May II, 191 1] 



NATURE 



371 



activity for some weeks at least, probably for a much 

 longer period. A few inoculations of typhoid and diph- 

 theria endotoxins have been performed in the human sub- 

 ject. The inoculations cause some local reaction at the 

 site of inoculation, but little general reaction. (The endo- 

 toxin solutions were prepared by the method described in 

 Roy. Soc. Proc, B, vol. Ixxxi., 1909, p. 325.) — J. E. 

 Barnard and Dr. R. T. 'Hewlett : A method of dis- 

 integrating bacterial and other organic cells. Bacterial 

 toxins are of two kinds, extra-cellular and intra-cellular. 

 The former are excreted into the medium, e.g. beef broth, 

 on which the organism is cultivated, so that by a process 

 of filtration the organisms can be removed, and the toxin 

 is obtained in the filtrate ; but the majority of pathogenic 

 micro-organisms do not excrete their toxins, at least to 

 any e.xtent, and the toxins are retained within and form 

 integral parts of the cells of the organisms. One method 

 of obtaining these toxins is mechanically to disintegrate 

 the bacterial cell, so that the cell contents are expressed, 

 and the apparatus here described accomplishes this. It 

 consists essentially of a containing vessel, in which, by a 

 suitable rotation of steel balls, the organisms are crushed. 

 The principal conditions to be fulfilled in such an appliance 

 are : — Approximately every cell should be brought under 

 the grinding action. Little or no rise of temperature 

 should take place. The disintegration must be carried out 

 in a vessel which is sealed, so that, when dealing with 

 pathogenic organisms, none can escape at any stage of 

 the process. These conditions are, in the main, complied 

 with in the apparatus described. Experiments indicate 

 that by this method the cell-juices are obtained unaltered, 

 and suitable for investigations on the chemical composition 

 and properties of the bacterial proteins and other cell con- 

 stituents. Also that, after the grinding process has been 

 carried on for a sufficient time, practically no cells remain 

 which can be properly stained by any recognised bacterio- 

 logical method, and which therefore can be regarded as 

 whole cells containing a normal quantity of cell-juice. 



Physical Society, April 28. — Prof. H. L. Callendar, 

 F.R.S., president, in the chair. — Prof. E. Wilson : High- 

 tension electrostatic wattmeter. When using the electro- 

 meter as a wattmeter it is necessary (in order to secure 

 accuracy) that the voltage impressed upon the quadrants 

 shall not be less than a certain minimum depending upon 

 the voltage to be impressed upon the moving system. 

 When the latter voltage is of the order 10,000, the quad- 

 rants require a voltage larger than can economically be 

 provided by a shunt. One is led, therefore, to consider 

 intensifying devices. The "series" or "current" trans- 

 former, the secondary winding of which is closed on a 

 non-inductive resistance, can be used to give fairly good 

 results, but it is not accurate at all frequencies, and is 

 dependent upon wave form. The author's quadrature 

 transformer is a very simple piece of apparatus which can 

 be relied upon to give for electrostatic wattmeters an 

 electromotive force which is strictly the differential of the 

 current in the primary winding. When so used it is 

 necessary, for accuracy, at all frequencies and on all wave 

 forms, that the integral of the mains voltage shall be 

 impressed upon the moving system, although for sine 

 curves only the difTerential need be impressed instead of 

 the integral. — Dr. R. S. Willows and T. Picton : The 

 behaviour of incandescent lime kathodes. Wehnelt has 

 shown that incandescent lime emits a large number of 

 negative ions ; if, therefore, hot lime is used as the kathode, 

 a discharge may be obtained in a vacuum tube with 

 P.D.'s so low as 30 volts. The alteration with time of 

 these kathodes, under continued use. has been investigated 

 and the following results obtained : — {i) When lime is 

 heated on platinum foil, so far from showing fatigue, it 

 actually increases in activity. With P.D.'s greater than 

 the saturation voltage this increase may be nine-fold. At 

 lower voltages a slow but steady increase up to 100 per 

 cent, has been found. The steady activity falls when the 

 lime is cold ; the initial activity may greatly increase. 

 (2) When the lime is heated on nickel foil, if the tuDe 

 carries a heavy discharge, the current increases to a maxi- 

 mum and then decreases. A greatly increased activity is 

 frequently shown after the lime has been cold for some 

 hours. At the lower voltages the same general variations 

 are shown as with platinum. (-C\ Cireat irregularity is fre- 



NO. 2167, VOL. 861 



quently shown when the current is first started ; at this 

 stage other causes than temperature, such as mechanical 

 vibrations, greatly influence the emission of ions. — Dr. S. 

 Marsh and W. H. Nottage : The formation of dust 

 striations by an electric spark. The formation of dust 

 striations by electric spark has been investigated by many 

 observers. The paper attempts to explain their formation 

 as being due to hydrodynamic forces existing between the 

 dust particles while the wave motion is passing over them. 

 The application of this theory to the striations in a Kundt's 

 tube has been made by Koenig and Robinson. The wave 

 motion is assumed to be of the spherical progressive type, 

 and expressions are obtained from the intervals between 

 consecutive striae and the distances of the striee from 

 origin. Measurements were made of stria; formed on a 

 glass plate with vertical central spark. The agreement 

 between theory and experiment is within the experimental 

 error. Experiments with channels of various shapes were 

 made. Illustrations of the various striae patterns obtained 

 with small obstacles and reflecting surfaces are given, and 

 the use of these as a convenient means of indicating 

 reflecting interference and diffraction of sound waves is 

 pointed out. — Prof. E. Wilson and L. C. Budd : Previous 

 magnetic history as affected by temperature. 

 Paris. 

 Academy of Sciences, April 24. — M. Armand Gautier in 

 the chair. — M. de Forcrand : The hydrates of potassium 

 fluoride. The results of determinations of the solubilities 

 and heats of solution of the fluorides of the alkalies and the 

 alkaline earths are given. In addition to the hydrate 

 KF.2H.jO already known, the properties of a new 

 hydrate, KF.4HjO, are described.— G. Tzitz^ica : Certain 

 conjugated networks. — Francesco Severi : The simple in- 

 tegrals of the first species attached to an algebraic surface. 

 — Henri Villat : The determination of certain discontinuous 

 movements in fluids. — L. Hartmann : The mechanism of 

 the permanent deformation in metals submitted to exten- 

 sion. The metal bar under tension is polished on one face, 

 and this repolished at intervals during the gradual increase 

 of the load. The method gives valuable information on the 

 changes taking place in the bar above the elastic limit. — 

 G. A. Hemsalech : Some spectral phenomena accompany- 

 ing the displacement of the spark by a magnetic field. A 

 study of the spectrum of the spark between calcium elec- 

 trodes in a magnetic field, the metal poles being in an 

 atmosphere of hydrogen. The spectrum obtained ap- 

 proaches that observed in the upper layers of the chromo- 

 sphere of the sun. — M. Qutton : Experiments on the 

 velocity of light in refractive media. In a preceding note 

 the author has described a method for the comparison of 

 the velocities of propagation of Hertzian waves and light 

 in air. The same apparatus has now been applied to the 

 measurement of the ratio of the velocities of light in air 

 and liquids. These results are compared with the indices 

 of refraction determined in the ordinary way, and the 

 differences are shown to be in accord with the theory 

 developed by M. Gouy in his memoirs on the propagation 

 of light in media possessing dispersion. — M. Guilleminot : 

 The intensity and quality of the X-rays diffused by 

 aluminium plates of varying thickness (secondary rays). — 

 Georges Baume and Georges Pamfll : The fusibility 

 curves of gaseous mixtures, combinations of hydrochloric 

 acid and sulphur dioxide with methyl alcohol. With the 

 system methyl alcohol, hydrochloric acid, a clear mixture is 

 shown at the composition corresponding to equal molecules. 

 With sulphur dioxide two compounds are defined, 

 CH,OH,SOj and 2CH,OH,SO,.— L. Franchet : The pre- 

 paration of the black enamel of the Greek potteries by 

 means of natural ferroso-ferric oxide. The black enamel 

 of the ancient potteries was obtained with magnetite. The 

 flux for this was probably made from silica and alkali 

 salts. — D. Cauthlor : Syntheses of the secondary a-ketonic 

 alcohols. The only ketones of this type described up to the 

 present have the composition R.CH(OH).CO.R. In the 

 present paper a jrom-ral method of preparing ketones of the 

 type R,.CII(OH).CO.R,, is given. An aldehyde R,.CO.H 

 is treated with hydrocyanic acid, giving R,.CH(OI!).CN. 

 In presence of two molecules of an organo-mngnesium 

 compound R,.MgX, the alcohol ketone R,.Cn(Oin.CO.R, 

 is obtained. — .Am(^ PIctot and Alphonse Qams : The 

 synthesis of oxvberberine.— G. Darzens and J. Sojourn^ : 



