March 13, 1902] 



NA TURE 



455 



Dr. Theiler deserves great credit for the observation, it is 

 proposed that this Trypanosoma be named after the discoverer 

 Trypanosoma TheiUri. 



Royal Microscopical Society, February 19. — Mr. W. 

 Carruthers, F. R.S., vice-president, in the chair. — The chairman 

 directed attention to an interesting exhibition, by Mr. Conrad 

 Beck, of typical bacteria. — ^The secretary, in the absence of the 

 author, read a paper by Mr. Nelson on polarising with the 

 microscope, wherein the use of tourmalines was advocated. One 

 tourmaline, of a smoky tint, with the slightest dash of pink, free 

 from veins or specks, and not less than ^-inch in diameter, should 

 be mounted in a cap to fit over the eye-piece. The other 

 tourmaline might be of the ordinary yellow-green variety, but 

 largSr, about ^a v. -^^ inch, mounted in a metal screen, 

 25 X 3i inches, so as to e.xclude all light not passing through 

 the tourmaline. This screen is to be placed in front of and 

 close to the lamp chimney. Any form of substage condenser 

 can be used with this new arrangement of tourmalines, with the 

 exception of apochromatic condensers, which should not be used 

 in polariscope work because the fluorite used in their construc- 

 tion itself polarises. The images obtained by this new method 

 will be just as critical as those in a microscope where no polari- 

 scope is used. The paper concluded with an explanation of the 

 advantages obtained in the adoption of the arrangement in the 

 investigation of phenomena due to the interference of polarised 

 light. Mr. Karop thought it would be a great advantage if a 

 tourmaline prism could be rendered effective, as Nicol's prisms 

 were expensive ; he thought, however, that a sufticiently large 

 piece of flawless tourmaline would be as expensive as a Nicol's 

 prism. 



Paris. 



Academy of Sciences, March 3. — M. Bouquet de la Grye 

 in the chair. — On an antique vase found at Abou-Roach, by M. 

 Berthelot. Contrary to expectation, this vase proved to be not 

 metallic, but appears to have been prepared by the reaction 

 between a fine sand and a mixture ot litharge and common salt. 

 — Researches on the silicide of calcium, by MM. H. Moissan 

 and W. Dilthey. As the accounts of the properties of calcium 

 silicide given by Wuhler, Chalmot and Jacobs are contradictory, 

 the authors undertook its reinvestigation. It is obtained by the 

 reaction of lime and silicon at the temperature of the electric 

 furnace, but since calcium silicide is readily oxidised oy fused 

 lime it is necessary to keep the silicon in excess. The silicide 

 obtained in this way contained only silicon as impurity, and in 

 one case this amounted to only i per cent. Calcium silicide 

 acts very slowly upon water, the reaction being complete only 

 after some months. Hydrogen is the only gas evolved, no 

 gaseous compound of silicon being produced. Hydrochloric 

 acid attacks it more rapidly, hydrogen again being the only gas 

 produced. — On the crystallisation of iron peroxide, by M. Alfred 

 Ditte. The conversion of oxide of iron into the crystallised 

 form by ignition of sulphate of iron with salt is due to the 

 combined action of the vapours of ferric chloride, hydrochloric 

 acid and sodium chloride. The action takes place still more 

 readily in the presence of fluorides, but in this case the oxide is 

 liable to be contaminated by traces of insoluble fluorine com- 

 pounds. — On a new Trypanosoma of the Bovida;, by M. A. 

 Laveran. The new species is classified as 1 r. TheiUri, and is 

 clearly distinguished from Tr. Brucei by the fact that the latter 

 is inoculable into a large number of mammals, whilst the new 

 species appears to be special to the Bovidps. It is pathogenic, 

 producing anaemia either with or without fever. During the course 

 ofthe fever the parasites maybe found in the blood for some weeks. 

 Occasionally there is pernicious anaemia with a rapid destruction 

 ofthe red corpuscles, leading quickly to a fatal issue. — New syn- 

 theses of methane, by MM. Paul Sabatier and J. B. Senderens. 

 (see p. 446). — Methane is produced by the action of re- 

 duced nickel upon mixtures of hydrogen with carbon 

 monoxide or dioxide. — On the lines of maximum decrease 

 of moduli and algebraic or transcendental equations, by M. 

 Edmond Maillet. — On entire functions and the transcendental 

 meromorphs discovered by M. Painleve, by M. Pierre Boutroux. 

 — The cooling power of air at high pressures and of air in motion, 

 by M. P. Compan. The formula expressing the law of cooling 

 as given by Dulong and Petit has Deen verified for pressures 

 below atmospheric. The author proposed to see how far this 

 formula was valid when the pressures are higher than atmo- 

 spheric, when the hot body cools in a chamber of indefinite 

 shape, and when the air is in motion. The constants of Dulong 



NO. 1689, VOL. 65] 



and Petit were found to hold up to pressures of six atmospheres, 

 and were also found to remain unchanged when the cooling 

 took place in the open instead of inside a spherical envelope. 

 The cooling effect of air in motion was found to be represented 

 by the formula kt ^hi, where u is the velocity of translation of 

 the air and / the excess of temperature. — On an electrostatic 

 relay, by M. \. Cremieu. A description of a relay which is 

 capable of automatically regulating the potential of the charge 

 on a condenser. — On the use of the capillary electrometer for 

 measuring the true differences of potential at the contact of 

 amalgams and electrolytes, by M. Lucien Poincare. A re- 

 clamation of priority against M. P. Boley. — On the search for 

 a Hertzian radiation emanating from the sun, by MM. H. 

 Deslandres and Decombe. A discussion as to the best mode 

 of attacking the problem of determining whether any of the 

 Hertzian radiations from the sun reach the lower regions of the 

 earth's atmosphere. The conclusion is drawn that the apparatus 

 for this purpose should be set up in observatories devoted to 

 physical astronomy, side by side with the apparatus for the 

 study of the sun and its atmosphere. A lengthy series of ob- 

 servations will probably be necessary before the question can be 

 finally decided. — The explanation of some celestial phenomena 

 by means of the Hertzian waves, by M. Charles Nordmann. 

 The author draws the conclusion that the sun must einit 

 Hertzian waves, this emission being particularly intense in the 

 regions where violent .superficial eruptions are produced and at 

 those times when the intensity ofthe eruptions is at a maximum, 

 that is to say, in the region of the spots and facute and at the 

 moment of maximum solar activity. This view is then applied 

 to the explanation of the form of the solar corona and the 

 spectra of comets. It is claimed for this theory that it is con- 

 tradicted by no facts, and renders a complete account of many 

 different and otherwise inexplicable phenomena. — On the re- 

 combination of the ions in gases, by M. P. Langevin. In a 

 previous note a theory has been given of a method permitting 

 of the direct measurement of the coefficient of recombination of 

 positive and negative ions. The experimental part of the work 

 is given in the present paper. It is shown that the thickness of 

 the gaseous layer and the strength of field may be varied within 

 wide limits without affecting the constancy of this coefficient, 

 which remains between 0'26 and 028, a value which coincides 

 with the determination of the same coefficient by Townsend 

 made by an entirely different method. From this it would 

 appear that in air at the ordinary pressure there is about one re- 

 combination for every four collisions between ions of opposite 

 signs. — The magnetostriction of nickel steels, by MM. H. 

 Nagaoka and K. Honda. — Remarks on the researches of 

 MM. Nagaoka and Honda, by M. C. E. Guillaume. — On the 

 expansion of steels at high temperatures, by MM. Georges 

 Charpyand Louis Grenet. The coefficients of expansion, which 

 increase with temperature, remain almost exactly equal lor the 

 different steels, the percentage of carbon in which varies from 

 o'03 to 3'5. — The specific heat and atomic weight of vanadium, 

 by MM. C. Matignon and E. Monnet. A crystalline compound 

 of aluminium and vanadium, AlVa, was prepared, and the 

 mean specific heat as determined in this and in a ferro-vanadium 

 was 0'I245, which gives an atomic heat of 6*35 if the atomic 

 weight be taken as 51. — On some thallium combinations, by 

 M. V. Thomas. — On dioxytariric and ketotariric acids, by M. 

 Arnaud. — On the products of condensation of tetramethyl- 

 diamidobenzhydrol with some primary aromatic amines in 

 which the para-position is occupied, by MM. A. Guyot and M. 

 Granderye. — New reactions of organometallic derivatives, by 

 M. E. E. Blaise. If the crude product of the reaction of mag- 

 nesium upon an ethereal solution of an alkyl iodide is treated 

 with ethylene oxide, the splitting of the magnesium compound 

 lakes place for the most part in a difi'erent manner from the 

 syntheses already published, the main product being ethylene 

 bromhydrin. At the same time, a small quantity of the ex- 

 pected primary alcohol containing two atoms of carbon more 

 than the original alkyl group is also obtained. — The action of 

 sulphides, sulphites and hyposulphites upon nitro-derivatives of 

 azo-colouring matters, by MM. Rosenstiehl and Suais. — Com- 

 pounds of alcohol with the chlorides of manganese and cobalt, 

 by M. F. Bourion. — Some facts in opposition to the application 

 without reserve of the laws of osmosis to red blood corpuscles, 

 by MM. H. Stassano and F. Billon. It is generally admitted 

 without question, as a consequence of the laws of osmosis, 

 that the volume of a red corpuscle varies inversely with the 



