The

the results obtained can be most readily explained by assuming that certain bands correspond to the vibrations of positive ions.-The production of high vacua by means of liquid air: Georges Claude and René J. Lévy. arrangement is based on the absorption of gases by charcoal at the temperature of liquid air.-The acoustic properties of certain halls for speaking: M. Marage. Experiments confirming the views put forward on the resonance of halls by Wallace Sabine.-The variations of some properties of quartz: H. Buisson. Two fine specimens of quartz were compared, measurements being made of their density, coefficient of expansion, double refraction, refractive index, and rotatory power. There were distinct differences between the two specimens, all the deviations being in the same sense. It is thus clear that quartz, even well crystallised, cannot be considered as a perfectly pure substance with absolutely defined properties, or even as a homogeneous body.-The radio-activity of springs of drinking water: F. Dienert.-Some pyrophosphoric compounds : J. Cavalier. The preparation and properties of the pyrophosphoric esters of ethyl, propyl, butyl, and amyl alcohols are described. They all proved to have molecular weights corresponding to the formula R,P,O,, determined by the cryoscopic method.-Barium iodomercurates: A. Duboin. -The pure ferromolybdenums: Em. Vigouroux. In the direct combination of iron and molybdenum with the iron in excess, the definite compound Fe,Mo is formed, and no other compound containing less molybdenum appears to be capable of existence.-The influence of the ketonic and acid grouping in the same molecule: L. J. Simon.—The condensation of the acetylenic amides with phenols. A general method for the synthesis of ethylene-oxyphenol amides: Ch. Moureu and J. Lazennec.-The genesis of an iron mineral: L. Cayeux.-A preliminary note on globoids and certain granulations of seeds, resembling the metachromatic corpuscles in some of their properties: J. Beauverie and A. Guilliermond. The Khaya of Madagascar : H. Jumelle and H. Perrier de la Bathie. Reasons are shown for regarding this as a new species, Khaya madagascariensis.-Study of the variations of nitrogen and phosphoric acid in the juices of a grass plant: G. André. -The treatment of seed with copper salts: E. Bréal. The superficial sterilisation of seeds by copper solutions not only prevents cryptogamic diseases, but also causes a good utilisation of the reserves.-The heats of combustion and the composition of the bones of the skeleton of the guineapig, considered as a function of the age: J. Tribot.-The nucleus of the red blood corpuscles in birds: M. Piettre and A. Vila. The Pleistocene glaciers in the valleys of Andorra and the neighbouring high Spanish valleys: Marcel Chevalier. Contribution to the Tertiary flora of northern Morocco: Ed. Bonnet.-Observations on moving shadows at sunset and sunrise: Cl. Rozet. The phenomenon of moving shadows has hitherto been observed only during an eclipse of the sun. The author points out the conditions under which the same phenomenon can be seen at sunset and sunrise.-Measurements of the variations of the gravitation constant in the Simplon Tunnel: Marcel Brillouin. The results of atmospheric studies in the region of the trade winds: L. Rotch and L. Teisserenc de Bort.

CAPE TOWN.

South African Philosophical Society, February 28.Dr. J. C. Beattie, president, in the chair.-Rock specimens showing the occurrence of Glacial beds in the Griqua Town series of Hay: A. W. Rogers. Flattened and striated stones, the peculiarities of which can at present only be attributed to glacial agencies, occur in a hard ferruginous rock near the top of the Griqua Town series in Hay. They are of various sizes, from an inch or two up to 18 inches long. They consist of chert; a few grit pebbles are found, but as yet no granites or other igneous rocks are known from those beds; some hollows, now partly filled with specular iron, may represent limestone fragments. The boulders are scattered at wide intervals through the matrix in most cases, though gravelly grits also occur.-Under water in south-eastern Bechuanaland: A. L. Du Toit. The term south-eastern Bechuanaland is used as including the divisions of Mafeking and Vryburg as far westwards as Kuruman.-A set of linear equations connected with homofocal surfaces: Dr. Thos. Muir.

DIARY OF SOCIETIES.

MONDAY, APRIL 23.

SOCIETY OF ARTS, at 8.-Ivory: Alfred Maskell. VICTORIA INSTITUTE, at 4.30.-Review of Sir Henry H. Howorth s "Ice or Water": Prof. Edward Hull, F.R.S.

WEDNESDAY, APRIL 25.

GEOLOGICAL SOCIETY, at 8.-Trilobites from Bolivia, collected by Dr. J. W. Evans in 1901-1902: Philip Lake.-Graptolites from Bolivia, collected by Dr. J. W. Evans in 1901-1902: Dr. E. M. R. Wood. --The Phosphatic Chalks of Winterbourne and Boxford (Berkshire): H. J. Osborne White and Llewellyn Treacher.

THURSDAY, APRIL 26.

ROYAL INSTITUTION, at 5.-The Digestive Tract in Birds and Mammals:
Dr. P. Chalmers Mitchell.
SOCIETY OF ARTS. at 4.30.-Seistan, Past and Present: Colonel A. H.
McMahon.
INSTITUTION OF ELECTRICAL ENGINEERS, at 8.-Long Flame Arc
Lamps: L. Andrews.

MATHEMATICAL SOCIETY, at 5.30.-Perpetuants and Contraperpetuants: Prof. E. B. Elliott.-(1) A Question in the Theory of Aggregates: (2) The Canonical Forms of the Ternary Sextic and Quaternary Quartic: Prof. A. C. Dixon.-On the Question of the Existence of Transfinite Numbers: P. E. B. Jourdain.-Some Theorems connected with Abel's Theorem on the Continuity of Power Series: G. H. Hardy.-On a Sel of Intervals about the Rational Numbers: A. R. Richardson.

A TEXT-BOOK OF BOTANY.

Dr. E STRASBURGER, Dr. FRITZ NOLL, Dr. H.
SCHENCK, the late Dr. A. F. W. SCHIMPER. Trans-
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