r 



502 



NA TURE 



[March 26, 190; 



of the moon, to be undertaken by a system of international 

 cooperation. The Astronomer Royal and others took part 

 in the discussion on Prof. Newcomb's paper. — A series of 

 photographs presented by the Yerkes Observatory was 

 shown on the screen. The photographs were taken by Mr. 

 • ■. W. Ritchey, those of the moon with the 40-inch refractor 

 and a colour screen, and those of nebulae, &c, with the 

 24-inch reflector. — A paper by Mr. Stanley Williams was 

 read on the short period variable star UY Cygni. — Other 

 papers were taken as read. 



Anthropological Irstitute, March 10.— Dr. J. G. Garson 

 in the chair. — (1) Skulls from the Daurs' graves, Driffield, 

 Yorkshire; (2) a method to facilitate the recognition of 

 Sergi's skull types, by Dr. William Wright. Dr. 

 Wright described twenty-two skulls, fifteen being 

 those of males and seven of females. Nine of these 

 he showed were dolichocephalic, five mesaticephalic, while 

 he was in doubt as to the classification of the remaining 

 eight, owing to their precarious state. The cephalic index 

 ranged from sixty-eight to seventy-nine, and the skulls 

 evidently were those of a mixed race which was on the 

 whole dolichocephalic . According to Sergi's natural method 

 i^i of them belonged to the class Ellipsoides isocampylos, 

 seven to Isobathys Siculus, whilst the remainder were of 

 Ellipsoides ametopus, Ellipsoides depressus, and Parallel- 

 epipedoides types. The graves were of the early Iron age, 

 iron articles being found in them, and the burials being of 

 the usual simple type. As to the origin of the people buried, 

 Dr. Wright suggested two hypotheses : either they were the 

 direct descendants of the dolichocephalic Neolithic Hritish 

 or they were settlers from the Continent. In support of 

 the latter hypothesis, Dr. Wright pointed out that the 

 settlement was very near the coast, and that there were 

 two others close by, at Arras and Beverley. It was clear, 

 from the absence of weapons and the presence of women 

 and children in the interments, that the settlers were 

 ful people. On the whole he was inclined to think 

 that the people came from northern Europe and Scandi- 

 navia, which at that period were peopled by a comparatively 

 pun- dolichocephalic race. In his second paper Dr. Wright 

 explained a method for facilitating the recognition of Sergi's 

 skull types. He said that he felt the great difficulty in 

 Sergi's system was the vague definition of the types.' To 

 facilitate the recognition, Dr. Wright draws, on a photo- 

 graph of the skull, a circle the radius of which is half of 

 the maximum diameter of the skull, when the different tvpes 



cognised through different parts of the skull falling 



either within or without the circle. This method further 

 gives aid to the eye of the observer by providing a uniform 

 curve with which to compare the anterior and posterior 

 outlines of the cranium. Dr. Wright illustrated the system 

 by lantern slides showing the method as applied to the 

 different aspects of the skull. 



Royal Meteorological Society, M;nh 1?.— Captain D 

 Wilson-Barker, president, in the chair. — Mr. C. V. Boys, 

 F.R.S., gave a lecture on the transmission of sound 

 through the atmosphere. He began by contrasting the 

 apparent behaviour of waves of water, sound waves and 

 light waves with respect to physical law, and showed that 

 these were merely an effect of the relative scale of the wave- 

 length and the means of observation. He pointed out the 

 perfection of the behaviour of ripples and very small water 

 waves. There is a difficulty in making: experiments with 

 sound with apparatus smaller than houses or hills, unless 

 sound waves so short as to be inaudible are employed. Mr. 

 Boys showed the obedience of sound to the ordinary optical 

 laws. Sound waves may, in special circumstances, be- 

 come visible. By means of lantern slides the lecturer 

 showed that the air waves in bullet photographs are visible, 

 and animatograph representations were given of the shadow 

 of the sound of a great explosion, and also of Prof. Wood's 

 photographs of the reflection of sound waves. Reference 

 made to Dr. Rapp's interference observations of sound 

 waves produced by instruments and bv the voice. The 

 lecturer^ explained that light has, in a minor degree, the 

 same kind of imperfection so noticeable with sound. He 

 "included by referring to mirage and looming in optii -, and 

 stated that the corresponding phenomena in acoustics give 

 to abnormal audibility of sound. 



NO. 1743, V0L - 6 7] 



Cambridge. 



Philosophical Society, February 16. — Mr. Seward, vice- 

 president, in the chair. — On the dynamics of the electric 

 field, by Prof. J. J. Thomson, F.R.S. It is shown that all 

 the laws relating to the distribution of momentum in the 

 field follow from the view that the lines of electric force 

 carry along them a portion of the ether through which they 

 pass, the mass of ether entangled with the tubes being per 

 unit volume proportional to the electrostatic energy of the 

 field in that unit volume ; the ether thus entangled can slide 

 along the line of electric force, but as far as motion at right 

 angles to the line is concerned, the entangled ether moves 

 with the line of force, the momentum in the electric field 

 is the momentum of the ether gripped by the lines of force. 

 It was suggested that all mechanical momentum and not 

 merely electrical momentum was really momentum of the 

 ether ; the molecules of matter containing a number of 

 electrified bodies (" corpuscles "), the lines of force starting 

 from these corpuscles grip a certain amount of the ether 

 and that the mass of the body is really the mass of the 

 ether gripped by the lines of electric force starting from 

 its corpuscles. The potential energy of the field is on this 

 view the kinetic energy of the turbulently moving ether im- 

 prisoned by the lines of force. — Rust-fungi and the " myco- 

 plasm " hypothesis, by Prof. H. Marshall Ward, F.R.S. 

 The author gave a brief account, illustrated with lantern 

 slides and microscopic preparations, of that part of his re- 

 searches into the histology of rust-fungi which bears upon 

 the recent pronouncement of Eriksson, that certain cor- 

 puscules speciaux observable in the cells of the host-plant are 

 the assumed " mycoplasm " in the act of growing out to 

 form the hyphas of the fungus. The author's preparations 

 show clearly that Eriksson's corpuscules are true haustoria, 

 put forth by the hyphae of the fungus into the cells of the 

 host. Every stage in their development is traced, and since 

 the entering germ-tube, after swelling up as an infecting 

 vesicle and tube in the stomatal cavity, is found to put 

 forth one of these haustoria at a very early date, the re- 

 versed order of the phenomena assumed by Eriksson cannot 

 be accepted. — On radio-activity from snow, by Mr. C. T. R. 

 Wilson, F.R.S. An experiment of the same nature as 

 those already made with freshly fallen rain and described 

 before this Society {Proceedings, vols, xi., p. 428, and xii., 

 p 17, 1902) was made with freshly fallen snow at Peebles 

 on January 10. The snow was melted and 50 c.c. of the 

 water were evaporated to dryness in a porcelain basin. This 

 was then inverted over the thin aluminium roof of the 

 ionisation apparatus used as a detector of radio-activity 

 (described in the first of the above-mentioned papers). The 

 results give no indication of any difference in the intensity 

 of the radio-activity obtained from equal weights of snow 

 and rain. — Note on the slipperiness of ice, by Mr. S. 

 Skinner. The slipperiness of ice has been attributed to> 

 the presence of a layer of lubricating water under the body 

 pressing on the ice. The water is produced by the lowering 

 of the freezing point where the pressure is experienced. On 

 this view the object glides on a liquid layer, and consequently 

 viscous friction in water takes the place of the rubbing 

 friction between the solids. Joly has shown by calculation, 

 that the weight of a man concentrated on the blade of a 

 skate is sufficient to lower the freezing point very consider- 

 ably, and Reynolds, arguing from the difficulty of slipping 

 on very cold ice, comes to the same conclusion. In the 

 present paper it is pointed out that sliding on a liquid layer 

 is a condition under which cavitation will occur in the liquid, 

 and that this will aid the slipping. — On the rise of a 

 spinning top, by Mr. E. G. Gallop. — On automorphic func- 

 tions and the general theory of algebraic curves, by Mr. 

 II. W. Richmond. 



March 2. — Dr. Baker, president, in the chair. — On 

 the probable presence in the sun of the newly dis- 

 covered gases of the earth's atmosphere, by Prof. 

 Liveing-, F.R.S. Stassano recently pointed out that the 

 chromospheric rays measured by Deslandres and Hale 

 correspond closely with rays found to be emitted by the 

 most volatile gases of our atmosphere, and of the 330 

 chromospheric and coronal rays photographed by Hum- 

 phreys during the total eclipse of May, 1901, 200 agree 

 within one unit of wave-length with rays either of the more 



