ON the morning of August 17, about 3 a.m., a remarkable phenomenon attracted attention at the Island of Rügen, in the Baltic. A deep rumbling out at sea was heard, and soon afterwards two enormous waves approached from the northwest, breaking over the shore and doing considerable damage to small craft. At the time the sea was calm, and there was no wind.

ON the night of July 31 a brilliant meteor was seen at Linköping, in Sweden, going in a north-westerly direction. It finally burst, the fragments appearing to fall near the railway park.

Symons's Monthly Meteorological Magazine for August contains an interesting summary of the climate of the British Empire during 1887. Comparing with the summary for 1886, Stanley, Falkland Isles, takes the place of London, as the dampest station. Adelaide has the highest shade temperature, 111°2; the highest temperature in the sun, 164; and is the driest station. Winnipeg has the lowest shade temperature, - 42° 7, and the grea est yearly range, 135° 9. Bombay has the greatest rainfall, and Malta the least, and also the least cloud. Although the maximum shade temperatures in Australia exceed those in India, the average maxima of the latter far exceed those of Australia.

THE Pilot Chart of the North Atlantic Ocean for August shows that although the weather over that ocean was generally fine and very mild during July, a number of depressions were generated, and produced gales over the trans-Atlantic routes. The most violent was one which developed on June 27, in about latitu le 42 and longitude 52`, teaching our coa ts on July 4. A wind force as high as 11 of the Beaufort scale was recorded during its course. Dense continuous fog was encountered over and to the westward of the Grand Banks. Large quantities of ice have been reported as far west as the 60th meridian. The tracks of all the most notable August hurricanes on record are plotted on the chart, and show where these dangerous cyclones are likely to be encountered. A supplementary chart showing the derelicts in the North Atlantic, gives also the complete history up to date of the great log raft which was abandoned last December. This most dangerous obstruction to navigation consisted of about 27,000 trunks of trees bound together, and measured 560 feet long. Thousands of the great logs of which it was composed are still drifting over the commercial routes.

IN the American Meteorological Journal for July, Lieut. Glassford describes a new wind vane in use at the California State University. The design is said to possess novel advantages, such as supporting all the weight upon a point, like a compass-card, an oil vessel into which paddles dip to lessen the suddenness of vibration, &c. It may here be mentioned that anemometers with liquid brakes have also been made in this country. Mr. Rotch contributes an article on the Observatory on the Säntis, in Switzerland. The observations of this mountain station are regularly published in the Annalen of the Swiss Central Meteorological Office. Mr. F. Waldo gives an abstract of the results of comparisons of several of the combined cisternsyphon barometers, known as the Wild Fuess check barometers. These portable instruments have been for some time in use in Russia, and some of them are now introduced into the United States Signal Service. The full account of the comparisons was prepared for the Chief Signal Officer's Report, but is not yet printed.

DR. G. N. STEWART, Owens College, sent recently to the Royal Society of Edinburgh a preliminary communication on the electrolytic decomposition of proteids. He pointed out that it is an important question whether the conduction of electricity by animal tissues is mainly or entirely electrolytic. If it is mainly electrolytic, the further question becomes interesting,

What are the electrolytes? The inquiry is thus brought int relation with the whole of electro-physiology on the one hand, and the whole of electro-therapeutics on the other, and, at the present moment, it gains special interest from the practical point of view, in connection with the recent introduction of strong currents into gynecological treatment. The investigation is as yet far from being complete, and Dr. Stewart is at prese it carrying on the experiments. In the case of egg-albumen it has been found that the resistance at any given temperature is no dialysis. The conclusion is that it is, mainly at any rate, by the changed by coagulation, but that it is enormously increased by electrolysis of the simple inorganic constituents that the curren: passes.

A THIRD edition of Prof. Silvanus P. Thompson's "DynamoElectric Machinery" (E. and F. N. Spon) has just been issued Most of the treatise has been rewritten for this edition, and much new matter has been added.

THE University College of North Wales has issued its Calendar for the year 1888-89.

IN the Annual Report, for the year 1887, of the Trustees cf the American Museum of Natural History, Central Park, New York City, it is stated that the collections of this Museum are now valued at the sum of about 600,000 dollars. "It is fut

right to say," add the Trustees, "that of this large amount your Trustees have been the main contributors. The necessity of adding to these collections increases as time goes on, and it is hoped that more of our citizens will take an earnest and increased interest in our Museum, and so aid the Trustees in making this institution what it should be and what our city has a right to expect the great museum of the country."

IN a letter written on board the seal-ship Jason in the Denmark Sound, Dr. Nansen draws attention to the scarcity of seals on the coast of Greenland in recent years. Only ten years ago the animals were so plentiful and tame that thousands could be

clubbed" with the greatest case, whereas now they have become scarce and shy. Dr. Nansen is of opinion that the ruthless persecution of these animals since 1876, when the first sealer appeared in the Denmark Sound, has caused them to alter their habits. Formerly they were found on the edge of the driftice, where they were safe from their only enemy, the Polar bear, though falling an easy prey to the sealer. Now they gather on the ice close to the shore, whither vessels cannot penetrate, and where they are, at all events, safe from one enemy. This, says Dr. Nansen, was fully demonstrated on several occasions, particularly on July 2, when seals were seen lying in thousands close under the shore to the north and northeast as far as the eye could reach from the mast head. To the north especially the ice was for miles one mass of dark animals. | Dr. Nansen advocates a closer preservation of the seal. The seal fishery was a failure this year, and sealers report that the ice-masses were enormous.

THE additions to the Zoological Society's Gardens during the past week include three Black-headed Lemurs (Lemur brunneus » from Madagascar, presented by Captain J. Bonneville; a Ringtailed Coati (Nasua rufa) from South America, presented by Captain James Smith; a Razorbill (Alca terda), British, presented by Mr. T. H. Nelson; a Nightingale Daulias luscinia), British, presented by Mr. J. Young; an American Wild Turkey (Meleagris gallo pavo 8 ) from North America, presented by Mr. F. J. Coleridge Boles; a Raven Corvus corax), British, presented by Mr. F. Steinhoff; two Pallas's Sand Grouse (Syrrhaftes paradoxus', bred in Fifeshire, N.B., presented by Mr. Alexander Speedie; a Macaque Monkey (Macacus cynomolgus 8) from India, a Lesser White-nosed Monkey (Cercopithecus petaurista from West Africa, a Vulpine Squirrel (Sciuru.

At Greenwich on September 2

Sun rises, 5h. 17m. ; souths, 11h. 59m. 216s. ; sets, 18h. 42m. : right asc. on meridian, 10h. 476m.; decl. 7° 40′ N. Sidereal Time at Sunset. 17h. 31m.

Moon (New on September 6, 5h.) rises, oh. 39m. : souths, 8h. 49 n.; sets, 16h. 55m. : right asc. on meridian, 7h. 37°2m.; decl. 20° 54' N.

OUR ASTRONOMICAL COLUMN.

THE SPECTRUM OF R CYGNI.-The Rev. T. E. Espin, in Circular No. 21 of the Wolsingham Observatory, reports that he observed a remarkably bright line (apparently F) in the spectrum of this star on August 13. The observation was confirmed on August 22, on which night Dr. Copeland also observed the bright line and determined its position. Dunér's observations of this star in 1879, 1880, and 1882 showed it as possessing a feebly-marked spectrum of the third (Secchi's) type. A change would therefore seem to have taken place in this star. Place for 18870, R. A. 19h. 33m. 49s., Decl. 49° 57' o N.

MILAN DOUBLE-STAR OBSERVATIONS.-Prof. Schiaparelli has recently published, in No. xxxiii. of the Publications of the Royal Observatory of Brera, the results of his measures of 465 systems of double stars made with the fine 8-inch Merz refractor of that Observatory in the eleven years 1875-85. The observations are nearly 4000 in number, and are for the most part of stars of small distances, i.e. less than 5", apart, the binaries in rapid motion receiving especial attention. The measures are grouped together into four parts, the stars of the Dorpat and P'ulkowa catalogues forming the first two, then follow stars discovered by Burnham, and those of other discoverers are grouped together in the last. Besides these detailed results of the measures made with the old 8-inch, with which Prof. Schiaparelli has done so much excellent work in the past, there are given in an appendix mean results for a number of the closest pairs as measured with the new 18-inch refractor. Prof. Schiaparelli seems well satisfied with the performance of this new instrument, and records the discovery that the principal star of Σ 1273, € Hydræ, is itself a very close double, a fact that had hitherto escaped notice, notwithstanding the number of observations which have been made with various telescopes upon the star. The magnitudes of the two components of the new double are 4 and 5'5, and the distance is o" 2 or o" 25. The earlier part of the volume contains a detailed description of the optical performance of the 8-inch refractor, a discussion of the errors of the micrometer and of the accidental errors of observation, a determination of the systematic errors of observation, and a very full comparison with Dembowski's measures. The differences in the determination of position-angle due to the varying inclination of the lire joining the two stars to the line of the observer's eyes are also investigated, but the reversion prism was not used. Prof. Schiaparelli finds that on the whole his measures of distance are free from systematic errors due to personality, but his position-angles have a tendency to be small as compared with those of other observers.

Amongst the notes to some of the more interesting stars is one on O 285 in which a correction of 180° is suggested to the angles of Englemann and Perrotin in 1883 and 1885, the star being supposed to have passed rapidly through periastron in the long period from 1865 to 1883, in which it was unobserved. All the observations would then be satisfied by an ellipse of 100 years of revolution. 2367 and 2525 are noted as appearing

as single stars with the 18-inch refractor in 1887.

ENCKE'S COMET.-Mr. John Tebbutt, Windsor, New South Wales, informs us that he picked up this object on the evening of July 8. Its place as observed closely accorded with that given in Dr. Backlund's ephemeris.

ASTRONOMICAL PHENOMENA FOR THE WEEK 1888 SEPTEMBER 2-8.

(FOR the reckoning of time the civil day, commencing at Greenwich mean midnight, counting the hours on to 24, is here employed.)

Planet. Rises. h. m.

Venus.....

Mars

2 ...

635

12 26

Jupiter.. 12 38 Saturn.... 2 43

Right asc. and declination

on meridian.

m.

...

16.58

Uranus... 8 33 14 9

...

...

* Indicates that the rising is that of the preceding evening. Occultations of Stars by the Moon (visible at Greenwich).

2 ...

Reap.

h. m.

Star.

Mag.

Disap.

0 50

3 Sept.

7

Corresponding angles from vertex to right for inverted image.

84 216

4 54 near approach 135

Saturn in conjunction with and o° 34' south

M signifies maximum; m minimum; m, secondary minimum.

O M O m

THE current number of the Proceedings of the Royal Geographical Society contains the report of his first year's work by Mr. Mackinder, the Reader in Geography to the University of Oxford, whose appointment is due to the Society. He describes the year as one of reconnoitre and preparation; nevertheles he delivered forty-two ordinary lectures in the University, and one public lecture; in each of the three terms he lectured for seven weeks twice a week, having two courses going on side by side on different days, to one of which he imparted a scientific, to the other an historical bias. The notices were, by permission of the Board of Faculties, published in the lists of two separate Faculties-Natural Science and Modern History. On the scientific side the lectures have been on the principles of geography-“a review of the subject not merely physical, yet taking the feature, and not the region, as the basis of classification. This course has not been so well attended as the other, but Mr. Mackinder congratulates himself that he has never been wholly without an audience, "a fate not altogether unknown just now to Oxford Professors and Readers." On the historical side the lectures were on the geography of Central Europe, and the influence of physical features on man's movements and settlements. "My aim is

to furnish general instruction to as large a number as will favour me with their attention; and also to have always round me two or three whom we may style specialists. I can only say that I now see a very fair prospect of obtaining the latter. It may be well to place on record my humble opinion, that the best preliminary training for a geographical specialist is sound grounding in general science, and superadded to this an elementary knowledge of history. I have found by experience that it is exceedingly hard to give the necessary scientific knowledge to an historian"-a somewhat hard saying for the historians. In the coming academical year the lectures will be on the physical geography of continents, the geography of the British Isles, and the historical geography of North America. As Extension Lecturer, Mr. Mackinder has delivered 102 lectures on geography and physiography at various towns throughout the country.

IN the August number of the Scottish Geographical Magazine, Mr. Forbes reports on his attempts to reach the Owen Stanley Peak, and incidentally describes the moving adventures by flood and field of his last expedition. Although not successful, owing to more than one unexpected mishap, in reaching his goal, he claims that the results accomplished so far have not been few or inconsiderable. Large additions have been made to botanical and some to zoological science; an extensive series of meteorological observations has been tabulated, and a tract of country has been mapped for the first time. Mr. Ravenstein briefly describes the recent explorations in the territories of the African Lakes Company between Nyassa and Tanganyika. Both these papers are accompanied by excellent maps. Archdeacon Maples, of the Universities Mission to Central Africa, gives a detailed account of Lukoma, the principal island in Lake Nyassa, which, although only 4 miles long by 24 broad, has a population of 2500, or about 220 to the square mile, in consequence of its comparative freedom from war. "Ula," or witchcraft, of the kini described by Mr. Rider Haggard with such graphic force in one of his earlier works, prevails, and is a curse to the island. Herr Metzger contributes a most interesting paper on the scientific work lately done in the Dutch East Indies, based mainly on recent Government publications and those of various learned Societies in Holland and Java.

THE current number of the Deutsche Geographische Blätter contains two papers of considerable geographical and ethnological interest. The first, by Herr August Fitzau, is devoted to the little-known region of the north-west African seaboard between Morocco and the Senegal River. After an historical survey of the various attempts made to found European settlements in this region, the writer describes in detail the sections of the coast between Agadir and Cape Juby, and thence to Saint Louis. He then deals with the Western Sahara in general, and especially with the ethnological relations of the regions south of the Atlas and north of the Senegal River, arriving at the general conclusion that, although Arabic has become the dominant language, the old Berber or Hamitic is still the prevailing ethnical element, variously modified by Semitic and Negro influences. In the second paper the distinguished traveller and ethnologist, Dr. O. Finsch, gives a sympathetic and permanently valuable account of the life and work of the late MikluhoMaclay, to whom anthropological science is so much indebted for his profound studies of the Malayan, Papuan, Negrito, Melanesian, and Australian races. The memoir is very complete, including a detailed account of the naturalist's travels with their scientific results, his vast ethnological collections and the zoological stations founded by him, and concluding with a full descriptive catalogue of his numerous geographical, anthropological, and zoological writings.

THE July number of the Bollettino of the Italian Geographical Society is mainly occupied with Leonardo Fea's recent explorations in Tenasserim. The chief points visited were the curious "Farm Caves in the Moulmein district, and Mount Mulai (Moolaee) in the Dona Range. This peak, culminating point of Tenasserim (6300 feet), was reached and ascended to its summit after a journey full of difficulties and hardships, which followed the course of the Jeeayng-Myit and its great southern tributary, the Undurò, as far as Meetan in 46° N., 98° 30′ E. Meetan the route struck north to Tagata and Mulai through the hilly territory of the little-known Ayaeen Karens. Of this tribe Signor Fea gives an interesting account, and he was also successful in securing a large zoological collection, including 450 skins of birds, over 400 mammals, many hundred reptiles, batrachians, and fishes, besides numerous insects, spiders,

From

mollusks, and other small animals. These treasures go to em the valuable zoological materials already brought together ne Natural History Museum founded at Genoa by the Ma Giacomo Doria. The paper is accompanied by a map of the region explored, as well as by several original sketches by the naturalist himself. The Marquis Doria has added a useful lir of the various memoirs that have appeared in connection: Signor Fea's geographical and biological researchies in Burh during the last four years.

THE most important amongst recent explorations in Ind China are those undertaken by the Vice-Consul for France Luang Prabang, the capital of an outlying region of Siam of the same name, and itself situated on the Mekong. M. Pavie, the official in question, has since succeeded in reaching Tonquin from this place by two different routes, the most practicable apparently being that to the north-east along the valley of the Namseng a tributary of the Mekong, and then across the mountains forming the watershed of the Mekong and Songkoi, or Red River of Tonquin, to the valley of Nam Tay or Black River, down which M. Pavie proceeded to Sontay and Hanoi.

He ha

AT a recent meeting of the Swedish Geographical and Anthropological Society, Baron H. von Schwerin gave account of his late expedition to the Congo and West Africa. extending over a period of nearly two years, and undertaken at the instance of the Swedish Government. proceeded in a steamer as far up the Congo as Stanley Falls, and then up the Kassai, the principal tributary of the former. Next he had, in the company of bis countryman, Lieut. C. Håkansson, explored the basin of the Inkissi, another tributary of the Congo, and from Banana made an excursion into the land of the Mushirongi, south of the mouth of the river, a country never hitherto visited by any European. After a journey to Angola and Mossamedes, on the west coast, a journey performed in a sailing-vessel, and extending as far north as Cape Negro, he made an excursion into the lands of Kakongo and Kabinda, situated to the north of the mouth of the Congo, which had also hitherto been considered closed to Europeans. The heat on the Congo was not so excessive as was generally imagined. A temperature above 35° C. was rare, but what were particularly enervating and exhausting were the steadiness of the high temperature and the total absence of cooling breezes, whether in the shade or at night, and, more than either, the exce sive humidity of the air. He considered the climate of the Congo one of the healthiest in Africa. Finally, Dr. Schwerin gave an account of his discovery on the promontory south of the Congo River of the remains of the marble pillar raised there in 1484 by Diego Cam in commemoration of the discovery of this mighty river, and destroyed by the Dutch in the sixteenth century. The speaker also exhibited a large and valuable collection of scientific objects gathered in Africa.

A

NOTES ON METEORITES.

I.

THEIR FALL AND PHYSICAL CHARACTERISTICS. PERUSAL of the Chinese annals-which reach back to the year 644 before our era, and are still models of patient record-or of the muca more irregular and less complete ones of the Western world, shows in the most definite manner that since the very commencement of human history, from time to time falls of bodies on to the earth from external space have been noticed. Biot has traced in Ma-tuan-lin the record of sixteen falls from the date before mentioned to A. D. 333.

The earliest fall recorded in Europe, however, transcends in antiquity anything the Chinese can claim, dating as it does from 1478 B.C. It happened in Crete, but the record is much more doubtful than that of the falls in 705 and 654 B.C., noted, the first by Plutarch, and the second by Livy.

But in 466 B.C. occurred a fall at Aegos Potamos, in Thrace, concerning which the Chronicles of the Parian marbles, Plutarch, and Pliny all give us information. It was of the size of two mill-stones, and equal in weight to a full waggon-load.1 Later, there fell in Phrygia, in about the year 2 4 B. C., a stone famous through long ages, which was preserved there for many genera tions. It was described as "a black stone, in the figure of a cone, circular below and ending in an apex above." It was worshipped by the ancients as Cybele, the mother of the gods, Humboldt, "Cosmos," Otte's translation, vol. i. p. 103.

and was transferred to Rome, as an oracle had announced that the possession of it would secure continual prosperity to the State.1

In more modern times we have records of various falls of these bodies. The following-a few out of a very great number-either possess a national interest or are the statements of eye-witnesses.

In England there fell a stone in the afternoon of December 13, 1795. A labourer happened to be working near Wold Cottage, Thwing, Yorkshire, when this stone fell within a few yards of him. On digging the stone out of the ground it was found to have penetrated a foot of soil and half a foot of chalk rock, and to weigh 56 pounds. The inhabitants of the neighbouring villages likened the explosion to the firing of guns at sea, while in two of them the sounds were so distinct of something rushing through the air towards Wold Cottage that some of the people went to see if anything extraordinary had happened.

The next account is from Ireland. It is the narrative of an eye-witness of a fall of meteorites in the county of Limerick.

"Friday morning, the 10th of September, 1813, being very calm and serene, and the sky clear, about 9 o'clock, a cloud appeared in the east, and very soon after I heard eleven distinct reports appearing to proceed thence, somewhat resembling the discharge of heavy artillery. Immediately after this followed a considerable noise not unlike the beating of a large drum, which was succeeded by an uproar resembling the continued discharge of musketry in line. The sky above the place whence this noise appeared to issue became darkened and very much disturbed, making a hissing noise, and from thence appeared to issue with great violence different masses of matter, which directed their course with great velocity in a horizontal direction towards the west. One of these was observed to descend; it fell to the earth, and sank into it more than a foot and a half, on the lands of Scagh, in the neighbourhood of Patrick's Well, in the county of Limerick. It was immediately dug up, and I have been informed by those that were present, and on whom I could rely, that it was then warm and had a sulphurous smell. It weighed about 17 pounds, and had no appearance of having been fractured in any part, for the whole of its surface was uniformly smooth and black, as if affected by sulphur or gunpowder. Six or seven more of the same kind of masses, but smaller, and fractured, as if shattered from each other or from larger ones, descended at the same time with great velocity in different places between the lands of Scagh and the village of Adare. One more very large mass passed with great rapidity and considerable noise at a small distance from me; it came to the ground on the lands of Brasky, and penetrated a very hard and dry earth about 2 feet.

This

was not taken up for two days; it appeared to be fractured in many places, and weighed about 65 pounds! Its shape was rather round, but irregular. It cannot be ascertained whether the small fragments which came down at the same time corresponded with the fractures of this large stone in shape or number, but the unfractured part of the surface has the same appearance as the one first mentioned. There fell also at the same time, or the lands of Faha, another stone, which does not appear to have been part of or separated from any other mass; its skin is smooth and blackish, of the same appearance with the first-mentioned; it weighed about 74 pounds; its shape was very irregular, for its volume was very heavy. It was about three miles in a direct line from the lands of Brasky, where the very large stone descended, to the place where the small ones fell in Adare, and all the others fell intermediately; but they appeared to descend horizontally, and as if discharged from a bomb and scattered in the air." 2

The fall of the meteorite of 1885, near Mazapil, in Mexico, was thus described by an eye-witness vouched for by Prof. Bonilla :- 3

"It was about nine in the evening when I went to the corral to feed certain horses, when suddenly I heard a loud hissing noise, exactly as though something red hot was being plunged into cold water, and almost instantly there followed a somewhat loud thud. At once the corral was covered with a phosphorescent light and suspended in the air were small luminous sparks as though from a rocket. I had not recovered from my surprise when I saw this luminous air disappear, and there remained on the ground only such a light as is made when a match is rubbed. A number of people from the neighbouring houses

came running toward me, and they assisted me to quiet the horses, which had become very much excited. We all asked each other what could be the matter, and we were afraid to walk in the corral for fear of getting burned. When, in a few moments, we had recovered from our surprise, we saw the phosphorescent light disappear, little by little, and when we had brought lights to look for the cause, we found a hole in the ground and in it a ball of fire. We retired to a distance, fearing it would explode and harm us. Looking up to the sky we saw from time to time exhalations or stars,' which soon went out, but without noise. We returned after a little, and found in the hole a hot stone, which we could barely handle, which on the next day we saw looked like a piece of iron; all night it rained stars, but we saw none fall to the ground, as they seemed to be extinguished while still very high up."

The next record of the phenomena attending a fall in the United States (though the observer quoted did not actually see the fall) is taken from a lecture by Prof. Newton :— 2

"The observers,' he says, 'who stood near to the line of the meteor's flight, were quite overcome with fear, as it seemed to come down upon them with a rapid increase of size and brilliancy, many of them wishing for a place of safety, but not having the time to seek one. In this fright the animals took a part, horses shying, rearing, and plunging to get away, and dogs retreating and barking with signs of fear. The meteor gave out several marked flashes in its course, one more noticeable than the rest.

Thin clouds of smoke and vapour followed in the track of the meteor. . . . From one and a half to two minutes after the dazzling, terrifying, and swiftly moving mass of light had extinguished itself in five sharp flashes, five quickly recurring reports were heard. The volume of sound was so great that the reverberations seemed to shake the earth to its foundations; buildings quaked and rattled, and the furniture that they contained jarred about as if shaken by an earthquake; in fact, many believed that an earthquake was in progress. Quickly succeeding, and blended with the explosions, came hollow bellowings and rattling sounds, mingled with clang, and clash, and roar, that rolled away southward, as if a tornado of fearful power was retreating upon the meteor's path.'

"About 800 pounds of stones, nearly 200 in number, have been picked up in a region seven miles by four, a little east of the end of the meteor's path, which without any doubt came from the meteor. Some were picked up on the surface of the frozen ground. One was found on the top of a snow-bank, and about 40 feet away were marks of a place where it had first struck the ground. Some were ploughed up in the spring. The two largest found, of 74 pounds and 48 pounds, fell by the roadside, and a lawsuit to settle whether they were the property of the finder as being wild game, or of the owner of the lands adjacent as being real estate, was decided in favour of the owner of the land."

In some cases of observed falls the rate of movement of the meteorite through the air has been determined, or concomitant circumstances have enabled it to be roughly estimated.

The velocities have been widely different. Before they are stated, s me terms of comparison may be given

The highest velocity of flight through the air has been that of the Stannern meteorites, 45 miles a second. The lower part of the flight of the Iowa meteorite was performed at 12 miles a second.

In only a few cases have the velocities been observed to be very great at the earth's surface, the retarding effect of the passage through the atmosphere being considerable. Some have buried themselves deeply in the ground, and one (New Concord) broke a railway-sleeper. Several meteorites have fallen so rapidly that the sound of the explosion followed them. generally the rate is so slow that they are not broken on striking 1 The meteor fell during a star-shower. NATURE, vol. xix. p. 315.

2

But

the surface, and some that fell at Hessle on ice only rebounded without cracking it.

These bodies, when they fall under such conditions that they can be picked up and examined, are called meteorites. The first thing that strikes one when looking for the first time at these meteorites, is that their general form has the character of being essentially fragmentary, indicating that what we see is the result of a fracture.

The next point observed is that there is a very great difference between the interior and exterior appearances of these bodies. That this is caused by the heat and friction to which the exterior surface is exposed is proved by what was noticed in the case of a meteorite that fell at Butsura in 1861. Fragments of this stone were picked up three or four miles apart, and, with the exception of one corner, the original meteorite has been built up again by piecing the fragments together. The faces fit perfectly. Important pieces of this meteorite are in the British Museum, and these are all coated with the cru t to which reference has been made. But, on the other hand, another of these fragments not coated fits another also not coated. Hence, to quote Prof. Maskelyne, "We can assert that this aerolite acquired, after coming into

our atmosphere, a scoriated and blackened surface or incrast tion. The first explosion drove the fragments first alluded asunder, and these became at once incrusted on their broker surfaces; but others which were separated afterwards, probe on the last of the three explosions, had not sufficient vei left [the heat being at the same time reduced] to cause ther incrustation in the same manner as was the case with th fragments previously severed."

The supposition is that the temperature is practically hi enough to melt the meteorite, and that its surface as w see it after it has fallen does not in all cases represent the surface exposed to the air during the whole of the fligh that it represents the last surface. The meteorite may h been twenty times bigger, but the rest may have been melted like tallow would be, so that finally there is very little visit effect towards the interior, as the melting is more rapid th the conduction. The thinness of the so called varnish, then. s caused by the air-molecules carrying away the results of for as fast as the heat penetrates towards the interior, so lea o ly, as a rule, a very thin film behind.

This crust is usually dull, but sometimes, as in the Stanrem meteorite, bright and shining, like a coating of black var

1

Sorby, cn examining with a microscope a thin section of a meteorite, cut perpendicular to the crust, found that it is a true black glass filled with small bubbles, and that the contrast between it and the main mass of the meteorite is as complete as possible, the junction between them being sharply defined, except when portions have been injected a short distance between the crystals. He writes: -- "We thus have a most complete proof of the conclusion that the black cru-t was due to the true igneous fusion of the surface under conditions which had little or no influence at a greater depth than 1/100 of an inch. In the case of meteorites of different chemical composition, the black crust has not retained a true glassy character, and is sometimes 1/50 of an inch in thickness, consisting of two very distinct layers, the internal showing particles of iron which have been neither melted nor oxidized, and the external showing that they have been oxidized an the oxide melted up with the surrounding stony matter. Taking everything into consideration, the microscopical structure of the crust agrees perfectly well with the explanation usually adopted, but rejected by some authors, that it was formed by the fusion of the external surface, and was due to the very I "On the Structure and Origin of Meteorites," NATURE, vol. xv. p. 495.

rapid heating which takes place when a body moving w planetary velocity rushes into the earth's atmosphere-a heati so rapid that the surface is melted before the heat has time penetrate beyond a very short distance into the interior the mass."

In some cases close under the crust is found a mixture of the minerals troilite, asmanite, and bronzite, of an unaltered lightbrown colour, although they turn deep black when raised to temperature slightly above that at which lead melts."

The crust or varnish of the meteorite in many cases contin numerous furrows and ridges, so that it is not equally th This effect is caused, as it is supposed, by its motion thro the air in a fixed position, the forward part of the meteorite. regard to its line of motion, being most liquefied, and the li flowing unequally towards the hinder part.

A very special study of the results of the passage through air is a desideratum. Thus, in the case of the Tennessee inc. which fell from a cloudless sky (and which therefore fell with low velocity?), the outer surface is elaborately reticulated, el