April, 1913. 



KNOWLEDGE. 



123 



force which forms the cavity. Professor Boys has 

 facetiously suggested that this should he termed the 

 " kidney-disease " experiment. 



The manner in which a film of liquid on the 

 surface of water breaks into globules is shown in 

 Figure 123, and is best observed with dimethyl- 

 aniline. When a very small drop of this liquid 

 is allowed to trickle on to water, it spreads out into 

 a film of irregular shape, from the thin edges of 



in the centre and remain on the surface in the form of 

 rings, interspersed with plates containing several holes. 

 The surface movements described are only selected 

 examples of a large number observed by the author ; 

 and it will be noted that the indentation of the edges 

 of the globules or films is a common feature. There 

 is little doubt that these indentations arise from the 

 interplay of the tensions at work, but it is not 

 evident why an aniline globule should be uniformly 



Figurk 121. 

 Aniline globules on a. water surface. 



Figure 122. 



Movements of orthotoluidine globules on 

 a water surface. 



Figure 123. 



A film of dimethyl-aniline breaking into 

 globules. 



which a number of small globules immediately form. 

 Indentations then appear round the edges, which 

 branch out into coral-like shapes, and simultaneously 

 holes appear in the film from which similar branch- 

 ings arise. The various channels unite in numerous 

 places, thus cutting the film up into numerous small 

 portions, each of which immediately becomes circular 

 in outline; and by this beautiful process a film is 

 resolved into globules in a few seconds. In order to 

 see this remarkable movement to advantage, an ex- 

 ceedingly small drop of liquid must be used, and the 

 water must be perfectly clean tap-water. The same 

 action can be observed with qitinoline, in which case 

 the division occupies a much longer time ; and the 

 globules formed, afterafew minutes, become perforated 



indented, whilst only one side of a globule of ortho- 

 toluidine is attacked. The movements introduce 

 new features which do not appear to be capable of 

 explanation by the usual theories of surface tension. 

 It may be added that the movements may be 

 shown to great advantage by the aid of a lantern 

 provided with a horizontal stage, vessels with a 

 bottom of plate-glass being preferably employed. 

 Sufficient materials for showing the phenomena a 

 large number of times can be procured at a small 

 cost ; and when once seen it will be realised how 

 completely inadequate any verbal description must 

 of necessity be to convey to the mind the beauties of 

 the movements. Hence the writer hopes that all 

 who read will try the experiments for themselves. 



NEGRO MAN IN BRITAIN. 



UNDER the auspices of the Celtic Union, Edinburgh, a lecture 

 was delivered on the 21st of February, by W. J. Edmondston- 

 Scott, M.A., author of " Elements of Negro Religion," in the 

 Philosophical Institution, on "The Age of the Stone-circles: 

 or Negro Man in Britain." Mr. David MacRitchie, F.S.A., 

 Scotland, presided. 



The lecturer discussed the many aspects of the " pre-Aryan " 

 problem with particular reference to pre-Celtic Britain, its 

 ethnology, history and antiquities. He showed that the 

 deeper scientific researches descended into European 

 Ethnology, the more and more assertive became the Negro 

 type of physiognomy — as evidenced by the anatomical 

 characters of the oldest prehistoric skulls, — a fact which 

 argued the former existence of a negro race of Aborigines 

 in Middle and Western Europe, most probably associated 

 with a milder and more equable climate than ours; that the 

 character and contents of Cave-deposits and River-drifts 

 testified to general differences in Negro Culture; and that 



the infinite variety of Culture - stages represented from 

 Mousterian to Neolithic and later times was just such as 

 prevails universally throughout Modern India. He indicated 

 how man's antiquity in Europe resolved itself into the 

 problem of the age of India's native civilisations, whose 

 pre-historic culture in every stage and form had been diffused 

 over the European Peninsula at a very remote period ; and 

 how the Eastern origin of this negro species pointed to its 

 affinities with the Kolarian Aborigines of Bengal — the only 

 negro race in the whole Asiatic mainland — from one of whose 

 ancient tribes, now represented by the Baske, were descended 

 the Basques of Europe, as could be proved from the remains 

 ol their archaic speech and the vestiges of Kolarian culture 

 among them. On linguistic and ethnological grounds the 

 lecturer concluded thai the so-called "Pre-Aryan Problem" 

 vanished with the solution to the old-time mystery about the 

 origin of the Basques, and was one to which the scientific study 

 of the Kolarian languages offered the only means of solution. 



