efforts by accumulation became prominent, and simple weariness passes into what was called "distress." Here the result depended not so much on the direct effects of the work on the parts which were actively employed, not so much on the changes wrought in the muscles or in the nervous machinery at work, as on the success with which other members of the body came to the aid of those actually engaged in labour. The internal life of the body, no less than the external life, was a struggle for existence, a struggle between the several members, a struggle the arena of which was the blood. And it would seem that the onset of distress was chiefly determined by the failure of the organs to keep the blood adequately pure. Something depended on the vigour of the muscles themselves, something on the breathing power of the individual, something also on the readiness with which the heart responded to the greater strain upon it; but beyond and above all these was the readiness with which the internal scavengers freed the blood from the poison which the muscles were pouring into it. Undue exertion was exertion in which the muscles worked too fast for the rest of the body. The hunted hare died not because he was choked for want of breath, not because his heart stood still, its store of energy having given out, but because a poisoned blood poisoned his brain and his whole body. So also the schoolboy, urged by pride to go on running beyond the earlier symptoms of distress, struggled on until the adequate commercial return could be expected from such a survey, for new fishing grounds might be discovered. To carry on this work, the present Government Grant of £1000 a year, received by the Marine Biological Association, ought to be trebled, and a grant of £5000 should be made for a deep-sea vessel. Dr. Günther expressed the opinion that hatcheries should be established for the protection and extended cultivation of sea-fish, and Mr. Holt testified to the considerable depletion of the fisheries in the North Sea, to prevent which a size-limit for different kinds of fish was recommended, rather than an absolute close-time of four months in the year. A PHOTOGRAPHIC exhibition usually includes mechanical appliances and improved outfits specially designed to catch the cye of the artless amateur photographer. But there is to be a new departure in this, as in many other customs. In October next an exhibition of photographic pictures, to be called the "Photographic Salon," will be held at the Dudley Gallery, Piccadilly, and it will be concerned, wholly and solely, with photographs of pictorial merit, leaving the means by which such results can be obtained to be otherwise advertised. Those who desire to have their pictures hung in this academy of photographic art should communicate with the secretary before the beginning of September. A NUMBER of lectures will be delivered in connection with the Gilchrist Trust, from September to December, in the Great Assembly Hall, Bethnal Green. Prof. V. B. Lewes will open the series with a lecture on "The Atmosphere and its Relation to Life." He will be followed by Sir Robert Ball, on "Other Worlds," Dr. Andrew Wilson on "The Brain and Nerves," the Rev. Dr. Dallinger on "Spiders: their Work and their Wisdom," and Dr. J. A. Fleming on 'Magnets and Electric Currents." 66 LOVERS of the piscatorial art will welcome the suggestion that the 300th anniversary of the birth of Izaak Walton, on August 9, shall be commemorated by some memorial. There is a marble bust of Walton at his birthplace, Stafford, and statue at Winchester, where he is buried, but in heaped up poison deadened his brain, and he fell dazed and giddy, as in a fit, rising again, it might be, and stumbling on unconscious, or half conscious only, by mere mechanical inertia of his nervous system, falling once more, poisoned by poisons of his own making. All our knowledge went to show that the work of the brain, like the work of the muscles, was accompanied by chemical change, and that the chemical changes were of the same order in the brain as in the muscle. If an adequate stream of pure blood were necessary for the life of the muscle, equally true, perhaps even more true, was this of the brain. Moreover, the struggle for existence had brought to the front a brain ever ready to outrun its more humble helpmates, and even in the best-regulated economy the period of London, the home of his adoption, his claim to have his most effective work between the moment when all the complex machinery has been got into working order and the moment when weariness began to tell was bounded by all too narrow limits. If there were any truth in what he had laid before them, the sound way to extend those limits was not so much to render the brain more agile as to encourage the humbler helpmates, so that their more efficient cooperation might defer the onset of weariness. NOTES. FROM the Times we learn that a volcanic outbreak has occurred at Fukushima, in Northern Japan. Large volumes of dust and vapour have been emitted, and the country for miles around has been covered with volcanic ash. Landslips of great extent have occurred in the same neighbourhood, and are supposed to be caused by the volcanic action. DR. H. J. JOHNSTON-LAVIS sends us the following informa tion:-After many years in which the crater of Etna has been in a solfataric state lava has again risen, and now occupies it. This is a very rare condition of things in that volcano. Earthquakes continue in the north of Sicily, but on the flanks of Etna there is marked quiescence, which might be expected when the main chimney is free. ON June 13 a select committee of the House of Commons resumed the hearing of evidence in connection with sea fisheries. Prof. Ray Lankester urged that a proper survey should be instituted round the coasts, in order to ascertain the movements and habits of fish in the areas resorted to by fishermen. An a name and work written on a memorial tablet has hitherto AN international anthropometrical congress will be held at Chicago, from August 28 to September 2, under the auspices of the World's Congress Auxiliary of the Columbian Exposition. It is requested that the titles and abstracts of papers on anthropology be forwarded as early as possible to Prof. C. Staniland Wake, Department of Ethnology, in order that the programme may be arranged. MR. A. O. WALKER informs us that about 8.15 p.m. on June 15, three shocks in rapid succession were felt at Colwyn Bay. The shocks present the characteristic features of true earthquakes, but evidence from a wider area is required to decide the question. THE thunderstorms which occurred in some parts of our islands about the middle of last week were accompanied generally by very little rain; in parts of Kent, for instance, the total rainfall since the beginning of March has only amounted to about three-quarters of an inch, or 13 per cent. of the normal amount. The temperatures have been exceptionally high, the maxima ranging from 80° to 88° in many parts of the kingdom, while on Monday the 19th instant, the temperature reached 91° at Greenwich. This is the highest reading which has occurred there in June since the year 1858, and it has not been exceeded in any part of the summer during the last five years. In the early part of the present week shallow depressions passed over these islands causing the recurrence of thunderstorms in many parts. These were accompanied by smart showers in a few places, and by a considerable fall in the temperature, the maximum in London on Tuesday being 24° lower than on the previous day. The Weekly Weather Report of the 17th inst. showed that the mean excess of temperature ranged from 3° or 4° in England, to 6° in Scotland, and to 7° in the north of Ireland. There was no rainfall whatever over the greater part of England and Scotland. THE Vatican Observatory has issued the third volume of its Pubblicazioni, containing xxiii + 442 quarto pages and thirty plates. The plan followed by Padre Denza is the same as in the previous volumes, and the work is produced in the same excellent style. After quoting some historical documents relating to the observatory, an account is given of the last general meeting of the superintending Council and of the principal astronomical and astrographic researches carried on at the observatory. Although the magnetical and geodynamical sections are not yet in order, several papers of special interest in these important subjects are published. The meteorological section contains hourly observations and results for the year 1891; in this branch we specially notice a paper on the classification of clouds by Sr. F. Mannucci, photographic assistant at the observatory, illustrated by fourteen photographs taken at the observatory and neatly printed by Dujardin of Paris. The classification adopted is that proposed by Messrs. Abercromby and Hildebrandsson, and consists of ten different kinds of clouds, divided into five principal groups, according to the heights at which the various forms are usually found. The last part of the work contains an account of the proceedings of the ordinary meetings held in the year 1892. PROBABLY few people are aware that there still exists in this country a manufactory of gun and tinder-box flints, yet such is the case. Mr. Edward Lovett, in the Illustrated Archeologist for June, gives an interesting description of the flint industry which has been carried on at Brandon, situated on the borders of Suffolk and Norfolk, since the Stone Age. The methods employed in the mining and fashioning of flints at that remote period prevail, with little alteration, unto this day. In order to break flint into pieces of convenient size, the worker places the mass on his knee, and, by a dexterous blow with a hammer, shivers it into fragments as easily as if it were chocolate. The pieces are then split into flakes, and these, in turn, are fractured into little squares which, with very slight trimming, become the finished gun-flints. Most of the gun-flints are exported to Zanzibar and other ports in communication with the interior of Africa, but, besides these, large quantities of flints for tinderboxes are still made at Brandon. Tinder-box flints chiefly go to Spain and Italy for use in isolated districts. It is a curious fact, however, that the flint-and-steel method employed by prehistoric man in making fire is better than matches in uncivilised regions, and very moist climates. AT a recent meeting of the Société Française de Physique a note from Dr. Stephane Leduc was read, in which the correspondant points out that the physiological effects of alternating currents obtained from electrostatic machines are very different to those up to now observed with ordinary alternating currents of high tension and frequency. Thus, if the terminals are held in the hands nothing is felt, although a continuous stream of sparks is passing between the dischargers. If, however, the current is localised at one point on the skin by [JUNE 22, 1893 means of a rounded point, directly this point passes over a nerve, either sensory or motor, the nerve is excited throughout all its length beyond the electrode. The sensation felt in the sensory nerves allows of their distribution being accurately fol. lowed, while the least displacement of the electrode on the surface of the skin causes a cessation of all these effects. These currents can in this way be used to localise the seat of nervous excitation with much greater accuracy than has been hitherto possible. the capacity of polarisation have been confirmed by some recent THE results obtained by Blondlot in his extensive research on experiments of M. Bouty (see Proceedings of the Société Française de Physique). M. Bouty has chiefly studied the case of melted electrolytes, of extremely dilute solutions of salts and of solid electrolytes, and his results have very conclusively shown that the initial capacity of polarisation (K) is independent of the direction of the polarising current. When a platinum electrode has been immersed in a melted electrolyte for twenty-four hours it possesses, for a given temperature, a constant initial capacity of polarisation, which increases rapidly with tempera ture, while the maximum polarisation decreases. In the case of (those of platinum excepted) the value of K is very nearly the electrodes of platinum in concentrated solutions of most salts same for all, and varies little on account of dilution, while there appears to be no connection between the value of K and the specific resistance of the solution. A CURIOUS optical illusion is described by M. Bourdon in the Revue Philosophique. If an object moves before our eye, kept fixed, it undergoes, in passing from direct to indirect vision, an obscuration, a change of coloration; and the opposite effect occurs when the object comes into the field of direct vision. It is natural to suppose that this plays a part in the perception of motion, and one fact proving that it does so is, that if we render a slow-moving object suddenly invisible, e.g. by means of a shadow, its velocity of displacement seems much increased. M. Bourdon describes an arrangement in which a long pendulum with white thread is swung from a cross bar on a vertical support, which is illuminated from a lamp, while a screen is introduced to give a shadow (the order being, observer, lamp, screen, vertical support, pendulum, dark wall). The white thread in its swing passes into the shadow of the rod and screen, and each time it enters or reappears its velocity seems increased considerably. It seems as if attracted into the shadow, and as if it entered into the light with a sudden shock. It is necessary that the thread should cease to be visible when it enters the shadow. With a red thread the illusion also occurs, perhaps somewhat less vividly. A simpler plan than the above is to hang a pendulum from the ceiling, shading with a screen. A NEW method of determining the hardness, or rather perhaps the friability of substances, has been described by Hr. August Rosiwal at a meeting of the Vienna Academy. The measurements consist in comparing the losses of weight sustained by the bodies under investigation by scratching them with a given weight of polishing material mounted on a metallic or glass base until the material loses its efficiency. The polishing materials used were dolomitic sand, emery, and pure corundum. The diamond was assigned its place in the scale of hardness by comparing its efficiency as a polishing material with that of corundum. It was found to be 140 times as hard as corundum. Tested by this method, the constituents of Mohs's scale have the following numerical values:-Diamond 140,000, corundum 1000, topaz 194, quartz 175, adularia 59'2, apatite 8o, fluorspar 6'4, calcite 56, rocksalt 2'0, and talc o'04. The great advantage of the method consists in the ease with which the hardness of mixtures of minerals in the various rocks is determined. PROF. OBERBECK, of Greifswald, has been studying the spreading of oil on liquid surfaces on a larger scale than that of ordinary laboratory work. The experiments, which are described in the current number of Wiedemann's Annalen, were carried out in the Bay of Rügen, upon which the Prussian university town is situated. The professor sailed out into the bay for a distance of 2 km. or so, accompanied by an experienced mariner, and armed with bottles holding from one-tenth to half a litre of machine oil or rape-seed oil in measured quantities. Sitting in the stern of the vessel, he poured the contents of the bottles at intervals into the water in a thin continuous stream, the vessel meanwhile moving at a uniform rate in the same direction. After about an hour the oiled tracks were revisited. The brilliant colouring had disappeared, and the oil had spread out into well defined rectangular light-grey patches, easily distinguished from the rest of the sea by the absence of ripples and their consequent superior reflecting power. Their area was estimated, with the aid of the experienced mariner, by the time occupied in sailing past. In the case of the half-litre bottle the patch measured 300 by 30 metres, thus giving an area of 18,000 square metres corresponding to one litre of oil. A more accurate measurement was made subsequently by means of a line of buoys marking the deep-water channel. This gave an area of 18,857 square metres. Hence the thickness of the film of oil was 53 millionths of a mm. It is, of course, possible that the oil had spread still further and had only ceased to influence the ripples on the surface. In that case the film must have been even thinner. THE applications of electricity to every-day life seem to be almost infinite; the latest development being an electrical horsewhip described in Électricité. This is said to be de signed for the use of a "sportsman," and consists of a celluloid handle containing a small induction coil, together with a battery, the circuit being closed by means of a spring push. Two wires carry the current to the extremity of the whip, which is furnished with two small copper plates having points fixed to them of sufficient length to penetrate the coat of the horse, and yet not being sharp enough to inflict a wound. In a note contributed to the Accademia dei Lincei, Augusto Righi gives a short description of a form of apparatus he has used for producing Hertzian oscillations of short wave-length and exhibiting their properties to an audience. The oscillator consists of two rods furnished with balls at either end and placed between the discharger of a Holtz machine, leaving a gap of about 4 centimetres at each end, and one of about 3 mm. at the middle. The two rods pass through the sides of a glass vessel containing oil, so that the middle pair of knobs are surrounded by oil. The resonator consists of a nearly complete circle of wire, the gap being filled by a Geissler tube. With the above apparatus the author has carried on a series of experiments on the reflection, refraction, and interference of these electrical waves. AN abstract of a paper by C. H. Morse appears in the Electrician, giving an account of the damage to the water-pipes in Cambridge (Mass.), caused by the electrolytic action of the return current from the electric cars. Pipes composed of lead, iron, galvanised iron, brass, and rustless iron were in turn tried and found to deteriorate quickly. Such an amount of current was found to be flowing along the pipes that, upon attempting to make a joint by putting oakum round the pipe, an electric arc was formed and set the oakum on fire. The damage has to a great extent been checked by connecting the gas and waterpipes together, and also to the negative pole of the dynamos which supply the power to the railway. At the beginning of this year (says the Revue Scientifique, June 17, there were 1168 submarine cables in existence, of which 880 belonged to different dominions and 288 to private companies. The former possessed a length of 16,652 miles, and the latter had a length of 144,743 miles, thus the total length was 161,395 miles. Fifty-four of these cables belong to the state in France, the length being 3979 miles; and Germany owns 46 cables, having a total length of 2025 miles. There are 14 Anglo-French cables, 10 Anglo-Belgian, 8 Anglo-Dutch, and 13 AngloGerman. Of the cables possessed by private companies the Eastern Extension, Australasia, and China Telegraph Co. head the list with 25 cables and a mileage of 18,205; the Great Northern Telegraph Co. follow with 24 cables, having a tota length of 6948 miles; then come the West India and Panama Telegraph Co. with 22 cables extending through 5240 miles: and the Western and Brazilian Telegraph Co. with 15 cables stretching over 5408 miles. The French Society of Submarine Telegraphs possess 14 cables having a total length of 3754 miles. THE "shell-beds," or shelly clays, in the north of Scotland— at Clavia near Inverness, and on the east coast of Aberdeenshire, have been investigated by Mr. Dugald Bell, and the results of his researches were communicated to the Glasgow Geological Society on May 25, under the title "The alleged proofs of submergence in Britain, during the Glacial Epoch." Mr. Bell holds that it is doubtful if this clay were really in place, as part of an ancient sea-bottom, during the glacial epoch. He thinks also that the "red clay" of East Aberdeenshire, described by Mr. Jamieson, cannot be accepted as a satis factory proof of submergence, indeed, in some respects, its characteristics seem to be inconsistent with that theory. FROM the Pioneer Mail we learn that Mrs. J. S. Mackay has a superb snow leopard at Kulu, in the Punjab. Though the animal is nearly full-grown, he is practically free and lies about the house all day like a huge cat, or romps with his mistress. His ultimate destination is the Zoological Gardens of London. Should he be brought over alive he will be the only animal of his kind in Europe. IN a paper, "Sulla presenza di batteri patogeni nella saliva di alcuni animali domestici " (Fiocca: Annali dell' Istituto d'Igiene Sperimentale della R. Università di Roma), an examination of the saliva of numerous horses, dogs, and cats is recorded. The saliva of the horse was found to contain diverse bacilli, also streptococci, staphylococci, and one spirillum. Amongst these organisms three were discovered which possessed pathogenic properties; and one of these, a bacillus, was very frequently found, for out of fifteen different samples of saliva inoculated into guinea-pigs it was only once absent. This organism is distributed in soil, and it is very possibly also frequently present on grass and hay, and hence its prevalence in the saliva of horses. The saliva of the cat presented a very different appear. ance from that of the horse, being very rich in cocci and minute bacilli. A new bacillus (Bacillus salivarius felis), extremely characteristic of cats' saliva, was isolated and found to be specially pathogenic to rabbits and guinea-pigs, these animals dying from its effects in twenty-four hours. The dog's saliva was found to contain the largest variety of bacteria, amongst the pathogenic forms isolated being the B. pseudo-ædematis maligni, and the Staphylococcus pyogenes aureus. SOME investigations on the antagonistic effect produced by the Bacillus fluorescens liquefaciens on other organisms have been made by Olitzky (Ueber die antagonistischen Wirkungen des B. fluorescens liquefaciens und seine hygienische Bedeutung, Bern, 1891). Cultures of this bacillus were either streaked on to nutritive agar-agar side by side with other or ganisms, or the latter were separately inoculated on to culture material in which this bacillus had grown, but which before being used for the second time was re-sterilised, the growth being thus destroyed, but the products remaining. It was found that the tubercle bacillus and the pneumococcus of Fraenkel were quite unaffected, whilst the B. prodigiosus only refused to grow in the re-sterilised culture material. On the other hand the Staphylococcus pyogenes aureus, the anthrax bacillus, and the typhoid bacillus were greatly impeded in their development, and no growths whatever made their appearance in the resterilised culture material. The cholera bacillus and the B. pyocyaneus were also affected, but to a smaller extent. SHORTLY before his death, Mr. Darwin informed Sir J. D. Hooker, F.R.S., that "the difficulties he had experienced in accurately designating the many plants which he had studied, and ascertaining their native countries, had suggested to him the compilation of an Index to the Names and Authorities of all Known Flowering Plants and their Countries' as a work of supreme importance to students of systematic and geographical botany, and to horticulturists." "At his request," adds Sir J. D. Hooker, "I undertook to direct and supervise such a work." The Clarendon Press announces that Part I. of this "Index Kewensis" is now ready, that Part II. is well advanced, and that the completion of the whole work may be expected next year. THE first part of Prof. A. Newton's "Dictionary of Birds" has just been published by Messrs. A. and C. Black. It extends from aasvogel to the gare fowl, or great auk, and runs into 304 pages. The work is founded upon a series of articles contributed by Prof. Newton to the ninth edition of the "Encyclopædia Britannica." Important additions have been furnished by Dr. Hans Gadow, and for other contributions Mr. R. Lydekker, Prof. C. S. Roy (who has written an interesting article on "Flight"), and Dr. R. W. Shufeldt are responsible. A commendable feature is the inclusion of many names of birds, such as the caracara, koel, and mollymawk, which are frequently found in books of travel but are not explained in an ordinary dictionary. Compound names of the crow-shrike and thrushtitmouse kind have, however, been omitted. The MR. R. L. JACK, the Government Geologist of Queensland, has prepared a report on the Russell River Gold Field. report is accompanied by a geological map of the district. We have received a dissertation by Mr. E. M. Blake, in which he discusses the application of the method of indeterminate coefficients and exponents to the formal determination of those integrals, of certain systems of differential equations, which are expressible as series. THE Harvard University Bulletin for May is a long list of accessions to the University Library. This list includes, in addition to recently-published books and pamphlets, a number of extensive and important works of earlier date. Nearly one hundred and fifty books in the list are concerned with science and the arts. MESSRS. MACMILLAN AND Co. have published a second edition of "Lessons in Elementary Biology," by Prof. T. Jeffery Parker. The whole of the book has been thoroughly revised, and two of the lessons have been largely rewritten. A number of new figures have also been added. MR. W. H. HUDSON, the author of "Idle Days in Patagonia," recently reviewed in these columns, has completed a book called "Birds in a Village," which will be published in a few days by Messrs. Chapman and Hall. The book does not profess to be a serious contribution to ornithology, but is intended rather for the general reader. Among other chapters of interest is one on the introduction of exotic birds, and another on bird-life in London. In the concluding portions of the book the subject of bird-protection is dealt with at considerable length. A REFERENCE list of the land and freshwater mollusca of New Zealand has been prepared by Messrs. C. Hedley and H. Suter, and appears in the "Proceedings of the Linnean Society of New South Wales," vol. vii., December, 1892. The authors are of the opinion that as the New Zealand fauna becomes better known, its insular character stands out more prominently. Foreign genera, which have been imposed on the fauna, have been eliminated one by one, and many genera which might have been expected to occur, since they are prevalent in neighbouring countries, have not yet been detected. Crosse remarked that "The terrestrial and fluviatile molluscan fauna of New Zealand approximates more to that of New Caledonia, in spite of the considerable distance that separates the two countries, than to that of Australia" (Jour. de Conch. xxviii. p. 37), and the authors think his idea has hardly received the attention which it merits. THE "Tourist Guide to the Continent," published for the Great Eastern Railway Company, has reached its fourteenth year of issue. It is edited by Mr. Percy Lindley, and includes descriptions of things and places of interest in Holland, Germany, Belgium, and Switzerland. AFTER Mr. Francis Galton, F.R.S., had completed his work on "Finger Prints" he came into possession of the impres sions of the fore and middle fingers of the right hand of eight different persons at Hooghly, Bengal, made in the first instance in 1878, and secondly in 1892. These prints have afforded the text for a discussion as to the persistence of patterns, and the result of the decipherment is now published as a supplementary chapter to the above-named book. Though the prints were not obtained by the best means, a comparison of the reproductions of them shows clearly that the "sign-manual" furnishes unquestionable evidence as to a person's identity, and further, the testimony is of such a character that any juryman would be able to appreciate its weight. WE have received a communication from "Waterdale," in which he calls attention to the fact that he subsequently corrected many of the errors pointed out in the review of his researches which appeared in vol. xlvii. p. 601. A CORRESPONDENT desires to know where to find any cele brated and artistic hedgerows of elms within about thirty or forty miles of London. Perhaps one of our readers will furnish the required information. MESSRS. FUNK AND WAGNALL, New York, have just issued a complete prospectus of "A Standard Dictionary of the English Language," a work that has been in preparation for several years, and is now nearly completed. The dictionary will contain 280,000 words in about 2200 pages of medium quarto, and will be embellished with more than 4000 illustrations specially prepared for it. One of the many distinguishing features is the comprehensive provision that has been made for definitions by specialists in various arts and sciences. Handicraft terms have been gathered with great completeness and grouped under the different trades, and by applying a similar system of grouping to the names of fruits, flowers, weights, measures, stars, &c., the facts concerning this class of words are given in a very complete manner. For example, under constellation are given the names of all the constellations, and under apple are found the names of nearly four hundred varieties. Judging from the specimen pages, and the list of men eminent in science and literature who are concerned in the compilation, the dictionary will be the handiest, simplest, and most trustworthy publication of its kind. THE Johns Hopkins University Circular, No. 106, is chiefly taken up with morphological notes from the biological laboratory of the Johns Hopkins University. Prof. William K. Brooks contributes two important notes on the Salpa embryo, and Mr. M. M. Metcalf describes an apparently new species of Octacnemus, a deep-sea, Salpa-like tunicate. A memoir on the genus Salpa,. by Prof. Brooks, will shortly be published. It will contain about three hundred and fifty quarto pages, with sixty coloured plates. The memoir is based for the most part upon material collected by the United States Fish Commission. "ELECTRIC Light Installations and the Management of Accumulators," by Sir David Salomons, Bart., has reached a seventh edition. This edition has been, to a large extent, rewritten, and is now published by Messrs. Whittaker and Co. under the title "The Management of Accumulators," as the first volume of a series dealing with electric light installations. Two further papers upon azoimide, NH, are contributed to the current number of the Berichte by Prof. Curtius. In the first, a brief but important communication, it is shown that NH2, azoimide may be prepared directly from hydrazine, by the NH2 It is only necessary to lead the red oxides of nitrogen evolved from a mixture of nitric acid and arsenious oxide into an ice-cold aqueous solution of hydrazine hydrate until a vigorous evolution of gas, due to decomposition, commences. A dilute aqueous solution of azoimide is thus obtained with which most of the reactions of the substance can be 'performed. It is preferable, however, to first condense the red gaseous mixture by means of ice and salt, and to pour the blue liquid, a few drops at a time, into the cold hydrazine solution until the evolution of gas begins. The experiment is unattended by any danger, and is therefore admirably adapted for lecture purposes. Now that hydrazine is so well known and so readily obtained, the sulphate being already a commercial article, this mode of obtaining azoimide will doubtless be adopted by most lecturers for class demonstration, especially as the reaction is one of such fundamental theoretical importance. and distilled, when azomide passes over along with the steam. The ethereal extract contains the aniline together with diazobenzene imide produced according to the second mode of decomposition. In the second communication Prof. Curtius describes an ininteresting new organic synthesis of azoimide. When hydrazine hydrate is caused to act upon a salt of diazobenzene, a fugitive compound is obtained of the constitution indicated by the formula C.HN: N.NH.NH,. This compound might be expected to decompose in two ways, breaking up either at the double linkage or at the single linkage between the NH and NH groups. According to the former mode there would be a migration of two hydrogen atoms from two different nitrogen atoms to a third nitrogen atom with production of aniline and azoimide, CHAN: N.NH. NH, C6H5NH2 + N2H. According to the latter mode of decomposition one hydrogen atom would migrate and form ammonia with the last amido group, leaving diazobenzene imide, thus: CHAN: N.NH.NH, CH2N NH2. As a matter of fact both decompositions occur, the latter somewhat predominating. NOTES from the Marine Biological Station, Plymouth.—The arrival of Midsummer renders desirable a summary of the records which have been made in this paragraph during the past six months of the breeding seasons of marine animals at Plymouth. The records have approximately indicated the commencement of the breeding seasons; but it should be premised that in the great majority of instances the period of reproduction is prolonged throughout the summer months, and is already at an end only in a few isolated cases. The following have been recorded:-The Gymnoblastic Hydroids Tubularia bellis, Clava multicornis and cornea, Eudendrium ramosum and capillare, together with the Anthomedusæ Rathkea octopunctata (now over), Bougainvillea ramosa, Amphinema Titania, Sarsia prolifera and tubulosa, Podocoryne carnea and Corymorpha nutans; the Calyptoblastic Hydroids Halecium (halecinum and Beanii), Plumularia setacea and pinnata, Antennularia ramosa and antennina, Sertularella (Gayi), Sertularia argentea and pumila, Hydrallmania (falcata), Gonothyraa Lovéni, together with the Leptomedusæ Obelia lucifera, Clytia Johnstoni, Irene pellucida, Phialidium variabile, Laodice cruciata, Thaumantias octona, Forbesii, and Thompsoni; the Ctenophore Hormiphora plumosa; the Actinians Cercanthus (Arachnactis,— -now over), Halcampa chrysanthellum, Cereus pedunculatus, Bunodes verrucosa, Urticina felina and Actinia equina; the Nemertines Cephalothrix linearis and bioculata, Amphiporus dissimulans, Riches (= pulcher of previous record, March 30), Nemertes Neesii, and Lineus obscurus; the Polychaeta Phyllodoce maculata, Cirratulus cirratus, Polydora (flava ?), Sabellaria spinulosa, and various Terebellide and Serpulida. The Polynoïd larvæ which swarmed in the Sound in the early Spring are no longer to be obtained. The Mollusca, Crustacea, Echinodermata and Chordata will be summarised next week. It is quite easy, however, to isolate 10 per cent. of the theoretical yield of azoimide. Equi-molecular saturated aqueous solutions of hydrazine sulphate and diazobenzene sulphate are mixed and poured into a 3 per cent. solution of sodium hydrate. A turbidity is at once produced, which eventually coalesces into an oil. This is extracted with ether and ammonia, expelled from the aqueous solution by boiling. The liquid, which contains the sodium salt of azoimide, is then rendered slightly acid with sulphuric acid THE additions to the Zoological Society's Gardens during the past week include three Peba Armadillos (Tatusia peba, 8 8 9 ) from South America, presented by Mr. Woodbine Parish; two Brazilian Cariamas (Cariama cristata) from Paraguay, presented by Mr. A. E. Macalister Hadwen; five Spotted-billed Ducks (Anas pacilorhyncha, 4 8 1 9 ) from India, presented by Sir E. C. Buck, C.M.Z. S.; a Guillemot (Lomvia troile) British, presented by Mr. T. A. Cotton, F.Z.S.; two Chiff-chaffs (Phylloscopus rufus), two Yellow Wagtails (Motacilla flava) British, presented by Miss McGill; a Naked-necked Iguana (Iguana delicatissima) from the Caicas Islands, West Indies, presented by Lady Blake; a Lobed Chameleon (Chamæleon parvilobus) from Barberton, Transvaal, presented by Dr. Percy Rendall; two Capybaras (Hydrocharus capybara) from South America, purchased; an English Wild Bull (Bos taurus, var.), a Burrhel Wild Sheep (Ovis burrhel, ?), a Derbian Wallaby (Halmaturus derbianus, ?) born in the Gardens. OUR ASTRONOMICAL COLUMN. A NEW VARIABLE u CYGNUS.-In photographing the region of a Cygni, Dr. Max Wolf (Astronomischen Nachrichten, No. 3168), on examining the plates, has found a new variable, its position for 1893 0 being R. A. 20h. 47 2m., Decl. +45° 49'. The star, he says, is very easy to find, lying as it does in the south right-angle corner of a right-angled triangle, the stars in the other corners being B. D. stars +45 3300 and +45°*3302. The brightness, as obtained from the plates, gave the following numbers: |
