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is received on the one half of a small piece of ground-glass, the other half of which may be evenly illuminated by the light from a standard osmium lamp. By varying the distance of the latter the illumination of both halves may be equalised, and the distance of the lamp read off on a suitably divided scale.

M. Deslandres suggests that this photometer will be found extremely useful in determining the most suitable localities for solar observations of all kinds. By the interposition of violet glass the relative intensity of the glare which would affect spectroheliograph observations might be determined, and, similarly, the substitution of red glass would show the suitability of the atmosphere for the experiments on the photography of the corona, in which it is proposed to utilise the red rays (Comptes rendus, No. 3, 1906).

A NOVEL PLANISPHERE.-In collaboration with Mr. G. P. Serviss, of the Brooklyn Institute, Mr. L. Barritt, of 150 Nassau Street, New York, has recently published a planisphere which should prove very useful to amateur astronomers, teachers, and others who are interested in celestial phenomena.

As regards the constellations the apparatus is similar to other planispheres, but, in addition, it allows the user to determine the approximate positions of the planets, the sun, and the moon at any time and date. This is effected by having the ecliptic divided up into degrees, so that small discs representing the various bodies may be affixed at any indicated point in their respective paths. A set of tables accompanying the apparatus shows where each disc is to be affixed at different dates during the next twenty years, and thus by placing these discs as directed, and rotating the circular card for the current time and date in the usual way, the actual position of each celestial body may be seen at a glance. The observer may also, of course, determine approximately the times of rising and setting for each body on any date during the period 19061925. The price of the complete apparatus is five dollars.

THE OXFORD UNIVERSITY OBSERVATORY.-Prof. Turner's report of the work done at the Oxford University Observatory during the period May 1, 1905, to April 30, 1906, directs attention to the fact that the observatory staff is almost entirely engaged

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four times during previous ceremonies; these "thundermen" select the dancers, and it is a considerable honour to be thus chosen, for each dancer is held to bear a part of the sufferings of the tribe. Camp is moved on the day before the dance, the time of the ceremony having been previously proclaimed; continence must be observed by all who take part.

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Five days in all were needed when Mr. Dorsey was present, of which the first was taken up with preparations. The forenoon of the second day was occupied with a mimic combat, after which the ceremonial huts were removed into position by female relatives of the priests. The supposed enemies in the fight were the men who left the camp to spy the centre-pole " of the dance lodge; while the lodge was being erected, the centre-pole was felled and brought to the camp; at the same time four altars were prepared, one for each hut. The third day opened with a race to the centre-pole, which was still outside the camp, lying crosswise to the sun. It was then painted and raised into position; an altar was prepared, and before it was finished the dancers entered the lodge, bringing a painted buffalo skull. Prayers were offered by the dancers, and the dance began; it was continued at intervals during the whole of that day and night, and on both the fourth and fifth days the sunrise performance was specially important; on several occasions the priests made before the performers what seem to be hypnotic passes. Until the final dance all fasted; female relatives then brought food to the dancers, and the chief laved the mouth and

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Rai sing the Centre Pole on the third day of the Ponca Sun Dance.

upon the proof-reading of the Oxford section of the Astrographic Catalogue, and that, in consequence, it does not seem advisable to undertake any new piece of observational work. The first of the eight volumes of the catalogue is now practically ready, and the printing of it has been commenced. It contains the measures of 66,000 starimages on the 160 plates with centres of declination +31°.

The report also contains brief accounts of the eclipse expedition to Aswan, and of the meeting of the Solar Research Union at Oxford in September, 1905.

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sprinkled the head of each dancer with water. The last ceremony was the offering of a portion of skin, cut from the shoulder of each dancer, to the sun, by placing it at the foot of the centre-pole.

All the participants were painted more than once, and careful descriptions of them are given, together with coloured plates of the more important. The remainder of the thirty-five plates show the altars and various scenes of the rites.

Mr. Dorsey was struck by the comparative simplicity of the ceremony, but he suggests that it may possibly be a case of degeneration. The centre-pole represents an enemy, and in its fork is supposed to be the Thunder Bird's nest ; the altar is the sun or fireplace, which existed in the beginning; the buffalo bull came from the interior of the earth. The altar consists of the sage plant, symbolical of the people, the sun, and the buffalo. No satisfactory account of the origin of the dance could be obtained, and Mr. Dorsey offers no suggestion as to its significance. It has, however, been dealt with in the annual reports of the Bureau of Ethnology (vol. xi.) as regards the Dakota, and vol. iv. of the Field Columbian series contains a long account of the Arapaho dance by Mr. Dorsey himself. The statement on p. 88 of the present report that torture is not found among the Arapaho appears to be directly contradicted by the latter report (pp. 179 et seq). N. W. T.

GEOLOGICAL STUDIES IN SOUTH AFRICA. THE Report of the Geological Survey of the Transvaal

Mines Department for 1904 (Pretoria, 1905, price 7s. 6d.) is a folio volume, issued at a very moderate price. It contains twenty-three plates, from which our figures are reductions, and two large coloured maps, the latter being conveniently placed in an envelope

the glacial Dwyka conglomerate were traversed (Fig. 2). The boulder-bed, as described in supplementary notes by Mr. Mellor, does not seem more than 50 feet thick, and is associated with sandstones. It was laid down, as in other cases, on a land-surface eroded by streams, and the original topography is now being revealed by the denuding action of the Elands River and other agents.

Mr. A. L. Hall (p. 37) describes the geology of the tin fields north-east of Pretoria, where the ore occurs promisingly in a rock of greisen type; and Mr. Mellor (p. 45) deals with the picturesque area of Rhenoster Kop. The Permian glacial striation in this district, seen on the uptilted Waterberg Sandstones, has an almost constant direction of S. 33° E. After other papers on special districts, Mr. S. M. Tweddill describes some of the rocks collected, and has been allowed a handsome series of photographic plates, showing his thin slices in ordinary light and with crossed nicols. The latter figures are produced by the three-colour process, but it is questionable if much is gained by them. Colour-photographs of the sections in ordinary light would probably be more effective, and would equally serve to confirm the author's determinations. The " acicular crystals of Clay-slate " in the description of Plate XV.a puzzle us not a little, especially as in the text on p. 76 the "stellate forms" are similarly said "to be clay-slate." In a country where everything depends on fieldrelations, where the scale of phenomena is large, where the mention new discovery suggests comparison with something else a thousand miles away, one probably expects too much from the petrographer. One can imagine the prospector, who has returned bronzed and muscular after his days upon the veld, reading the bare descriptions

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FIG. 1.-Weathering of granite on characteristic kopje near Chuniespoort, N. Transvaal.

at the end. The cessation of topographical work in the country must in future hamper systematic geological mapping, and the Geological Society of South Africa has already approached the Colonial Secretary in Pretoria on the subject (Proc. Geol. Soc., S. Africa, 1906, p. liv). It might be thought that military considerations alone would be sufficient to place an accurate map among the first requirements of the colony.

The director of the Survey, Mr. Kynaston, describes a traverse of the country between Pretoria and Pietersburg, during which he visited the remarkable Salt Pan, some twenty-five miles N.N.W. of Pretoria. This lake, which is about as salt as the Dead Sea, lies in a circle of granite hills, 250 feet below their crest, and about 200 feet below the general level of the country on their outer side. Its salts include 72.70 per cent. of sodium chloride and 27.25 per cent. of sodium carbonate. Except that an explosive origin has been suggested by Cohen, no adequate explanation of the hollow is as yet forthcoming. Considering, moreover, the antiquity of the last volcanic eruptions in this area, a crater of explosion ought to have become long ago filled up by products of denudation. One

of a

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FIG. 2.-Weathering of Permian glacial conglomerate, showing the original boulders, Toitskraal,

feels tempted to ask if it is possible for the materials filling an igneous neck to sink back long after they have solidified. Could the fragmental materials so common in South African pipes behave in this way? Mr. A. W. Rogers has cited cases where the weathering of these necks has caused hollows at the surface; but the Salt Pan near Pretoria is 200 feet to 250 feet in depth.

On Mr. Kynaston's return journey from the mouth of the Elands River, the most northerly known outliers of

Elands River.

of rocks with a certain irritation. If they could be inserted in connection with the account of the masses in the field, their true interest would at once appear, for the South African of all men has a pleasurable keenness for geology. This fact is well attested by the publication of the dis

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cussions that take place at the meetings of the Geological Society of South Africa (Proceedings of the Society for 1905), and by the considerable space given to written criticisms and replies. The Transactions would be very incomplete without these additions, which may be commended to the notice of many publishing societies in our islands. Dr. F. W. Voit, for instance, read a paper (Trans. Geol. Soc., S. Africa, vol. viii., p. 106) on September 4, 1905, entitled "Preliminary Notes on Fundamental Gneiss Formation' in South Africa,' in which he claimed that the gneisses of the Limpopo Flats correspond to the fundamental formation of the continent of Europe. At the meeting three members contributed structural and mineralogical details from their own notebooks (Proc. for 1905, p. lvii), recorded with an altogether admirable clearness of expression. The full paper was read on October 30, 1905 (Trans., p. 141). Dr. Voit points out, in agreement with his predecessors, that the main granite is intrusive in the Swaziland beds, "long drawn out lenses of quartzite, chlorite, actinolite, and other schists, swimming, as it were, in a granite magma." But the Limpopo gneisses are, for him, still older, and he looks forward to finding the granite intrusive in them also. By the way, we must object to his using, on p. 145, the term "interbedded igneous sheets" for intrusive masses that have come up along planes of fracture in the granitoid mass. On November 20 (Proc. for 1905, p. lxv) the author sent in a letter in which he supported his views by quoting Mr. Anderson's observations in Natal, and on December 18 Messrs. Sandberg and Jorissen made a reply to Dr. Voit, in which Credner is cited as their authority, in a manner that almost recalls the Wernerian discussions of a hundred years ago. The bottom, if we may speak irreverently, is here knocked out of the " Urgneissformation" with considerable vigour, and the references to European literature, though disfigured by a few misprinted place-names, add zest to a spirited discussion.

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Mr.

Mr. J. P. Johnson (Trans. Geol. Soc., S. Africa, vol. viii., p. 135) describes and illustrates primitive stone implements from the plateau of the Victoria Falls. Lamplugh directed attention to these (Report of Brit. Association for 1905, p. 300) as being possibly older than the excavation of the Batoka Gorge, and Colonel Feilden has already urged their importance upon the readers of this Journal (NATURE, vol. Ixxiii., p. 77). We trust that we have said enough to show that geology in the best sense, as a critical and comparative science, flourishes in the dusty and inchoate city of Johannesburg. Probably there is no part of the world where geological phenomena play so large a part in the thoughts of cultivated men. GRENVILLE A. J. COLE.

evening the committee of the exhibition entertained the members of the conference at dinner.

On October 2 the members went to Pavia, where M. Gamba showed them over the observatory, and liberated two ballons-sondes. After visiting the university the members were entertained at luncheon by the municipality of the town.

The second meeting was held on October 3 under the presidency of Prof. Assmann and M. Teisserenc de Bort. Dr. Erk urged the necessity of making ascents in the neighbourhood of the Alps for studying local phenomena, such as the Föhn. M. de Quervain explained a method of using small pilot balloons for determining the winds at different altitudes; small india-rubber balloons were liberated and watched with a theodolite; assuming that the balloon ascended with uniform velocity, it was possible to determine its course from one station. Prof. Hergesell spoke very highly of the method which he had used at Strasburg and elsewhere, and mentioned that in Spitsbergen he had watched the balloon to a distance of 80 kilometres. M. Ebert explained his method of determining the deformation of the electrical equipotential surfaces in the neighbourhood of a balloon, and exhibited apparatus for measuring the ionisation of the air.

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The third meeting was held in the afternoon of October 3 under the presidency of Colonel Vives y Vich and Mr. Cave. General Rykatchew and M. Riabouschinsky read the reports of the work of their observatories. M. de Quervain read a paper on the thermal inertia of thermometers used in kite and balloon ascents. In connection with this an important discussion took place on the relative value of ballons-sondes and kites for the study of the air up to 5000 metres or so. Prof. Hergesell strongly advocated the use of balloons in preference to kites; General Rykatchew and M. Berson thought that kites were far more suitable.

Mr. Rotch read a paper on the ascents of ballons-sondes in America, and General Rykatchew read a paper on the temperature gradient as observed at Pavlovsk.

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Prof. Hergesell explained a method of recording vertical movements in the atmosphere by attaching a log to balloons. M. de Quervain gave proofs of the reality of the isothermic zone.

In the morning of October 4 the members visited the aëronautical section of the exhibition, and ballons-sondes were liberated by M. Gamba, M. Teisserenc de Bort, and Prof. Hergesell. In the afternoon the fourth meeting was held under the presidency of Mr. Rotch and M. Scheimpflug. General Rykatchew described M. Kouznetzow's method of determining the height of clouds at night by means of a search-light, and gave some of the results obtained at Pavlovsk. M. Köppen, M. Teisserenc de Bort, and Mr. Rotch observed that the method had been used at Hamburg, in France, and in America. Mr. Alexander read a communication on the forms of propellers for flying machines.

M. Moedebeck urged the necessity of having descriptive charts for aëronautical purposes that would show, for example, dangerous places such as those where there were wires carrying currents at a high potential. M. Scheimpflug gave an account of his method of making maps from photographs taken from balloons. M. Teisserenc de Bort read a report on the necessity of extending the number of stations at which ascents are made, and Prof. Hergesell said he would make every effort to carry out this suggestion. Prof. Palazzo said he hoped that he would shortly be able to establish a kite station on Mount Etna. M. Hinterstoisser then gave a lecture on aëronautics from the points of view of science and sport, and illustrated it with lantern-slides.

On Friday, October 5. M. Mangili, president of the committee of the exhibition, entertained the members in an excursion by steamboat on the Lago Maggiore. It had been proposed to make kite ascents, but this proved impossible owing to want of wind. Prof. Hergesell attempted to demonstrate his method of dropping ballonssondes at sea. Unfortunately his apparatus had not arrived, and the ballon-sonde sent up did not come down as soon as was intended, and was last seen at a great height

AERONAUTICS AND METEOROLOGY. THE fifth conference of the International Commission

of Scientific Aeronautics was held at Milan, and commenced its sittings on October 1. The conference was formally opened by Prof. Celoria, representing the committee of the Milan Exhibition, M. Gavazzi, representing the municipality, Prof. Palazzo, and Prof. Hergesell, president of the commission.

A large number of representatives attended the conference; Mr. Dines represented the Meteorological Office, and the other English members were Major Baden-Powell, Mr. Patrick Alexander, and Mr. Charles Cave.

The first meeting for the discussion of scientific questions was held in the afternoon of October 1 under the presidency of General Rykatchew and Prof. Palazzo. Prof. Hergesell read his report, and various questions were discussed relating to the business of the conference. In the, and still ascending.

The fifth meeting was held on October 6 under the presidency of M. Köppen and Mr. Dines. Prof. Hergesell explained his method of making balloon ascents at sea. Two balloons are used, one being held by a fastening that can be opened electrically; a small battery is sent up with the instruments, and the electromagnetic release can be worked by a contact actuated by the barometer, or by a contact on the recording drum of the instruments; the latter has been found the. better method in practice. One balloon being released, the system slowly falls, until a float hanging below the instruments touches the water; the balloon is inflated so as to hold the instruments above the sea, the float alone touching the water. Both M. Teisserenc de Bort and Prof. Hergesell stated that they are designing a method by which instruments may be dropped from ballons-sondes by wireless telegraphy; the former also hopes to be able to detach kites by the same method. M. Teisserenc de Bort thought that for work on land, when for any reason the height of the ascent had to be limited, his method of using paper balloons was to be preferred.

Baron von Bassus exhibited an instrument for reading the records of kite and balloon ascents. He claimed that his instrument would give readings with great accuracy, and that simultaneous points on the different curves could be obtained easily. He thought that by its use small inversions of temperature could be detected that were often overlooked.

M. Teisserenc de Bort then gave an account of the expedition to the equatorial regions of the Atlantic organised by Mr. Rotch and himself. Extremely good results had been obtained, and, contrary to expectation, it was found that in the upper air far lower temperatures were recorded over the equator than at corresponding heights in temperate latitudes. Over the equator the isothermal zone did not seem to exist, but the temperature went on decreasing up to the highest points reached. At heights of 13 to 14 kilometres temperatures had been found as low as -80° C.

At the concluding meeting, held on the afternoon of October 6, various resolutions were passed relating to future conferences. It was resolved that in future the meetings should be held every three years, and that, so far as possible, they should be restricted to three days. Papers relating to instruments and to methods of observation should have precedence over those dealing with the results of observations. It was also agreed that, instead of the present arrangement of having one international day each month, there should be three days together four times a year for the purpose of the international ascents. This arrangement should come into force in March, 1907.

The president then read telegrams that it was proposed to send to the King and Queen of Italy, to the Spanish Minister of War and others, who had taken an interest in the work of the commission. After several speeches the conference then closed.

On Sunday, October 7. an aëronautic fête was held in the grounds of the exhibition, and eight balloons made ascents, several members of the conference being passengers. The majority of the balloons descended in the neighbourhood of Pavia.

MODERN NEEDS IN UNIVERSITIES1

UNIVERSITIES in America and Canada are paying

more and more attention to our own language and classics, and less and less to Latin and Greek. Not that the latter are excluded, but they no longer outrank other branches of study. Their doors are open to the new forces of the day, and they have at their heads a body of remarkably able and zealous men who not only keep the universities foremost as progressive educative agencies, but whose potent voices are heard upon public questions, as leaders of the higher ideals in politics and national affairs. Much can also be said of those occupying similar positions in Scotland. St. Andrews has just erected a new chemical laboratory for research, Dundee is about to erect such 1 From an address delivered by Dr. Andrew Carnegie at the opening of new buildings for the natural philoscphy and engineering departments of the University of Edinburgh on October 16.

schools as we are to-day to open for Edinburgh. We all know where Glasgow stands in modern branches of education. Aberdeen has just been supplied with new buildings efficiently equipped for the study of science and medicine. No less than eleven new chambers have been assigned to modern studies, to meet pressing demands. The University of London recently separated economics and engineering from arts, and established separate faculties. It is also announced that owing to the unrivalled facilities found in the metropolis, it has to be prepared for the advent of new schools of practical study or research. In the new Universities of Liverpool, Manchester, Birmingham, Leeds, and Sheffield, modern studies are to be paramount. They are to resemble the American type. Harvard University has just been left 800,000l. sterling for an institute of technology, but as one of the foremost of such schools is in Boston, she has proposed union with that, and offered if needed new buildings, as part of the University. McGill University, Montreal, has just had handed over to her the agricultural college built by Sir Wm. Macdonald at a cost of 600,000l. Thus the millions are now being devoted to science and practical studies, theology and classics being in the opinion of donors already amply provided for. This betokens a steady march forward from the policy of the past, not that it is desirable to exclude any of the former university courses, but there should be added others needed to guide and advance the new knowledge which is creating new conditions.

But

I judge Scotland to be as far and as happily advanced beyond England in university as she is in elementary public-school education. Her universities are not for a class, but for the people, stirring hives of Democracy. Scotland may expect the new universities of the five principal English cities to approach nearer to American institutions in character, for their educational atmosphere and aims are very different indeed from those of Oxford and Cambridge, and similar to those of the great American cities. They will be modern universities, fully equipp for the work of to-day. Scotland has to keep marching on. The progress of scientific departments in British unversities, considerable as it has recently been, of which the schools we are about to open here to-day are gratifxing evidence, yet has not kept pace with the startling progress of science itself and the wonderful discoveries which threaten to revolutionise human conceptions. The discovery of argon by Rayleigh, Becquerel's rays, Rontgen rays, uranium, and, finally, the Curies' radium, threatens to relegate the old atomic theory itself to the list of dis. carded "creeds outworn,' except that science has no creeds. She has only theories and opinions based upon phenomena, all held lightly because subject to progressive discoveries that may be revealed through her unceasing search for knowledge. Science has no preconceived dogmas; she has but one end, the pursuit of truth. I was long claimed for the classics that they alone appeals to the imagination, while dry, prosaic science was incapable of doing so. This is a grievous mistake. The recent discoveries that have startled the world are sublime, and appeal with intense force to the imaginative faculties of man. The scientific man of to-day lives in an atmosphere of wonder, arousing all his higher powers and compelling reverence. At each startling revelation he feels "as some watcher of the skies when a new comet swims into his ken."

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The older branches of learning in our universities ma well welcome the newer branch, cap in hand, not only * the foundation of material progress, but also as one -Í the very highest agencies in the imaginative domain. It is the man of science in our day

"Who can extract each particular virtue from the sun,
And teach dull nature what her forces are."

This mighty force of our day-science-has hitherto b--the Cinderella of the sisterhood of knowledge, but th Prince has appeared at last and taken her by the hand It is now the turn of the elder sisters to greet the orcs neglected princess. She will more than justify the mill which are now being showered upon her in the most progressive lands. Thus has the university developed to the present all-embracing type through the successive reiges of scholasticism, theology and ancient classics, alwar

behind the age, conservative in the highest degree. Science has arisen and established her claim to equality. We have long had the Republic of Letters; we now hail the Republic of Knowledge. The ceremony of to-day bears testimony to the growing power of Edinburgh University; her prominence as a teacher of one of the noblest of all professions, perhaps the one in which those who practise it devote gratuitously a greater part of their time and attention than the members of any other profession, is not likely to be lost. On the contrary, all evidence to-day leads to the opposite conclusion. She is to remain famous for her medical school, and is now also destined to increase her reputation as a scientific instructor through the possession of the increased facilities now provided. The physical laboratory and engineering school, which, with the cordial cooperation of the municipal authorities, have been so ably secured by the principal and the University Court, are the necessary tools which will enable her to extend her work in these important branches of knowledge. They mark an epoch in her long career, and are to testify to future generations that the officials in charge of her work in the beginning of the twentieth century were alive to the duty of keeping her abreast of the new knowledge, of enlarging the field of her activities, and of welcoming the development of the scientific and so-called practical courses, thus keeping her, true to her high mission, in the front rank in all branches. I heartily congratulate the University of Edinburgh upon to-day's acquisitions, from which I hope are to come worthy successors of Faraday, Lockyer, Becquerel, Curie, Rutherford, Rayleigh, Ramsay, Mendeléeff, Kelvin, Tait, and others, to give her such fame in science as the names of Hume, Carlyle, Dugald Stewart, Hamilton, Chalmers, Simpson, and others have already conferred upon her in other fields of knowledge.

CON

AGRICULTURAL NOTES.

ONDENSED Vegetable Milk.-Mr. T. Katayama, a writer in a recent issue of the Bulletin of the Agricultural College, Tokyo (Bulletin, College of Agriculture, Tokyo Imperial University, vol. vii., 1, April, 1906), describes the preparation of condensed vegetable milk, a product which, though not yet in commerce, would appear to have possibilities for tropical countries. The Japanese prepare vegetable milk from soy beans by soaking, crushing, and boiling in water. The liquid obtained is said to be very similar in appearance to cows' milk, but it differs widely in composition. The average composition of soy milk is given as -water, 92.5 per cent. ; protein, 3.02 per cent.; fat, 2.13 per cent.; fibre, 0.03 per cent.; nitrogenfree extract, 188 per cent. ; ash, 0.41 per cent. To this material Mr. Katayama added sugar and a little dipotassium phosphate, the latter to prevent protein separating out; he then evaporated the mixture, and obtained a condensed milk. This product is described as having a yellowish colour, an agreeable taste like cows' milk, but a slight odour of beans. It is recommended for culinary purposes as a cheap substitute for ordinary condensed milk.

Cherry Leaf Scorch.-Mr. E. S. Salmon, mycologist at the South-Eastern Agricultural College, Wye, directs attention (Journal, South-Eastern Agricultural College, Wye, No. 15, July) to a danger which threatens the cherry growers of Kent. For the past few years the cherry leaf Scorch (Gnomonia erythrostoma) has been gradually obtaining a footing in the county. In 1901 Dr. Carruthers pointed out the dangerous character of this disease, but his warning, we are informed, was "wholly disregarded." During the past spring Mr. Salmon visited all the districts in which diseased trees were reported, and he publishes a map showing that leaf scorch now occurs in many orchards from Sevenoaks on the west to Selling on the east, and from Tunstall on the north to Pluckley on the south. It has thus already reached the borders of the Sittingbourne and Faversham districts, and with the next favourable season it will probably invade the valuable orchards in these important cherry-growing centres. The disease is easily detected. The young leaves are infected in spring, and in summer the leaves shrivel up and look as if they had been scorched. They do not fall off in winter, but persist until the following season, forming

plague centres from which the young leaves are infected as the buds open. The only thoroughly effective remedy is the collection and burning of dead leaves; it is a costly process, but by this means the disease was banished by Prussian fruit growers after it had devastated some of their best orchards. Mr. Salmon also recommends the use of Bordeaux mixture in spring to render the young leaves proof against infection, and he is experimenting with this mixture in orchards near Pluckley; but he remarks that unless growers cooperate in fighting the disease there is little chance of getting rid of it.

Prussic Acid in Fodder Plants.-In vol. i., part iii., of the Agricultural Journal of India, Dr. J. W. Leather gives some particulars about the occurrence of prussic acid in fodder plants. It is well known to the Indian ryot that a feed of green jowari (Andropogon Sorghum) occasionally proves fatal to cattle, while in recent years stock-owners in this country have now and again been startled by cases of poisoning arising from the use of imported beans. It is only within the past year or two that the cause of such mysterious cases of poisoning has been explained. Certain plants contain glucosides which, when acted upon by a particular enzyme, produce prussic acid. Of such plants Dr. Leather mentions, in addition to Andropogon, flax, the two common beans Dolichos lablab or val and Phaseolus lunatus, the Rangoon bean, and the tapioca plant. The ferment is present in the plant, but, except conditions favourable to its activity occur, no prussic acid is formed. Hence it happens that a food, which is usually quite wholesome, may suddenly develop poisonous qualities. Dr. Leather analysed some green jowari, which had been fed to cattle with fatal results, and found in it 1-25 grains of prussic acid per lb. of green fodder. Analysing the same crop a month later, he found that the poison had diminished to 0.75 grain. This is in accordance with the ryot's experience; he is most afraid of young jowari. The leaves were found to contain much more prussic acid than the stalks, and ten times as much as the inflorescence.

Artificial Manures for India.-In connection with the possible introduction of a sulphuric acid industry into India, Mr. F. G. Sly, I.C.S., contributes a note on mineral fertilisers to the Agricultural Journal of India. He quotes experiments which show that soluble phosphatic manures would be of great value in Bengal, and he indicates that a demand for such manures may arise in India before very long. The native sources of mineral phosphates are not particularly promising, but it is suggested that Christmas Island phosphate, which can be landed in Calcutta for about 50s. per ton, would supply suitable raw material for the Indian manufacturer of superphosphate of lime.

Agriculture in Egypt.-The bi-monthly Journal of the Khedivial Agricultural Society of Egypt has given place to a year-book, and if subsequent issues maintain the promise of the first number former readers of the journal will appreciate the change. The first (1905) volume of the new year-book, which has recently reached us, is a wellprinted, well-illustrated royal octavo book of 277 pages. It comprises two sections, the first contributed by officers of the society, the second by members of the staff of the Khedivial School of Agriculture. The greater part of the volume is devoted to the cotton crop. The first paper, by Mr. F. C. Willcocks, deals in detail with the cotton-worm, the larva of the moth Prodenia littoralis, which appeared in Egypt about forty years ago, and for thirty years has done serious damage. The Government has now adopted stringent measures in the hope of ridding Egypt of this plague. All cultivators are required to notify its appearance, and to collect and destroy the eggs at once. larva damages the plant chiefly by feeding on the undersurfaces of the leaves, but it also attacks the buds and young bolls. This insect is very prolific, and there may be seven generations in a season. In a second paper Mr. Willcocks gives a very complete account of the cotton bollworm Earias insulana, which is the destructive boll-worm of Egypt as well as of India. For this pest no effective remedy has yet been found. The cotton cut-worm Agrotis ypsilon is also described and figured. The secretary of the society, Mr. G. P. Foaden, writes a general article on the selection of cotton seed, and directs attention to the methods in use in the United States of America. Of the

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