The survey starts from the extreme north, above Bering's Straits. It is curious, by the way, to see an American purist restoring the name of "Bering" to the Danish navigator's own spelling, and repudiating the Germanised form "Behring;" while, on the other hand, the Danes themselves are adopting this foreign form, and printing "Behr"Behrings-Straede in their maps. We first find classed as Esquimaux proper the wandering fishers who fringe the Arctic sea-coast down to Kotzebue Sound. The fullest information about this well-known race comes from the Greenland side, and Mr. Bancroft's account, taken from Western explorers, is scanty. He mentions, however, a crafty device used by them for killing the polar bear. The hunters bend pieces of stiff whalebone and freeze each into a ball of blubber; then they entice the bear to pursue them, dropping in his path the frozen balls, which he stops to swallow; when the blubber-balls thaw, the whalebones spring open, and put an end to the hapless beast. This trick was perhaps not known to the old Greenlanders. Passing farther south, we come to the Koniagas, a cluster of tribes ranging from Kotzebue Sound to the island of Kadiak. It is a somewhat interesting question, under what race these people are to be reckoned. Most ethnologists, includ ing Waitz, treat them simply as Esquimaux. Their languages, of which vocabularies are examined in Buschmann's great work on the North American languages, are distinctly Esquimaux dialects. This, indeed, is evident from their names of tribes, e.g., the Kwichpagmuts, "dwellers on the great river." The details of their civilisation, such as the use of labrets or lip-ornaments, their clothing, skin canoes, weapons, &c., have much correspondence with those of the Esquimaux. But, on the other hand, they are a taller people than the northern Esquimaux; and there is even a mention of a chief seven feet

high among them. Thus it is likely that they may be a cross between the Esquimaux and others. This is almost certainly the case with the next group of tribes, the inhabitants of the Aleutian Archipelago. It has been thought from the appearance of these Aleuts that they may be more or less of Asiatic origin, and they have a tradition that they came from Asia; while Buschmann (p. 702) shows that their language is a peculiar one, though containing a number of Esquimaux words. It thus seems not unlikely that ethnological materials may exist for working out the problem whether there has been any emigration of Asiatic tribes across Bering's Straits into America, as well as the insignificant Esquimaux migration into Asia.

Among the Thlinkits or Koloshes, in the district south of Mount St. Elias, a point deserving of notice is the fairness of the native complexion (p. 97), "as fair as many Europeans" (Langsdorff); "eran de color blanco y habia muchos con ojos azules " (Perez). Much the same is said of the Haidahs of Queen Charlotte's Island (p. 157), "fair in complexion, sometimes with ruddy cheeks (Hale), "their young women's skins are as clear and white as those of English women." From such accounts as these it appears that the North American

skin, deep yellow-brown or red-brown in most parts of the continent, lightens into remarkable fairness in this north-western district. But whether this is the result of natural change, or whether a fair race from the west has shared in the population, is quite unknown. Neither language nor custom has as yet thrown light on the complex ethnology of the west coast of North America.

Under the title of New Mexicans, Mr. Bancroft groups the tribes from California across to Texas. Mountain ranges, with desert plains between, furnish much of the geography of this wild land, where rove those fiercest of savage hordes, the Apaches and Comanches. In this region, under more favourable local conditions, are found also the Pueblo Indians of New Mexico and Arizona, who are semi-civilised town-people (Spanish pueblo town). The fortified houses of these people, which were first made known by the Spanish explorers of three centuries ago, are thus described (p. 534) :

:

"The towns of the Pueblos are essentially unique, and are the dominant features of these aboriginals. Some of them are planted in valleys, others on mesas (ie., plateaus); sometimes they are planted on elevations almost inaccessible, reached only by artificial grades, or by steps cut in the solid rock. . . . A Pueblo consists of one or more squares, each enclosed by three or four about 150 feet in width at the base, and from buildings of from 300 to 400 feet in length, and two to seven stories of from eight to nine feet each in height. . . . The stories are built in a series of gradations or retreating surfaces, decreasing in size as they rise, thus forming a succession of terraces. In front of the terraces is a parapet, which serves as a shelter for the inhabitants when

forced to defend themselves against an attack from wide, and extend round the three or four sides of the square, forming a wall for the occupants of the story resting upon it, and a roof for the story beneath; so with the stories above. As there is no inner communication with one another, the only means of mounting to them is by ladders, which stand at convenient distances along the several rows of terraces, and they may be drawn up sion. The outside walls of one or more of the at pleasure, thus cutting off all unwelcome intruof any kind, with the exception of, in some towns, lower stories are entirely solid, having no openings a few loopholes. The several stories of these huge structures are divided into multitudinous compartments of greater or lesser size, which are apportioned to the several families of the tribe.

the outside. These terraces are about six feet

are

flat, are formed of transverse beams which slope The roofs or ceilings, which are nearly slightly outward, the ends resting on the side walls; on these, to make the floor and terrace of the story above, is laid brushwood, then a layer of bark or thin slabs, and over all a thick covering of mud sufficient to render them watertight. The windows of the upper stories are made of flakes The rooms of selenite instead of glass. large, the substantial partitions are Houses are and neatly whitewashed. sist in building them; the men erect the wooden common property, and both men and women asframes, and the women make the mortar and build the walls. In place of lime for mortar, they mix ashes with earth and charcoal. They make adobes, or sun-dried bricks, by mixing ashes and earth with water, which is then moulded into large blocks and dried in the sun.

made of wood

Some of the

towns are built with stones laid in mud."

The Pueblo tribes who build these remarkable towns are, as may well be supposed, otherwise advanced in civilisation. The earliest European visitors describe them as

agriculturists, and their irrigation canals are made and kept in order by the community. They have what seems a native cleverness in such arts as weaving and wallpainting. Their organised system of town government existed in the time of Vazquez de Coronado (1540). It would, of course, be wrong to give these interesting people credit for the whole of their civilisation. Mr. Bancroft does not lay stress on the Spanish-Christian influence which was at one time strong among them, and though they have long since cast it off, to return in a measure to their old ways, yet it has left its effects. Thus, the famous name of Montezuma has been transplanted to become a legendary personage among them, and to be mixed up in their sun worship. They use the metate or mealing-stones, an instrument evidently imported from Mexico, and no doubt some Spaniard's hint led to their using selenite for window-panes. With all this, however, the native independent elements in Pueblo civilisation are well-marked, and we may, to a great extent, accept Mr. Bancroft's opinion that it was "a sponta neous awakening from the ruder phases of savagism" (p. 473), the Pueblos being "partially reclaimed Apaches or Comanches" (p. 476). From such an opinion, however, a practical inference must be drawn. If the same race who are in the desert the most irreclaimable of savages have become in the valleys a settled people half-way to civilisation, then it is scarcely open to doubt but that the "North American Indians" in general might, under favourable conditions and judicious treatment, have been absorbed into civilised life, instead of being "improved off the face of the earth."

EDWARD B. TYLOR.

CELSUS' ATTACK ON CHRISTIANITY.

Celsus' Wahres Wort, älteste Streitschrift antiker Weltanschauung gegen das Christenthum vom Jahr 178 n. Chr. Von Dr. Theodor Keim. (Zürich, 1873.)

ALTHOUGH this Essay has been published more than a year, it is not too late to recommend it very heartily to our readers, especially at a time when the history of the second century is so much discussed as it is at present. It belongs to a series of Dr. portance to the student of ecclesiastical Keim's writings which are of no little imhistory, though less known probably in this country than his recent work on the origin of Christianity. Many who regret most deeply the principles and conclusions of that laborious book will find much to sympathise with in these historical essays. In discussing, for instance, the date of the Epistle to Diognetus, he is a valuable ally against those who like Overbeck would assign it to the fourth century, and his little book on the conversion of Constantine is an excellent refutation of many of Burkhardt's exaggerations. Similarly he has done good service in this attempt to define the exact position of Celsus and to reconstruct his polemic, for the first time (as it seems) in a modern language. Though the matter is arranged somewhat out of the order in which an English writer would probably have placed it, the whole is an admirable specimen of clearness and

method. It consists, first, of the text of the aλnons λóyos as quoted or epitomised by Origen, and divided into its four parts in logical sequence. Then follow short essays on two contemporary writers (as Dr. Keim holds them to be), Lucian and Minucius Felix; and thirdly, an analysis of the arguments of Celsus, an estimate of their value and of the historical conclusions to be drawn from them, ending with a discussion of the date of the composition and of the personality of the author.

The importance of the undertaking is obvious when we consider how little we know of the attacks made by cultivated heathens upon Christianity. Besides the satire of Lucian on the death of Peregrinus, we have nothing, except the late and clumsy Philopatris, which has not come down to us in the replies of Christian opponents. Fronto and Porphyry have disappeared, and Hierokles and Julian (like Celsus) have to be reconstructed mainly from the pages of their adversaries. The commonplaces of the controversy can, no doubt, be gathered from the Greek apologists, and in an especially clear manner from the first half of the Octavius of Minucius Felix; but Celsus was, it would seem, an abler champion than those with whom they generally had to deal. He abstained in great measure from the gross and trivial calumnies against the Christian life which were the staple of the vulgar polemics, and really had a system (such as it was) to offer in place of Christianity. He knew something, too, of its relation to Judaism, and he could employ his knowledge of the differences between Jews and Christians, between the Church and the heretics, and between the sects themselves, as potent and destructive arguments. He anticipated, in fact, almost all the modern objections to the doctrines of the Church. It is, therefore, of great importance to read what he had to say in a connected and intelligible form at once popular and trustworthy, and this Dr. Keim enables us to do.

We are also grateful for the new light which is thrown upon some of the difficult questions that surround this subject. The first relates to the general position taken up by Celsus. Three divisions of his polemic are usually recognised:-(1) the attempt to overthrow Christianity from a Jewish point of view, couched in two addresses supposed to be delivered by a Jew to our Lord and his disciples; (2) a general attack from the side of philosophy on the revolutionary character and folly of Christians, and specially on the belief common to them with the Jews of a providential dispensation of which they are the centre; and (3) a particular criticism of doctrines, many of which are explained as misunderstandings of philosophical conclusions. In addition to these Dr. Keim has brought into prominence a fourth part, and that one of great interest, namely, the system which Celsus recommends to Christians in place of their own, and which is contained in the reply of Origen from vii. 62 to the end of the book. The question may indeed be raised whether it was sharply marked off from the preceding part, but there can be no doubt of its logical distinctuess. It is interesting to It is interesting to

note this early appeal to Christians to descend from their position as possessors of absolute truth, and to take their stand among the other religious sects of the world-an appeal heard not indistinctly in our own day, though on somewhat different grounds. Celsus was quite willing to allow Christians to worship the supreme God, if they would not so persistently refuse the respect due to the inferior deities, which he and they alike called by the name of daiμoves. He argues among other things that the doctrine of the Son of God and the worship paid him by Christians, was a step in this direction (Origen viii. 13). He would himself possibly have been ready to accept our Lord as a daipur, though in some Cerinthian or Docetic sense (see viii. 39 cp. v. 2 foll.). The reply of Origen was of course that daiμoves was not an indifferent term, but on Christian lips meant only evil spirits, and that even if there were such beings as Celsus held, they were distinct in kind from God the Word, the Son of God. Yet we cannot be surprised if Celsus expected to receive some acceptance for his theory among the various Gnostic sects, with which he seems to have had more acquaintance than with orthodox Christians. Nor can we fail to sympathise with the yearning after a mythical period when all nations were subject to "one law and one doctrine " which he shares with Maximus Tyrius and Plutarch (see Keim, p. 213).

Of the historical points treated in this essay, the most generally interesting are the date of Minucius Felix and the identification of Celsus with the friend to whom Lucian addressed his life of Alexander the impostor of Abononteichos. Dr. Keim adopts the earlier date assigned to Minucius, which has recently been defended by Ebert, and we think with justice. The question turns chiefly on two points-the relation of the Octavius to Tertullian's apology, and the internal evidence which it affords as to the position of Christianity. Probability certainly inclines to the reign of M. Aurelius rather than that of Alexander Severus. The latter date seems to be based on two misconceptions-a false idea of the originality of Tertullian, and an oversight of those passages of the Octavius which point to an era of persecution, e.g. jam non adorandae sed subeundae cruces. The difference between Tertullian and Minucius is one rather of style than of originality. The quaintness and warmth of the great African is not incompatible with a vast deal of borrowing from his predecessors, Christian and heathen alike. And if he employed the language of Justin, Tatian and Irenacus, why not also that of Minucius? The mention of Fronto seems also much in point. Granted, that he was the well-known rhetorician, the preceptor of M. Aurelius, whose letters were recovered near the beginning of this century, it is much more likely that he should be mentioned by one who was a contemporary than by a writer who lived after Tertullian. From the absolute silence of other authors with respect to his polemic, it is fair to conclude that it was a pamphlet which had its run and then dropped into obscurity. Otherwise, we have to suppose that Tertullian passed over a writing of an author, an

African like himself, which a later writer refers to as an authority worth refuting. Fronto is, in fact, the only opponent whom i Minucius mentions by name, and it is not altogether an improbable conjecture (though not one of Dr. Keim's) that the speech of Caecilius, in his dialogue, is a résumé of his arguments. No doubt there are points of connexion, as Keim has shown, between the statements of Celsus and Caecilius, but their general position differs very decidedly in two important elements-the absence of a philosophical point of view in Caecilius, and the presence of the whole farrago of calum. nies, of which Celsus knows hardly any. thing. One of these calumnies is specially stated to have been propagated by Fronto (Octavius, chaps. ix. and xxxi.), and the absence of a theoretical basis would be quite in harmony with the character of a man who, in his extant letters, now sharply and now plaintively dissuades his royal pupil from philosophical studies as destructive of his taste in rhetoric. But after all we know too little of this production of Fronto's to lay much stress upon this conjecture, especially as it is of no real importance in determining the date of Minucius. There are other arguments for the early date which will be differently estimated by different minds. We do not feel sure that Dr. Keim does not attach too much importance to the use of reges in the plural as indicating the double rule of Aurelius and Verus, and to the hatred of the Roman Empire expressed in chapter xxxvii., as pointing to the persecu tion of the year 177 (p. 156).

The date and personality of Celsus is much more difficult to determine with certainty. The name is a common one, and Origen evidently was doubtful to which of two persons of the name the book was to be assigned. He concluded, on the whole, that it was to be referred to an Epicurean who lived under Hadrian and his successors, and wrote books against magic. If this conclu sion was right, we have a very probable inference that our Celsus is to be identified with the friend of Lucian, who also wrote against magic. But Origen is not quite sure of this identification, for the Celsus against whom he wrote was much more a Platonist than an Epicurean, and almost seems to have believed in the reality of magic, and to have ascribed to its means the miracles of Christ (Origen i. 68). The latter passage, however (which is well worth reading), less conclusive than it appears at first sight. It occurs in the supposed speech of the Jew, and only acknowledges the reality of the miracles for the sake of argument, and in order to degrade them by comparison with those of the impostors of the day. That the Celsus of Origen was an enemy to the yonres is clear from his language about the itine rant prophets of Palestine and Phoenicia (vii. 9, 11, but cp. viii. 48). As to the tra dition which makes him an Epicurean, it may have arisen from his friendship with Lucian, who may well have been familiar with a Platonist of his temper and critical spirit, just as he was with the Stoic Arrian. Nevertheless, the fact remains that the natural inference from the language of Lucian to his friend is, that he was addressing an Epicurean; and this will always be

1

the weak point of the identification. Dr. Keim shows that it is not an absolute neces

sity to draw this inference, and insists very forcibly on the likeness in character between the Celsus of Origen and of Lucian, and on the whole establishes the probability of their being really one. After all, the question is of no great moment, as Celsus cannot well be later than the time of Marcus Aurelius; and we cannot prove that he was earlier. The assumption that Celsus was a contemporary of Origen (made by the author of a book on Supernatural Religion) is based on two very inconclusive arguments. The first is that because Origen did not know much about the personality of Celsus, he did not know whether he was alive or dead; whereas, the fact seems to be that he knew all along that he lived some time previously, but could not find out much about him. The second is that at the close of his book he speaks of Celsus' promised treatise on morality, and asks Ambrosius to find out whether he has fulfilled his promise, and if so to send it, using language which might apply to a contemporary. Perhaps the author referred to has read no more of Origen than he quotes, and is not aware that he speaks of Celsus throughout as a (hypothetically) present antagonist, and generally in the present tense. Otherwise this must be simply termed a piece of special pleading. The discussion of the relation of Celsus to the canon is interesting and instructive, though necessarily tinged by Dr. Keim's views as to the origin of Christianity. Thus he tells us that Celsus' use of Pauline expressions, though not directly drawn from his epistles, shows "in an interesting manner the strong revival of the Pauline doctrine amongst Gnostics and churchmen in the middle of the second century, after Paul had for a considerable time previous been placed under a bushel" (p. 225). This raises, of course, immediately the fundamental question as to the Ebionism of the early Church, which we have to thank Dr. Lightfoot especially for bringing to the test of common sense and historical probability. We are glad, however, to note the statement that "after long and mistrustful criticism it is found necessary to conclude that the Christian writers since the middle of the second century, and especially Justin Martyr, were acquainted with our Gospels" (p. 227). So, again, Dr. Keim asserts that Celsus used all the four Evangelists, and points out several passages, some of which have been before overlooked, in which he distinctly employs St. John (p. 299). He He takes care, of course, to show his own view of the fourth Gospel, which this is not the place to criticise. But with the admissions

of Dr. Keim on the one hand, and of M. Renan on the other, in respect to the history of the Canon, the apologist for the Christian revelation is able greatly to narrow the field of argument.

JOHN WORDSWORTH.

SCIENCE NOTES.

ANTHROPOLOGY.

Natives of New Guinea.-The last number of the Proceedings of the Royal Geographical Society contains an account of the discoveries of H.M.

ship Basilisk, in the year 1874. To the three races of New Guinea already known to inhabit the island-viz., the Papuans on the south, the Arfaks of the mountainous country on the north, and the Malays of the north-west-Captain Moresby has added a fourth by the discovery of another, probably a mixed race of Malays and Papuans, inhabiting the whole of the eastern peninsula of New Guinea in its northern and southern shores, from about 148° longitude to East Cape, which is in 150° 53′ East longitude, and the adjacent archipelago. This race is distinctly Malayan, but differs from the pure Malay in being smaller in stature, coarser in feature, thicker lipped, and having more frizzled hair. They have high cheek bones, their noses are inclined to be aquiline, the eyes dark and beautiful with good eyebrows; many of the men have light hair and a Jewish cast of countenance; they rise to a height of from 5 feet 4 inches to 5 feet 8 inches, and are sinewy though not muscular, slight, graceful, and eel-like in the pliability of their bodies. This race merges into the pure Papuan in the neighbourhood of Cape Possession, where they vary in colour, stature, and feature; and a mixture of habits confirms the idea of a fusion of race. The new race bury their dead in the ground, and build small thatched huts over them. Their houses, like those of the Papuans, are built on piles, and communicate with the ground by means of a pole notched with steps. They are stone mattocks for turning up the soil; they cultirude but successful cultivators of the ground, using vate yams and taro. Cannibalism does not prevail largely among them, though apparently it is not unknown. They are affectionate to their children, but in some cases were willing to barter them for iron axes. They did not keep their women in the background, but allowed them to have a voice in the trading. The men are but slightly tattooed, but the women are tattooed all over in graceful patterns; the women crop their hair short, but the men wear theirs long and frizzled; the men wear a waistcloth only, but the women a short grass petticoat or ti-ti. Unlike the Papuans they possess the art of making pottery. They are better cooks than the Papuans, and boil their food as well as roast and bake it. The Papuans fish only with a hook and line and a barbed spear, but this race make The Papuans use only outrigger canoes, but these fishing-nets with fibres of a small nettle-like plant. have several kinds. They have developed a system of warlike tactics adapted to the weapons they employ, and when Captain Moresby approached them they formed up in two regular lines, the first line armed with missile spears, and the second line with clubs. This is in conformity with the system adopted by all nations similarly armed, and has, result of experience. Upon the whole, they must no doubt, been arrived at independently as the be regarded as a more civilised race than the Papuans. Up to the time of their discovery by the Basilisk, they appear to have had little or no acquaintance with white men.

The Antiquity of Man.-Mr. John Evans, F.R.S., in his anniversary address to the Geological Society, delivered on February 19, and logical Society, delivered on February 19, and since published by the Society, has summed up the evidence on this subject to the pre

sent time. Until within the last two or three years it was generally the received opinion of geologists that the earliest known traces of the occupation of this portion of the globe by man were posterior in time to what is known as the Glacial Period. Since then, however, discoveries have been made which in the opinion of some geologists cast doubt on this limitation of the age of man in Europe. Among these is the discovery of a portion of a human fibula in the Victoria Cave, near Settle, in a deposit overlain by stiff glacial clay containing ice-scratched pebbles. In common with some others Mr. Evans does not regard the age of the clay deposit as conclusively settled, and thinks it possible that it may have been either reconstituted or even accidentally

come

In

redeposited at a later period. Mr. James Geikie, however, arguing on more general grounds, has to the conclusion that the palaeolithic deposits are of preglacial and interglacial age, and do not in any way belong to post-glacial times. If this view could be adopted, there is no doubt that many apparent anomalies would receive a simple and satisfactory explanation; but at Hoxne, Icklingham, Bedford, Ealing, Acton, and elsewhere where implement-bearing gravels occur, they repose on valleys which are cut through the boulder clay, many of the pebbles from which form constituent parts of the palaeolithic gravels, and there can therefore be no doubt that they belong to a period subsequent to the submergence during which the middle and upper glacial beds were deposited. France the Abbé Bourgeois has attempted to carry man back to Lower Miocene times, relying on implements presumed to have been found in beds of the Calcaire de Beauce, at Thenay, near Pontlevoy. He, however, admits that the implements offer a complete identity with those found on the surface; did they, therefore, belong to these beds we should have the remarkable fact that at that remote period, characterised by mammals as distinct from those of the present day as the acerotherium is from the rhinoceros, or the mastodon from the elephant, primeval man was fashioning implements indistinguishable from those of neolithic times. Mr. Evans therefore suspects some possible error of observation as to their occurrence in these beds. But although for the present we seem unable to find any satisfactory evidence of the existence of man in Western Europe before the glacial period, it by no means follows that none such will eventually be found. It must, moreover, never be forgotten that it is not in this part of the world that a naturalist would be led to look for the cradle of the human race. This is far more probably to be sought in a warmer clime, and amidst a more luxurious vegetation, yielding throughout the year some readily available means of subsistence both to man and to animals that would serve him for food.

Psychological Institute.-If the announcement of a new society under this designation were really calculated to promote the scientific study of psychology, it would be hailed with satisfaction by all who are interested in the study of man. perience has proved that the materials for a Such, however, is hardly to be expected. Exseparate psychological society apart from general anthropology, are not forthcoming otherwise than by the admission of matter that is beneath the proper dignity of science. This new institution adds another to the list of nine societies which in London alone deal with anthropological subjects, some of them in an extremely feeble and unsatisusually had a short-lived activity, ending in Such branch societies have factory manner. stagnation; they entail separate apartments, extra salaries to secretaries, and the publication of a vast mass of rubbish in order to maintain an annual volume of Transactions. The same results might be obtained with far greater economy by the formation of special sections under the auspices of a larger society. We can only, therefore, regard the formation of this new society as contributing to the existing disorganisation through which the scientific force of the country is being frittered

away.

PHYSICS.

Electric Conductivity of Lead Compounds.-Buff observed in 1859 that the electric conductivity of chloride of lead increases with the temperature instead of diminishing, as is the case with metallic substances. E. Wiedemann has confirmed this observation (Pogg. Annalen, cliv. p. 318), using the chloride both in the form of compactly pressed powder, and also fused and then solidified. Iodide and bromide of lead possess the same pro

perty. It appears, however, that the conductivity is not quite like that of a metal (as was stated by Buff), for at temperatures considerably below the fusing points of the lead compounds a certain amount of electrolysis takes place, as was shown by the polarisation current when the battery was removed from the circuit and the terminals connected with a galvanometer.

Electric Conductivity of Solutions of the Chlorides of Alkalies and Alkaline Earth Metals.-The researches of Professor Kohlrausch and O. Grotrian on this subject are published in the last two numbers of Poggendorf (cliv. pp. 1 and 215). It was necessary in their experiments to take great care in noting the temperature and preventing or allowing for any changes in temperature, since the conductivity of electrolytes is influenced by temperature in a very high degree. The source of electricity employed was an induction apparatus, called by the authors a Sine-Inductor, and described in the Jubelband (p. 290). A magnetised disc is rotated in a coil of wire with such velocity as to produce from 100 to 200 currents in alternate directions in a second. The object of employing a system of currents in alternate directions is to prevent the polarisation of the electrodes.

For a

The authors have determined the conductivities of aqueous solutions of nitric acid and of the chlorides of sodium, potassium, ammonium, lithium, magnesium, barium, strontium and calcium. Three sets of experiments were made, as nearly as possible at the temperatures 0°, 18°, and 40°. The conductivity of each substance was investigated at each of these temperatures, the strengths of the solutions varying from 5 per cent. of the anhydrous salt up to complete saturation. given percentage strength of the solution, it was found that the conductivity increased very rapidly with the temperature, the rate of increase being not quite uniform, but much more nearly so than might have been expected. For instance, the conductivity of potassium chloride (5 per cent. of salt) which is 421 at 0°, becomes 931 at 40°: this increase is immensely great as compared with that of the electric resistance of a metal or the pressure of a gas. When the temperature remains constant, the conductivities increase continuously with the percentage strength of the solution. The chlorides of calcium and magnesium, however, are exceptions to this rule, the solution of CaCl, having a maximum conducting power when it contains 24 per cent. of salt, and that of MgCl, similarly when it contains 19.8 per cent. Nitric acid of maximum conducting power has a specific gravity 1.1945 (at 17° C.).

vapour

Ebullition of Liquids. In a paper on the theory of ebullition (Ann. de Chim. et de Phys. sér. v. vol. iv., p. 335), Professor Gernez gives an historical résumé at some length of what has hitherto been effected in this direction, and then proceeds with the description of his own new experiments and the views he founds upon them. His experiments go to show that solid bodies, which provoke ebullition in superheated liquids, lose this property when they have been strongly heated; that solid bodies without chemical action on superheated liquids cease to provoke the formation of bubbles of when they have been long used to maintain ebullition; and that such bodies, which have been rendered inactive by being long kept in boiling liquid or by the influence of heat, regain their activity on exposure to the air. He states, also, that bodies whose surface is not in contact with air, or which do not contain air or gas in their interior, are without action on superheated liquids, and that a gaseous atmosphere determines ebullition in a superheated liquid. M. Gernez regards ebullition as an evaporation at the surface of gases introduced into the liquid, an infinitely small quantity of gas being sufficient to maintain ebullition indefinitely. The arrangement of the experiment which was the basis of this conclusion was as follows. A small cupshaped cavity was formed at the end of a glass rod, which was specially cleansed. The little cup

so formed could be made to contain an indefinitely small amount of air, and could be depressed mouth downwards into the liquid. The heat being properly regulated, bubbles of vapour were formed regularly at the mouth of the cup, and there only. Some of these experiments were continued for twenty-four hours, this being rendered possible by the fact that the tube in which the liquid was boiled was of considerable length, so that the vapour was condensed before it left the tube and flowed back, there being thus no waste of liquid. The air could be got rid of by arranging the cup obliquely at the end of the glass tube and then inclining it. As soon as the air escaped ebullition ceased.

Some of the views of M. Gernez are combatted by Mr. C. Tomlinson (Phil. Mag., April). The latter maintains that the inactivity of a glass rod or other solid body introduced into a gaseous solution depends on its being chemically clean. A cage of fine wire gauze was submerged in sodawater, but there was no escape of gas so long as it was chemically clean. When taken out, rolled between the slightly greased hands, and again lowered into the soda-water, the gas escaped from its side in bubbles with an audible noise. Supposing a liquid, at or near its boiling-point, to be constituted like soda-water, Mr. Tomlinson refuses to admit that a solid, such as a glass rod, introduced into a boiling liquid (water for example), becomes covered with bubbles of steam by virtue of the air carried down by the rod. If the rod be unclean (that is, contaminated with a greasy film), the steam-bubbles cover it precisely after the manner of gas-bubbles, because there is adhesion between the steam-bubbles and the film, and not between the water and the film, and hence there is a separation. A chemically clean glass rod has no such action, not because the act of cleaning it deprives it of its adhering air, but because there is perfect adhesion between a vaporous supersaturated solution and a chemically

clean surface.

Specific Heat of Carbon, Boron, and Silicon.

The continuation of Dr. H. F. Weber's researches on the specific heats of the elements carbon, boron, and silicon, some points in which were noticed in the ACADEMY for March 27, is given in this month's number of the Phil. Mag. These elements, which have hitherto formed the most marked exceptions to the law of Dulong and Petit, he has conclusively shown to obey the law when a certain temperature is reached. The values of the specific heats of the elements carbon, boron, and silicon, change with the temperature; these values gradually increase with an increase of temperature until a point is reached at which they are constant. This point is situated at about 600° for carbon and boron, at about 200° for silicon. The specific heat of carbon at 600° is about seven times, that of boron about two-and-a-half times, as great as at -50°. Their final constant values are, for carbon 0:46, for boron 0-50, and for silicon 0.205. The products of these numbers into their atomic weights (12, 11, and 28, respectively) are:

55, 55, and 58,

values which are in keeping with the atomic heats of the metals and of the other non-metals. Dulong and Petit's law may therefore be accepted as binding in the case of all the elements; it must, however, be formulated in a manner slightly differing from that ordinarily laid down. Thus, the specific heats of the solid elements vary with the temperature; nevertheless, for every element there is a point (t°) from which the variation with the specific heat with increasing temperature is entirely insignificant. The product of the atomic weight into the specific heat (estimated at temperatures above t°) is for all the elements a nearly constant number, varying from 5.5 to 6.5.

Spectrum Photographs. In the last number of Poggendorff H. W. Vogel describes a simple apparatus for photographing the spectrum of the sun, or other spectra. He removes the lens from

an ordinary photographic camera, and replaces it by a pocket spectroscope, fitted into the aperture by means of blackened cork. The sun's rays are allowed to fall on the apparatus parallel to the axis of the spectroscope. The lines, though not very sharp, are sufficiently so for many purposes, e.g., for the comparison of absorption spectra.

Spectrum of the Aurora.-In the Philosophical Magazine Mr. J. R. Capron has described the results of comparison of auroral spectra with the spectra of hydrogen, carbon, oxygen, air, phosphoretted hydrogen, and iron. Mr. Capron considers that the conclusion of Angström, that the "moisture in the region of the aurora must be regarded as nil" cannot be maintained. He sums up the present state of our knowledge of the aurora question as follows:-"The yellow-green line, and possibly also the red, are due to phosphorescence or fluores cence; the fainter lines are partly due to the air spectrum, and the remaining bands or lines may be due to phosphorus and iron, the close coinci dences in this latter spectrum with the aurora lines being very striking."

MEETINGS OF SOCIETIES. ENTOMOLOGICAL SOCIETY (Monday, April 5). SIR SIDNEY SMITH SAUNDERS, C.M.G., President, in the Chair.

Mr. W. L. Distant, of West Dulwich, was balloted for and elected a member.

Mr. Jenner Weir exhibited a number of young Mantidae that had emerged from an egg-case received from Cevlon.

Mr. Bond exhibited a specimen of an exotic Locust taken alive at the bottom of a well near Brighton. The species was uncertain.

Mr. Sealy read some notes on the habits of the species of Ornithoptera from the Malabar coast, exhibited at the last meeting. It was closely allied to O. Amphrisius, but there were doubts of of

its identity. The pupa possessed the power causing a sound. He called attention to a peculiarity in the formation of the hind wings of the males, there being a large pouch on the anal margin, filled with fluffy hairs."

Mr. McLachlan read a letter from an Englishman residing in Pueblo, Colorado, U.S., stating that from his experience of the potato beetle, the insect could live on the tubers as well as on the

haulm, and that unless the English authorities took some steps to prevent the importation of potato bulbs, he believed the beetles would soon be in this country.

Mr. M'Lachlan also drew attention to a remark by Lieutenant Carpenter in the Report of the Zoological Collections made in Colorado during the summer of 1873, when he noticed that not a single specimen of the potato beetle was to be found to the west of the Rocky Mountains, though he believed it would be ultimately spread over that region by the agency of the seed, as the insect was of too sluggish a nature to be capable of spreading itself so rapidly by its own instinct; and his belief was further sustained by its continued absence from the Salt Lake basin, occasioned by the cheapness of vegetables in the Mormon settlement rendering the importation of potatoes from Colorado unnecessary.

Mr. Bates believed the distribution of the beetle depended more upon climatic conditions. The native home of the insect was on the eastern

plateaux of the Rocky Mountains, and the climate of the Pacific Coast being more like that of the west coasts of Europe, their faunas also bore a greater resemblance. He believed the absence of the insect from the west of the Rocky Mountains to be caused by the difference of climate, and the

same

cause might be expected to prevent the establishment of the insect in countries like Britain, where the moisture of the atmosphere would probably be fatal to it.

Mr. Edward Saunders communicated the first part of a Synopsis of British Hemiptera (Heteroptera).