such have become known, and still fewer have been considered in this manner. In addition to the above-mentioned result of Ramsay and Young, there claims attention one discovered by the Hungarian physicist Eötvös, according to which the molecular surface energy, as expressed by the product of the capillary constant and the 3rd power of the molecular volume, is shown to be a linear function of the temperature. Since the surface energy stands in closest connection with the energy of interaction, by virtue of which the substance of liquids, in contrast to that of gases, assumes its own proper volume, and to which is accordingly due the characteristic existence of the liquid condition, it becomes at once evident that here certainly a means of access to the theory of the latter is afforded. This means may be expected to lead more rapidly to the goal than the methods hitherto almost exclusively tried, based upon a relation between volume, temperature, and pressure.

The stöchiometry of the liquid organic compounds, founded by Hermann Kopp, has enjoyed likewise a steady development. While the question of the boiling-point seems to be essentially postponed until the general theory of liquids becomes known, yet that of the molecular volumes has reached a stage which already assures the prospect of a successful period of development. The additive scheme, proposed by Kopp as a first approximation, according to which the molecular volume is the sum of the atomic volumes-a scheme whose insufficiency Kopp himself had shown in the case of oxygen-determines only the roughest outlines of the phenomenon in question. Other factors make themselves everywhere felt; as was shown by Kopp for oxygen-that the portion of the molecular volume due to it can assume different values according to the function of this element in the compound, i.e. according to the constitution of the molecule-so the same holds for the other elements. An essential difference between univalent and bivalent elements is, in this respect, not present: ethylene and ethylidene chlorides have different molecular volumes, although they both contain saturated carbon atoms, and, in addition, only univalent elements.

In vain

We must, accordingly, more than ever before, recognize the molecular volume as a constitutive property. This recognition removes at once the firm barrier to which the additive scheme, greatly against the will of its originator, had hardened. had been for so long striven to force the facts into this form; ever and again their living body would not fit upon the wooden cross. Now we see that this undertaking was necessarily in vain we begin to comprehend that methyl alcohol must be more different from ethyl alcohol than ethyl alcohol from propyl alcohol; and that these two, again, must stand in a different relation than do propyl alcohol and butyl alcohol, although each time the " same difference of CH, is at hand-that there are, in short, no two pairs of compounds whose differences are entirely the same.

Now, it is quite dependent upon the nature of the property considered, in what relation the additive foundation stands with the modifying effect of constitution. With the molecular volume the first is comparatively superior; with the boiling points, however, the latter make themselves to the most superficial observation so energetically felt that, since the attempts of Schröder, Löwig, and others, which over fifty years ago failed to carry through the additive scheme for the boiling-points of organic compounds, this line of effort has been definitely given up. The other properties which have been studied fall between these two limits.

This holds especially for the molecular refraction. Just as Buff had earlier shown that "double bound" carbon possesses a greater molecular volume than does saturated carbon, it has been demonstrated by Brühl that a similar relation holds for the molecular refraction. This influence of constitution is, however, not the only one; a similar inference has been shown for oxygen and likewise for chlorine, and it has been repeatedly shown that, even if approximately additive laws be followed among the higher members of homologous series, yet these do not apply for the first members. This is necessarily so, as has already been shown in discussing molecular volumes.

The magnetic rotation is a property of much more strongly marked constitutive character than are molecular volume and molecular refraction. We possess here most excellent inves tigations by Perkin, which have often been found of service in determining questions of constitution.

In relation to the connection between the different properties of substances a fruitful line of thought has been carried out by Philippe-Gaye. As is known, Maxwell had derived a definite

relation between the coefficient of refraction and the dielectric constant, from his wide-reaching speculative investigations, which latter had yielded a complete analogy of the mathematical expressions for electrodynamical and optical action at a distance, together with an approximate equality of the fundamental constants, and which have been finally made fruitful by the brilliant experimental investigations of Hertz. This dielectric constant is in turn, according to an expression due to Clausius, a simple function of that fraction of the total volume of a dielectric which is occupied by the actual material substance (considered as conducting). But this so called true molecular volume is, finally, nothing but the co-volume in the equation of Van der Waals. There is accordingly to be expected a close connection between the critical constants and the molecular refraction, and Guye has shown that the expected connection actually exists.

Although spectrum analysis, with its manifold applications, has for years had almost no rational development, it has recently taken a quite promising start in the stochiometric direction. The theoretical and experimental researches of Balmer, Deslandres, Julius, Rydberg, Kayser and Runge, and others, indicate already that the time is not far distant when there shall be simple and intelligible regularities in this field, which until now has been so overgrown with unfruitful hypotheses. Only upon one point I wish at this opportunity, as a chemist, to direct the attention of the physicists. It is held as an undoubted dogma that at the highest temperatures, as, for example, in the electric light arc, all compounds must be dissociated into their elements. This view is certainly not justified. What we do know about the stability of com pounds is, on the contrary, that all compounds which are formed with absorption of heat become more stable with rising temperature, and the reverse. Because the majority of the compounds known to us are formed from the elements with evolution of heat, and correspondingly become more unstable with rising temperature, the conclusion has been drawn that this is in general the case. But if we reflect that cyanogen and acetylene, two compounds formed with great absorption of energy, are readily formed in quantity, at the highest temperatures, in the blast furnace and in the Davy are light, we become conscious that the spectra occurring at high temperatures may, under proper conditions, belong to compounds which, formedu with great absorption of energy, may have a fleeting existence con. fined to those temperatures only. From this point of view, many difficult facts of spectroscopy and spectrometry would have some prospect of a proper interpretation.

At the extreme boundary of the optical properties, towards the side of the constitutive character, stand finally colour and rotation of the plane of polarized light. Although the first property is decisive for one of the most important branches of technical chemistry, the dye-stuff industry, still but little is known as yet about the connection of colour with composition and constitution. The investigations of Krüss, Liebermann, and more recently Vogel, all indicate that the property is in great measure constitutive, becoming additive only within the narrowest limits of closely-related compounds. This renders correspondingly difficult a recognition of the connections at hand. Some time later, on the contrary, directly on account of this marked constitutive character, the colour will be an im portant aid in the determination of constitution; at the same time, when we shall have learned to recognize this connection with some certainty, the discovery of new dyes with definite properties will be no longer a matter of a lucky hand and of an unconscious feeling for this connection, but will rest upon just as broad a basis as, for example, the technic of the metallurgical processes.

The constitutive character of the rotation of the plane of polarization has been always known and recognized. Since van't Hoff and Le Bel, twelve years ago, pointed out the connection between this property and the presence of an "asymmetrical' carbon atom, i.e. one joined with four different elements or groups, this idea has, at first slowly, then more and more rapidly, had an important development. For the "optical symmetry" shown by Pasteur in the tartaric acids, the examples have become more and more numerous; the researches of Wallach on the ethereal oils have especially furnished valuable material. The presence of optical activity is now held as an entirely undoubted proof for the presence of asymmetrical carbon, and Le Bel has just announced that he has succeeded in the preparation of optically active nitrogen compounds containing an asymmetrical nitrogen atom.

The investigator whom we have already mentioned, Philippe

Guye, has made a remarkable attempt to find laws for the nun.erical values of the molecular rotation, by giving to the asymmetry of the carbon atom a numerical measure dependent upon the masses joined thereto, and, in cases of analogous compounds, comparing this with the values for the molecular compounds. While this attempt has been well supported by a number of older measurements, especially those of Pictet on the esters of the tartaric acids, yet his own determinations on the active amyl derivatives have not indeed furnished much very favourable evidence. He has not overcome the difficulties of obtaining pure material, and certain facts were observed contradicting the assumption that the sense of the asymmetry is due to the masses added. It is not improbable that this difficulty will be overcome by placing the optical moment, if I may be allowed the expression, not proportional simply to the mass of the atom; there is rather to be suspected a connection with the atomic refraction.

We turn now to a field whose development belongs entirely to the last few years, to that of solutions. If we call to mind the old saying, Cerfora non agunt nisi fluida, vel soluta, we perceive at once the very great importance of the field; all rational knowledge of chemical processes must be preceded by a corresponding knowledge of the condition of dissolved substances.

I do not need to remind you that van 't Hoff's discovery of the identity of the laws of gases with those of dissolved substances, is to be characterized as the greatest step forward which has been made in this direction. If we reflect that the development of the molecular idea, which rules the chemistry of to-day, is most decidedly based upon the laws of gases in their simple form, we recognize at once that all the important relations which have been here found can be directly transferred to the domain of solutions. The latter has, however, at the same time, far more varied possibilities in the form of its phenomena. While in the case of gases only two of the variables, pressure, volume, and temperature, are independent, there is present for solutions the manifold infinity of the non-miscible and partially miscible solvents. To this is due the appearance of a great number of new formal and numerical relations for solutions, even under assumption of the simplest form of the governing laws, whereby a rich field of inexhaustible fruitfulness is made accessible to investigation. In fact, after this advance by van 't Hoff, the theoretical investigations of Planck, Riecke, Lorenz, van der Waals, and Boltzmann, as well as the progressive combination of theory and experiment by Nernst, have shown how varied and valuable are the results to be gained, results whose details I am here compelled to omit.

I wish, at this opportunity, to call attention to one particular point. I have already mentioned that the way to a rational theory of the liquid condition leads from the gases, through their variation from the simple gas laws, and through the critical point, whose constants express in especially simple form the individual properties of the kind of matter in question. Now it is to be expected from the theory of solutions, and it has been demonstrated in detail by O. Masson and W. Ramsay, that upon transition from a dilute to a concentrated solution we observe entirely the same phenomena that appear when the volume of a gas is diminished; there is here also a critical state with its corresponding constants. We thus have here a second way to a theory of the condition of pure liquids, which, by reason of the greater variety of the phenomena, is a far more difficult one than is that first named, but which, however, may in many cases be of assistance where the other fails.

While the already discussed parts of the newly-opened territory are mainly those problems with which physicists have concerned themselves, still its study has not been less fruitful for chemistry in particular, especially for organic chemistry. To the above-mentioned variety of the relations here present corresponds an equal variety of the methods of determination of that most important constant, the so-called molecular weight of dissolved substances. Since the tireless Raoult had shown years ago, in a purely empirical manner, the application of the properties of solutions to this purpose, it was reserved for the theory of van 't Hoff to discover the rational basis of these relations, and thus for the first time to give to wider circles of investigators a feeling of security in the making of such molecular weight determinations. Especial service has been rendered by E. Beckmann in the technical development of these methods; and the Beckmann freezing apparatus and boiling apparatus form at present just as necessary and much used a part of the equipment

of a laboratory as formerly the Hofmann apparatus for determining vapcur densities.

for

It has naturally come to pass that, together with the suddenly increased range of molecular weight determinations, our views of the nature of this quantity and of the therewith connected question of valence have undergone a corresponding change. The conception had become gradually rather dogmatically rigid: it was understood to require for each substance only a single absolute molecular weight, the variations observed, example, in the case of acetic acid, being characterized as anomalies. Molecular weight determinations in solutions have shown that such variations are so extended, and, at the same time, occur so regularly, that they may no longer be pushed aside as anomalies. It is therefore at present generally recognized that a substance may quite well have different molecular weights, standing in the ratio of simple multiples, the most important weight for the chemist being of course the smallest of them.

The consequences connected with van 't Hoff's discovery being so important and wide-reaching, they have had in general a friendly receptior, although a few scientific men-not of the highest rank-fearing the little plants cultivated by them to be endangered by the flood of light falling upon them, have attempted a slight resistance. On the contrary, all the uneasiness which is unavoidably connected with important revolutions has been directed against a second idea, which, appearing somewhat later than that of van 't Hoff, removed a fundamental difficulty in the theory of solutions, which had until that time made its acceptance impossible for me. This idea has at the same time shown itself as an aid to investigation to be of unexampled sweep and value. This is the theory of electrolytic dissociation, of Arrhenius.

It is certainly to be presumed that the fundamental idea of this theory is generally known. In the aqueous solutions of the electrolytes, the salts, acids, and bases, a greater or less proportion of the dissolved molecules are regarded as split up into electrically charged constituents or ions, which exist in the solution indepently of one another in the same manner as the partial molecules of a dissociated gas. If the van 't Hoff theory be admitted, it must be admitted that in a solution of sodium chloride, for example, almost double as many individual particles or molecules are present as in a corresponding solution of sugar or urea of the same formula weight. The experimental connection of these variations with the fact and numerical amount of the electrical conductivity, first discovered by Arrhenius, and which cannot be denied, furnishes the basis for the second part of the theory of Arrhenius, the assumption of electric charges upon the separated molecular constituents or ions. If now these fundamental ideas are accredited, the remainder follows with directly evident necessity.

The significance of these views becomes apparent upon considering the quite astonishing range of phenomena in the most widely separated parts of physics and chemistry which have received explanation from the theory of Arrhenius in connection with that of van 't Hoff. It is simply impossible in the limits of this address to even enumerate these single applications; I shall, as I think, do better by treating the question from a more general standpoint, and, without speaking in particular of each advance made, sketch in rough outline that field in which both theories have brought or will bring decisive explanation.

Let it be first called to mind that the laws of dissociation were already earlier derived thermodynamically for gases. If, then, in the field covered by Arrhenius, the question be one of dissociation, and the laws of gases do, according to van 't Hoff, hold for dissolved substances, it follows that the entire theory of the chemical affinity of electrolytes must be yielded by the applica tion of those laws of dissociation. This means nothing less than that the problem of chemical affinity is in reality solved.

The conception of chemical affinity is to be understood to reach so far as to include all phenomena caused by the so-called inner energy of bodies. It includes, then, not only the processes especially termed chemical, but also those of vaporization and solution without exception as well. If it be wished in the latter case to preserve the ever emphasized but still unclear distinction between "chemical" and "physical" processes, to the former may be reckoned those processes in which electrolytic dissociation comes into question, and to the latter those in which this is not the case. Thus, the dissolving of oxygen in water is in this sense a 46 physical," that of hydrochloric acid in water a "chemical," process. But this distinction is secondary: it is expressed only in the greater complication of the corresponding

formule; the fundamental equations remain everywhere the same. In other words, the question is one of the theory of all conditions whereby heterogeneous substances or heterogeneous phases of the same substance have assumed, after reciprocal influence, a condition of equilibrium independent of the time.

The general theory of these conditions has been developed by J. Willard Gibbs sixteen years ago; a German edition of this magnificent and incredibly many-sided investigation is at present in the press. Through van 't Hoff and Arrhenius we are placed in a position to insert in the equations of this man of science, which contain necessarily a great number of yet unknown functions, the expressions for these functions, together with the numerical constants, and to thus solve the problem numerically from case

to case.

It must, however, be borne in mind that the functions in question, expressing as the sum of its single forms the total energy of the system considered, are yet known only for the cases of gases and dilute solutions, i.e. for the cases where the inner energy has become independent of the volume. As far as the knowledge of the equation of condition reaches, extends the possibility of mastering the heterogeneous conditions and chemical equilibria. And we see at this place how the different parts of general chemistry reach to one another the hand; the solution of the problems which were mentioned in the first part of this address is also, for that just discussed, the unavoidable condition of progress.

But with the range just measured off, great as it is, the limits of the province of the van 't Hoff-Arrhenius theory are not yet reached. The dissociation discovered by Arrhenius is an electrolytic one. Accordingly, the immense number of phenomena, in which the electrically charged ions participate, belong likewise with those which here receive a new light. The question as to the source and maintenance of the electrical energy in the galvanic elements, as to the conduction of current in electrolytes, as to the meaning of galvanic polarization, are only single points in this field. Electro-chemistry in the widest sense, and, indeed, as much so that part which is concerned with essentially electrical questions as that which studies chemical questions, has already received most valuable furtherance from our theory, and has yet more in prospect.

It is natural, as against this exposition, to propose the question how the theory of van 't Hoff and Arrhenius has responded to the requirements which have been made upon it in a so extraordinarily wide-reaching and varied manner. Since I belong to the few who make use of this aid in their investigations, I must freely confess that my judgment in this matter may be looked upon as subjective; but since, on the other hand, I hold to both theories unfortunately, not the position of a father, but only that of an uncle of rather distant relationship, you may trust me that at the time of first meeting them I was rather inclined to repel than to greet them. I can then only personally declare that no scientific idea produced in my time has assisted me in such measure as has this one, and that I have further gained the impression that the great scientific fields named have received likewise unusual furtherance from this idea. In particular the extraordinarily manifold and severe test which lies in the numberless numerical eonsequences of the theory in all possible fields, has yielded such a number of confirmations that the relatively rare cases where the unprejudiced decision was "insufficient" entirely vanish. Naturally must not be considered the judgment of those who, with insufficient qualifications, set themselves up as judges, who do not attempt to test the theory, but only to refute it. The misunderstanding and false conceptions from which such refutations proceeded have been in fact of such kind that thereout no real progress, which is the end of every scientific undertaking, has resulted.

66

I hasten to close. The concise review of the working ground of general chemistry, which I have just attempted to give, shows to what great extent chemistry has made use of physical means to solve her problems. It is, therefore, not especially necessary to urge my chemical associates that they should follow up the study of physics and acquire the necessary mathematical knowledge. It is cared for at many Universities by the more far-seeing teachers of chemistry, that this indispensable knowledge is made as accessible as possible to our youths, and my personal experience has shown me that such opportunities are gladly and profitably used.

But the reverse does not present so favourable an aspect. The science of physics requires for its extension and development exhaustive chemical knowledge in many directions. All

phenomena in which the special character of matter comes into question require for their study an extended knowledge of just this character, i.e. chemical knowledge. And I cannot avoid complaining that in this direction too little is done. In the more recent physical literature, I have met not seldom chemical views, which were, in short, fearful, and which gave to the interpretation of the observed phenomena an entirely false direction. The physicist is only too inclined to consider chemistry as an inferior science, of which he knows a great sufficiency if, in the early part of his student life, he has once heard its lectures. Nothing can be more wrong than such a view. By reason of its richer and more special store of facts, chemistry really remains behind physics in its development into a rational science, and it will ever so remain, in the same way as physics remains behind astronomy or mathematics. But directly for this reason the beginning of the student years is the only time in which to become acquainted with the varied details of chemical phenomena, and to take up the enormous range of experience here offered. For, according to experience, the physicist never learns them later. The history of our science points out a number of men, who, from chemists, have become physicists of high rank; I need name only Regnault, Faraday, Davy, Magnus, Hittorf. But I cannot name a single man of science who, after having been trained as a physicist, has made one purely chemical discovery of importance, for it never occurs that a physicist later learns chemistry. The great range of empirical experience can only be incorporated into the memory at a time when the latter is fresh, and it is usually already too late but a few semesters after the student life has been begun.

I can, therefore, not urge my physical colleagues enough: send your students at first for a few semesters into the chemical laboratory. We chemists must indeed do our part, in suitably rearranging the laboratory instruction; the practice in qualitative analysis should, in particular, be greatly cut down, and in its place preparative work in its widest sense, together with the typical forms of quantitative analysis, should be taken up. But since the same requirements are to be made upon the education of the future teacher of the natural sciences and mathematics in the Gymnasia and Realschulen, it will not be difficult to soon find the methods best adapted for the chemical education of all non-chemists, without injuring the immediate purpose of the chemical laboratories-the training of chemical specialists.

THE GENERAL CIRCULATION OF THE

ATMOSPHERE.

IF the question of the general circulation of the atmosphere were referred to a meeting of educated people, one might be sure that ninety out of a hundred who could give any answer at all would explain it by the time-honoured equatorial and polar current; if anyone initiated in the subject sat near, one would observe a pitying smile upon his lips, and, if asked for his opinion, he would relegate that current, of sacred memory, to the region of the fables, or at most only allow it to hold sway, with certain limitations, in the tropical and sub-tropical zones, the region of the trade-winds; the temperate and cold zones however would be reserved for the dominion of the variable winds, and of newly arisen cyclones and anticyclones, of which we cannot tell whence they come and whither they go, i.e. for the origin and disappearance of which we cannot lay down any laws. And if there were several of these initiated persons present, a discussion would at once occur, from which no one could obtain a clear idea, and which would leave everyone with the impression that nothing certain was known about the subject. I suppose that you have been present at such a discussion, and have appealed to me to explain to you the present state of our knowledge of this subject.

I undertake this task the more willingly, since the question of the general circulation of the atmosphere has but recently entered upon a new stage, which marks a great step towards the complete solution of the question, and becanse it is very desirable to obtain as wide a diffusion as possible for this theory which corresponds to the present state of the science.

In this question especially, as in many others, the history of the development is exceedingly instructive, and of the greatest value in aiding a comprehension of the subject. I propose, therefore, that you should follow me through the different stages Translation of a lecture delivered by Dr. J. M. Pernter before the Scientific Club in Vienna.

Parliament. Of the Parliamentary grant no less than £164,437 went to the North-West, including Manitoba and Keewatin; while British Columbia took £17,010 of the remainder.

THERE seems to be no doubt that the aborigines of the Andaman Islands are rapidly disappearing. According to the latest administrative report relating to the islands, all the people of Rutland Island and Port Campbell are dead, and few remain in the South Andamans. Mr. Portman thinks that the present generation of this interesting race will be the last. Only a small number of children are born, and they do not survive infancy.

IN his Presidential address to the American National Geo graphic Society, now printed in the Society's Magazine, Mr. Gardiner G. Hubbard presents an interesting sketch of the forces which have been at work in the evolution of commerce. In the concluding passage he glances at what he supposes to be the future of commerce. America, the last of the continents to be inhabitated, now receives, he points out, the wealth of Asia on the one hand and manufactures and population from Europe on the other. "Here the East and West, different from each other in mental power and civilization, will meet, each alone incomplete, each essential to the fullest and most symmetrical development of the other. Here will be the great banking and commercial houses of the world, the centre of business, wealth, and population."

IN ancient times Greece possessed something like seven and a half millions of acres of dense forest, and she was comparatively rich in timber until half a century ago. Many forests have now disappeared, and the result is seen both in the scarcity of the water supply and in various injurious climatic effects. The Austro-Hungarian Consul at Athens-while calling attention to these facts in a recent report, of which some account is given in the Board of Trade Journal for April-points out that even at the present day Greece possesses about two millions of acres of forest land. The quantities (in cubic metres) of timber and forest produce obtained in 1890, compared with 1889, were : building wood, 59,948 and 48,986; timber for shipbuilding, 2606 and 1640; for tools and machinery, 4146 and 2940; lignite, 509,895 metric centners, compared with 466,953; asbestos, 491,722 metric centners, compared with 490, 179; and tanners' tawing materials, 20,003 metric centners, compared with 30,089 in 1889. Notwithstanding this considerabie production, Greece will have to import large quantities of timber in the near future, so as to meet the demand arising from the revival of the building trades now affecting both the rural and urban districts of the peninsula.

A PAPER on the agricultural needs of India, by Dr. J. Augustus Voelcker, was read the other evening before the Society of Arts, and is printed in the current number of the Society's Journal. It gave rise to an instructive discussion, in the course of which Mr. Thiselton-Dyer-referring to the necessity of India producing sufficient food for its growing population-said the real question was how to get more nitrogen into the soil. That overshadowed everything else. He agreed with Prof. Wallace, who had spoken before him, as to one way of supplying this want. After the studies made in Germany, France, and England, there could be no longer any doubt that the growing of leguminous crops did enrich the soil with nitrogen in a way which, as far as was at present known, without manure, could be done in no other way; but in India the method of green soiling was not altogether unknown. If it were, the sooner some popular account of the method was distributed the better. An old pupil of his own, who had charge for a time of an experimental farm at Bangalore, found that by making some slight addition to the Indian plough he was able to stir the soil-not to plough

deeply, but to stir it lower than the ordinary plough did, and, by slightly opening the subsoil in this way, the roots were able to get down lower, and the crops, even in a season of drought, flourished in a way they did not when the soil was cultivated in the ordinary manner. He was inclined to think that the Indian plough was a thing which deserved a good deal of study; but it could not be studied very well by people in Europe, because our conditions were so different. The study should be made on the spot, and efforts should be made to improve the agricultural methods there by the introduction, if possible, of some kind of rotation with leguminous crops. He was under the impression that, in a great deal of the cultivated land of India, there was something like a pan, formed at no great distance below the surface, which made it extremely difficult for the roots to penetrate, and so they were unable to bear even a slight drought.

THE Great Bower Bird seems to give the people of Northern Queensland very frequent occasion to think about him. Every kind of fruit suffers from his depredations; and, according to a letter from Mr. E. M. Cornwall, printed in the Victoria Naturalist, he has also a taste for new-laid eggs. Says Mr. Cornwall :-"This is not mere supposition, but hard fact, for after noticing the disappearance of eggs in a most unaccountable manner for some time, the gardener kept watch, and was rewarded by seeing Mr. Bower Bird fly straight to a nest just vacated by a hen and deliberately pick the egg and polish off its contents." "In re the Great Bower Bird. Since writing you last, I have had still further evidence to convict this rogue of what I charged him with. A bird was seen to fly right to a hen's nest in an empty shed and immediately emerge with an egg in his long claws; but the egg proved an awkward burden, and he dropped it ere he had gone many yards."

COLONEL W. S. HORE gives in the journal of the Bombay Natural History Society (vol. vi., No. 3) an interesting account of the taming of a heron. Writing from Deesa in September 1891, he says that during the then recent monsoon a young egret or heron with a greenish-brown neck and body, white-tipped wings, and green legs, flew into the verandah of his house, apparently in search of food. He caught it, and for about ten days kept it under a large basket, feeding it with raw meat. He then gave it its liberty, but it refused to leave. It grew very tame, and would feed out of Colonel Hore's hand. Occasionally it would indulge in a bath in one of the dog's tins, and afterwards sit on a chair in the verandah. In the evening it flew away to roost in one of the large neem trees in the compound. It showed no fear of the dogs, and would give any of them who came too near a vigorous "dig" with its long bill. It remained with Colonel Hore for about six weeks, when, as his regiment was under orders to march, and he was afraid if left behind it would meet with an untimely end, he carried it down to the river about two miles off and left it there.

THE new number of Petermann's Mitteilungen has a map of the Kalahari Desert, and the western part of British Bechuanaland, with remarks by Edward Wilkinson. There are also articles on the Pamir question (with map), by F. Immanuel, and contributions to our knowledge of the south-eastern part of Persia, by A. J. Ceyp.

THE Rochester Academy of Science, U.S., has published two brochures of the first volume of its Proceedings. The papers are attractively printed and well illustrated. Among the contributions we may note "The Aurora," "The Forces concerned in the Development of Storms,' and "The Zodiacal Light," by M. A. Veeder; "Description of New Meteorites,” and "Notice of a New Meteorite from Louisa County, Va.," by Edwin E. Howell; "Root Foods of the Seneca Indians," by G. H. Harris; "Descriptions of New Species of Muricidæ, with remarks on the apices of certain forms," by Frank C.