly probable that any direct specific will ever be discovered. Cure failing, the large mortality now due to snake-bite can, therefore, only be materially diminished by prevention; and the simplest mode of prevention - slow as it may be―is, we think, that recommended by Dr. Fayrer in his circular of January 1870*, i.e. to offer small rewards for the destruction of the serpents. The sum expended in this way would, as Dr. Fayrer observes, no doubt be large, but the saving of human life thereby effected would be great.

OUR BOOK SHELF

Forstzoologie. Von Dr. Bernard Altum. I. Saügethiere. (Berlin: Springer, 1872. London: Williams and Norgate.)

Academy of Forestry at Neustadt-Eberswald, gives us, in

DR. BERNARD ALTUM, Professor of Zoology in the Royal

Sce page 31 of Dr. Fayrer's work.

the present volume, the first of a series of essays which he proposes to write for the instruction of his pupils and others in "Forest-zoology," i.e., in Zoology with especial reference to the wants of those who are engaged in the care and preservation of forests. The present volume is devoted to the class of Mammals; a second will relate to the Birds; and a third to the Insects; these being the three principal divisions of the animal kingdom with which "foresters" are mostly brought into contact. Zoology in the abstract, or "scientific zoology," Dr. Altum observes, is the foundation upon which all knowledge of the various applications of zoology must be based. Dr. Altum therefore adopts a strictly scientific arrangement for his work, commencing with a definition of the class of Mammals, and taking the various groups of this class in systematic order. The work being intended for those whose labours are to be in the forests of Central Europe, only European species are included. But the Quadrumana, Prosimia, and other orders restricted to foreign countries, are introduced in their proper places, and some general information concerning them, together with a short account of their leading divisions, is given. Special attention is paid to those species of Mammals which the forester is most likely to be brought into contact with, such as the squirrels, field-mice, beaver, deer, and others; and full particulars are given of the modes in which forest trees are injured or attacked by them.

Dr. Altum's volume, thus composed, seems to be in every way well adapted for the purpose for which it is intended. Dr. Altum is fortunate in having, in Blasius' well-known work on European Mammals, an excellent guide to the scientific history of other animals, which he wisely follows. An English writer on the same subject would not be so well off, for the only modern work on British Mammals is now long ago out of print, and there seems to be no prospect of a second edition of it being published. In this, as in nearly every other branch of science, we have constantly to go to Germany for assist

ance.

LETTERS TO THE EDITOR

[The Editor does not hold himself responsible for opinions expressed by his correspondents. No notice is taken of anonymous communications.]

The Meteorology of the Future

I CANNOT quite agree with Mr. Lockyer that the most important question in meteorology is the discovery of a cycle. Were it even so well proved, it would still be but an empirical law. In my opinion the chief desideratum of the science is a dynamical theory of barometric waves; and the data for this are to be found not merely in records of barometric fluctuations in one place, nor by comparing the records in several places at or near the sea level, but by comparing the records at places separated by the greatest possible vertical distance, though horizontally near each other. Such records do not yet exist, and they can be had only at specially chosen stations; the summit and the base of Teneriffe, for instance, or of Etna. The latter would probably be the best, as it is in the variables. It is not at all certain that the fluctuations of the barometer at the summit and at the base of a high mountain would be nearly alike. It is stated by Kaenitz that while the barometer in the hottest part of the day falls at the sea level, it rises at a height of a few thousand feet. The reason why it rises at the higher station is that the entire column of air is lifted up by the expansion due to heat, and thus a larger proportion of the column comes to be above the station. This cause does not act at the sea-level, and the barometer there falls in consequence of the outflow of air from the top of the column. It is much to be desired that the attention of scientific men and scientific committees should be directed to this subject, as without such sets of comparative observations we shall never have all the data for a complete theory of barometric waves.

Old Forge, Dunmurry

JOSEPH JOHN MURPHY

Popular Science in 1872

SCIENTIFIC information in a popular form is one of the demands of the age, and we find it supplied even in publications by no means exclusively devoted to Science. It would be a great loss, however, to the professed students of science, if they should remain unacquainted with the following remarkable contribu tions to our knowledge of electricity, merely because they occur in the December number of Belgravia, in an article entitled "Is Electricity Life?"

"The ocean, for instance, is compounded of water and salt; one is an electric, the other not. The friction of these causes the phosphorescent appearance so often observed at sea.

"That all created living bodies are electric there can be no question; and as little that some persons, animals, and plants, are more electric than others. Two forms of the latter are familiar. Few schoolboys are guiltless of experiments on poor puss, from whose much-enduring back electric sparks may be drawn, especially in dry frosty weather; and most young ladies have admired the elegant sensitive plant, whose leaves seem to move and feel,

"and with quick horror fly the neighbouring hand,"

that draws from it the electricity which it contains more than supply of electric force renders them once more turgid. other plants; and its leaves at once fall flaccidly, until a new

But bodies have not only electricity within them, but an electric atmosphere, of the form of the body which it surrounds, and which is attracted by it. Without this we could not shake hands with a friend, or kiss a lip, without the danger of the excess of electricity flying off and destroying us, or the he or she that we would greet or kiss. Perhaps it is the commingling of these electric atmospheres that makes kissing so nice.

"Two conditions of the human body are also illustrative of its varied electric action. A person who has the small-pox cannot be electrified, while sparks of electricity may be drawn from the body of a patient dying of cholera. In the first instance since it is impossible to electrify a body beyond a certain degree; it appears that the body is fully charged with its own electricity, in the latter there seems to be a tendency to part with the electric force which is essential to the support of life, and which may account for the distressing and rapid weakness of cholerapatients."

Upon the Direction in which the North Magnetic Pole has moved during the last two Centuries

IN an article upon Terrestrial Magnetism in the current number of the Edinburgh Review, referring to the fact that the compass-needle does not now in England point due north and south, and that it changes its position slightly from year to year, but that from our present ignorance of the source and laws of this change we cannot say that it will hereafter be as much in one direction as it has been in another, the writer remarks (p. 424): "Still the strictly progressive character of this change compels us to regard it as the expression of some determinate cause or causes. The question then arises, Where are these to be found? Now, from whatever point on the earth's surface we contemplate the phenomenon, we find ourselves in the presence of two distinct magnetic systems. This was first clearly recognised by Halley as a necessary conse quence of even the scanty information at his command, and the accumulated observations of two hundred years have corroborated in a very remarkable manner the conclusions at which he arrived -that of these two systems one was fixed and the other in motion."

It is a matter of some interest to ascertain in what directions the system in motion has gone in the interval mentioned. Sir Edward Sabine gives us some information on this point. In his paper upon Terrestrial Magnetism, in "Johnston's Physical Atlas," p. 72, he says: "The change of longitude of the stronger pole, since Halley placed it on or about the middle of California, appears to have been small; but, on the other hand, the weaker pole, which is now found in Siberia, was placed by Halley near the meridian of the British Islands, and, adopting Halley's mode of reasoning, the present disposition of the lines of declination corresponds to this change.'

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Of the northern poles of the two magnetic systems in Halley's time, one appears to have been in the longitude of California, the

other in that of the British Islands, the former being stationary, the latter in motion; and as it is said now to be Siberia, its motion must have been from west to east. On the other hand, we find this motion described as being in the opposite direction, viz., from east to west. Sir George Airy, in his treatise on Magnetism, p. 93, remarks "that at Greenwich the dip and total force are diminishing. Interpreting these by the remarks, it would seem that the magnetic equator is approaching above Greenwich, or the north magnetic pole is receding from Greenwich; and remarking also the westerly change in direction of north magnetic meridian, from the sixteenth century to the year 1824, and its subsequent easterly motion, it would seem that the north magnetic pole has rotated round the terrestrial pole in a small circle from east to west, and, having passed the point where its westerly azimuth, as viewed from Greenwich, is maximum, is still continuing its course in that circle. It seems probable that in the fifteenth or sixteenth century it was situated between North Cape and Spitzbergen. It is now north-west of Hudson's Bay."

The north magnetic pole, which Sir E. Sabine supposes to have been in Halley's time in the meridian of the British Islands, would appear to be the same which Sir G. Airy says was probably in the 13th and 16th century in a meridian between North Cape and Spitzbergen; yet the pole referred to is in one case said to be now in Siberia; while in the other it is said to be to the north-west of Hudson's Bay; but it cannot at the same time have gone to the eastward and also to the westward.

In the two accounts there is a discrepancy, but perhaps this is apparent only, and some of your readers may be able to show how the accounts can be reconciled. X

Height of Thunderclouds

A FEW days ago I had an opportunity of estimating the height of a bank of thunderclouds, an account of which may interest the readers of NATURE.

I was camped at Gurpur, a place some eight miles from and within sight of the sea, with an elevation of about 480 feet. The evening was fine, and the horizon to westward remarkably free from haze, so much so that when the sun dipped it was still too bright for the naked eye to bear. Some fifteen or eighteen miles to eastward a heavy thunderstorm was raging, and the Western Ghats were shrouded by immense masses of cumulus, which, piled up to an enormous height, and rosy with the beams of the setting sun, formed quite a study for an artist.

Having been in the jungles for three or four weeks, I noted, in order to get correct time, the moment the sun disappeared beneath the horizon. This was, by my watch, six minutes past six o'clock. A few minutes subsequently I noticed the earthshadow creeping up the clouds to eastwards, its edge being singu larly well-defined by the contrast of the cold grey beneath and the warm colouring above. Struck by the slow progress of the shadow, I timed it, and found that at seventeen minutes past six the last tinge of pink faded from the highest point of the cumulus, and at nineteen and a quarter minutes the cirrhi floating above the storm lost their hue, thus giving eleven minutes for the former and thirteen and a quarter for the latter. These times reduced and corrected for latitude (130° N.), give the respective approximate heights of the clouds as 14,075 and 25,590 feet, or, adding height of observer, about 2'75 and 4'93 miles.

To be on the safe side, but 10' of arc have been allowed for the eastward position of the clouds. The nature of the observations of course renders correction for refraction unnecessary, so that the above figures are well within the mark.

I believe that in the tropics cumuli attain a considerably In 1864 I was on greater elevation than is generally believed. board a vessel in lat. 2° 53' N., long. 10° 47′ W., when there were constant flashes of forked lightning visible among detached clouds directly overhead, yet not the faintest growl of thunder was heard by anyone on board, although a dead calm prevailed at the time. This fact I can only attribute to the combined effect of the immense altitude of the clouds and the consequent rarity of the air. E. H. PRINGLE

Mangalore, South Canara, Nov. 2

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plement to the important article by Mr. Lockyer in NATURE for Dec. 12.

Meteorologists have been hunting for a Saros throughout the present century. Among them, perhaps, the most devoted to the subject were Lieut. George Mackenzie, author of "The System of the Weather," and Luke Howard, whose "Cycle of Eighteen Years in the Seasons of Britain" is a well-known work.

What little I have done in the subject is briefly told. Almost immediately after commencing the collection of British rainfall statistics, which has now reached a completeness excelling that of any other country, my attention was naturally drawn to the question of periodicity. Knowing, however, something of the care requisite to obtain long series of observations strictly comparable, I waited five years before printing anything bearing upon it; in 1865, however, I prepared and published the following table for fifty years, based upon the mean of continuous records in different parts of Great Britain :TABLE I-MEAN DEPTH OF RAIN AT TEN STATIONS, 1815-1864

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I also called attention to two features in this table, which strongly tend towards the confirmation of Mr. Meldrum's views, viz. :-(1) that the wettest years are 1836, 1841, 1848, 1852, and 1860; (2) that of these, all but two form a 12-year period, viz., 1836, 1848, 1860, to which we may now add 1872†; (3) that the dry years were 1826, 1834, 1844, 1854, 1855, 1858, and 1864; (4) that of these, all but three form a 10-year period, viz., 1834, 1844, 1854, and 1864.

All this looked very satisfactory; but, to make assurance doubly sure, I determined to make up a longer period. This I accordingly did; and the approximate fluctuation of annual rainfall during one hundred and forty years, viz., 1726 to 1865, will be found in the British Association Report for 1866, page 286, et seq. These values were converted into ratios, and, subsequently, those for the years 1866 to 1869 were added, and the table was given in the following condensed form in an article on the "Secular Variation of Rainfall in England since 1725,"

TABLE II.-RATIO OF THE FALL OF RAIN IN EACH YEAR SINCE 1725 TO THE MEAN FALL OF SIXTY YEARS, ENDING WITH 1869

88165 71 58

75

131 117 91 93

Year. 1720 1730 1740 1750 1760 1770 1780 1790 1800 1810 1820 1830 1840 1850 1860 61 70 108 86 90 100 92 III 89 QI 122 108 87 70 79 105 96 98 109 108 128 88 92 82 71 III 97 100 98 138 107 91 87 118 113 86 77 92 117 106 110 ΙΟΙ .89 76, 101 129 96 104 85 92 117 90 85 74 73 83' 82 123 77 84 75 99 96 99 97 88 108 I-7 77 107 107 83 96 77 118 108 93 115 110 95 1 93 91 8) 96 106 94 | 100 102 87 90 109 70 65 84 123 102 65 88 90 102 120 90 130 80 59 81 85 83 116 106 88 99 102 107 98

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8365 71 60 114 89 102 80

100 101 70

102

9

97

Mean

100

97 103

80 102

102 104

89'9 706 855 91'1 103'5 935 96'5 88'2 98'6 103'2 101'4 102'6 95'2 101'5

in "British Rainfall, 1870." I was so disappointed at the total disappearance of both the ten- and twelve-year periods, that I cannot say that I have closely scrutinised * Brit. Assoc. Report, 1865, p. 202. + See Times, Nov. 12 and Dec. 3, 1872.

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