January 17, 19 18] 



NATURE 



399 



in future will be possible in the event of a peace of 

 renunciation. Anyone able to make a cool calculation 

 must answer promptly in the negative. Certainly even 

 in that case we should not collapse if we had to bear 

 our war burdens alone; but as to this one should be 

 under no illusion — ^we should then have to economise 

 ■ verywhere for these purposes, whether we liked it or 



►t, in order at least to maintain our present rate of 

 it'velopment." 



Education (No. 2) Bill was introduced by Mr. Fisher 

 in the House of Commons on January 14, and read a 

 first time. In explaining the new measure, Mr. Fisher 

 said: — "The Bill which I now introduce is substan- 

 tially identical with the measure familiar to the House. 

 It imposes upon the councils of counties and county 

 boroughs the duty of providing for all forms of educa- 

 tion. It abolishes exemptions from school attendance 

 between five and fourteen years of age. It provides 

 for further restrictions upon the industrial employment 

 of children during the elementary-school age, and for 

 the gradutil introduction of a system of compulsor}' day 

 continuation classes for adolescents. In the new Bill, 

 as in the old one, local education authorities are em- 

 powered to give assistance to nursery schools, and in 

 other ways to help the physical and social welfare of 

 the children committed to their charge. Indeed, atten- 

 tion to physical welfare is a special and distinctive 

 note of both Bills. On the other hand, I have either 

 omitted or amended certain of the administrative 

 clauses." Clause 5, which provided for provincial asso- 

 ciations, is omitted, and provisions are embodied in 

 Clause 6 which will facilitate the federation of local 

 education authorities for certain purposes, which was 

 the governing principle of Clause 5. Some alterations 

 have been made in the clauses dealing with the attend- 

 ance at continuation classes and at nursery schools, and 

 also in the clause dealing with the abolition of fees. 

 Mr. Fisher added :— " A White Paper will be circu- 

 lated so that hon. members may be able to see clearlv 

 the changes of substance introduced. I hope it will be 

 recognised that the adoption of this course will facili- 

 tate the expeditious discussion of the Bill in Com- 

 mittee. I hope that as the result of the consultations 

 and discussions which I have held with the local educa- 

 tion authorities during the last few months, a large 

 portion of the measure which might otherwise give rise 

 to acrid debate may be taken as substantiallv agreed 

 upon." 



SOCIETIES AND ACADEMIES. 

 London. 

 Rontgen Society, January r.— Capt.'G. W. C. Kaye, 

 president, in the chair.— Dr. W. D. Coolidge : A 

 " radiator " type of X-ray tube. The anticathode con- 

 sists of a block of copper faced with a small button of 

 tungsten. This is fixed to a thick stem of copper 

 which passes out through the glass neck of the tube 

 and terminates in a fin radiator. The anticathode is 

 thus kept cool and does not in consequence emit elec- 

 trons, as in the case of the earlier type of Coolidge 

 tube in which the whole of the anode speedily be- 

 comes red-hot. The new tube, therefore, so completely 

 rectifies current that when an alternating potential is 

 applied the current will onlv pass in one direction. — 

 Dr. W. D. Coolidge and C. N. Moore: The field X-ray 

 outfit of the United States Army. A petrol-electric 

 unit supplies alternating current at no volts to a 

 transformer arranged to give both high-tension and 

 heating currents for the new radiator type of Coolidge 

 tube. For simplicity of control the tube is worked at 

 a constant potential of i; in. equivalent spark-gap, and 

 the current is adjusted to 5 milliamperes for continuous 

 NO. 2516, VOL. 100] 



running of the tube or to 10 milliamperes for short 

 periods. An electrically actuated control on the throttle 

 of the engine maintains constant output. The small 

 size of the bulb, 3^ in. in diameter, enables a close- 

 fitting lead-glass shield to be employed. This is made 

 in two parts, and completely surrounds the tube, a 

 suitable aperture permitting egress of the useful rays. 



Optical Society, January 10.— Prof, F. Cheshire, presi- 

 dent, in the chair.— F. E. Lampiough and Miss J. M. 

 Matliews : Relative dispersion and achromatism. The 

 paper contained an account of an inquiry into the 

 extent of the relation between the irrationality of dis- 

 persion in glasses and the mean dispersion and dis- 

 persive power. The work consisted chieflv in the re- 

 duction of observations made by Lt.-Col. J.' W. Gilford 

 on the refractive indices of thirteen spectral lines 

 for thirty glasses. The results showed the absence 

 of any accurate relations. It was found that in - 

 general the type of dispersion of a glass is determined 

 by its dispersive power, but with a few special glasses 

 mostly requiring protection an improvement could be 

 effected on the achromatism secured by ordinary glasses 

 of similar dispersive power. The problem of the triple 

 objective was referred to. — J. Guild : A spherometer of 

 precision. The chief feature of this instrument is the 

 method employed for detecting the exact contact be- 

 tween the micrometer screw and the surface under test. 

 The micrometer terminates in a small sphere of about 

 15 mm. diameter. A microscope with a suitable 

 illuminating apparatus is mounted above, and the 

 Newton's rings surrounding the point of contact are 

 observed. By watching the behaviour of the rings 

 when the screw is brought up, the exact point of con- 

 tact is determined. The sensitivity is about one ten- 

 thousandth of a millimetre. 



Paris. 

 Academy of Sciences, December 24, 19 17, — M. 

 Paul Appell in the chair. — A. Lacroix : The forms 

 of the leucitic magma of the - Lazial volcano. 

 Fourteen complete chemical analyses of the 

 various minerals are given, and the results are 

 compared with those obtained from the rocks of the 

 Somma. — Y. Delage : The mesorheometer, an instru- 

 ment for measuring the velocity of water currents inter- 

 mediate between the surface and the sea-floor. The 

 special point of the apparatus described is a contrivance 

 for damping the effects due to the oscillation of the 

 boat.— G. A. Boulenger : The marine origin of the 

 genus Salmo. A reply to some objections of Louis 

 Roule. — M. G. Friedel was elected a correspondant for 

 the section of mineralogv in the place of the late M. / 



Vasseur.— G. H. Hardy and J. E, Littlewood : The con- j 

 vergence of Fourier's series and Taylor's series. — M. 

 Guillet : Measurement of the intensity of the field of 

 gravity. Galileo's pendulum and Newton's tube. 

 Some advantages are claimed for Newton's tube over 

 the pendulum, and details are given of the best 

 construction of the former apparatus. — Mme. E. 

 Chandon : A determination with the prism astrolabe 

 of the latitude of Paris Observatory. The mean of 

 the determinations is 48° 50' ir-2i''. This compares 

 with 48° 50' 1107", the mean furnished bv several in- 

 struments between 1851 and 1892, and 48^ 50' ii^*, a 

 more recent determination (189Q to 1901) with the 

 meridian circle. — A. Veronnet : The law of densities 

 inside a gaseous mass. A study of the densitv curve 

 of a star considered as wholly gaseous. — V. Schaflers : 

 The sound of cannon at a great distance. — H. Hubert : 

 The use of the stereoscope for the examination of super- 

 posed projections.— E. Chdneveau : A relation between 

 the refractive properties and chemical constitution of 

 fatty substances. — G. Fouqud : The separation of the 

 secondary amines arising from the catalytic hydro- 



