254 



NATURE 



[July 12, 1900 



the lowest point. Thus for orders i, 2, 3, the forms of the 

 solids are a cylinder ; a paraboloid of revolution, a cone. If the 

 solid of order n is suspended at a distance / from the knife- 

 blade, then when it is immersed to a depth x in liquid, the 

 moment of |the resultant upward thrust of the fluid about the 

 knife-edge is proportional to px^. The operation of solving the 

 equation consists in adjusting the weights at suitable distances, 

 A A» A fi^o"^ the axis, and balancing them, then running water 

 into a trough containing the solids until the fluid thrusts 

 balance a weight A fixed at unit distance from the axis of the 

 beam ; when this is done the equation of moments takes the 

 form of the given algebraic equation and x, the root of the 

 equation is equal to the depth of immersion of the solids. 



In the Rendiconto del R. Istituto Lombardo, xXxiii. II, 12, 

 Prof. Luigi Berzolari considers a generalisation of the problem 

 enunciated by Tanturri, of discovering the number of conies 

 meeting a given algebraic gauche curve in eight points. The 

 generalisation consists in the problem of finding the number of 

 conies meeting one or more given algebraic curves in a points, 

 passing through b given points and touching c given planes, 

 where a + 23 -f^ = 8, and a number of results are given referring 

 to the particular cases when one or more of the algebraic curves 

 are straight lines. 



Although it is now about sixty years since Moser published 

 the results of his experiments on the action of light upon various 

 surfaces as revealed by the condensation of vapours upon them, 

 the character of the change produced by light still remains a 

 mystery. Theories have been suggested, guesses have been 

 made, but little or nothing has been proved. Major-General J. 

 Waterhouse, I.S.C., has, during the last year, accumulated 

 some additional interesting facts in connection with this subject. 

 He fully confirms Moser's results as to the production of a 

 change on the surface of metallic silver by exposure to light that 

 can be demonstrated by 'the condensation of a vapour, such as 

 mercury upon it. But he has gone further, and demonstrated 

 the change by the deposition of silver from solution, after the 

 manner of the development of an exposed wet collodion photo- 

 graphic plate. By some half hour's exposure in bright sunshine 

 "printed out" images were obtained, that is, images visible 

 without any subsequent application of a developer. General 

 Waterhouse shows that these results are not due to pressure 

 against the mask or stencil plate used, nor to the emanation 

 of vapours from it, nor to heat. Usually blue light gives a 

 much stronger effect than red, but in one experiment when the 

 exposure was for three hours to bright sunshine, the effect was 

 reversed, and the patches under red, orange and yellow glasses 

 were developable, while those under the blue and violet glasses 

 were not. But when the silver plate was heated to redness, 

 quenched in dilute sulphuric acid, washed and dried, and the 

 cut out design was also warmed before use, the effect produced 

 by light was so small that it seems doubtful whether there was 

 any effect at all. On the other hand, if the silver plate was 

 exposed to the fumes of certain substances, especially nitric acid, 

 it was rendered very much more sensitive. General Waterhouse, 

 in his communication to the Royal Society, states that he hopes 

 to continue the investigation this summer, and invites others to 

 extend the observations that he has described. 



In the course of the Cavendish Lecture on the "Application 

 of Pathology to Surgery," recently delivered by Mr. H. T. 

 Butlin, of St. Bartholomew's Hospital, to the West London 

 Medico-Chirurgical Society, a good deal was said with reference 

 to research work, especially in relation to pathology. In the 

 course of the lecture the need was pointed out of two species 

 of pathological laboratories for research — one for research in pure 

 pathology, without any reference to its application, which 



NO. 1602 VOL. 62] 



" need-Jiot- be attached, so far as its site is concerned, to any 

 hospital. The other for research in applied pathology, the 

 laboratory for inventors, must needs be attached to the hospital ; 

 and those who work in it should have the freest access to the 

 wards, even if they are not in charge of special wards, and 

 should have every opportunity of observing what is done there 

 and in the operating rooms. In order that they may be 

 thoroughly instructed in the science of pathology, they should be 

 taken from among the workers in the laboratory of pure 

 pathology, and should be selected on account of their special 

 aptitude for the work of research and for the originality they 

 have exhibited. They leave the school of discoverers and the 

 science of pure pathology for the school of inventors and the 

 science of applied pathology." After alluding to the advance 

 that has been made during the last few years, the lecturer said : 

 " Money and organisation are riecessary if great results are to 

 be secured. The laboratories for research in pure pathology are 

 too small and too scattered, and insufficiently endowed. The 

 laboratories in the hospitals, which ought to be devoted to 

 applied pathology, are used for every kind of microscopical and 

 bacteriological examination and for teaching, so that research is 

 crowded out. And pathological chemistry, from which vast 

 things are to be hoped in future, has taken no proper hold upon 

 the town." An investment of funds for the advancement of 

 medicine and surgery, something like the provisions made in 

 certain industrial establishments in Germany for research, was 

 needed, in the opinion of the lecturer, who had no doubt as to 

 the advantage which would accrue from such a movement. 



In No. 6 of the Ttifts College Studies appears an impoj^ant 

 paper, by Mr. J. S. Kingsley, on the ossicles of the ear, which 

 concludes with a suggestive discussion on the origin of mammals. 

 In regard to the latter part of the subject, the author, as might 

 be expected, attaches much importance to the fate of the 

 quadrate bone of the lower vertebrates in mammals. And he 

 arrives at the conclusion that the incus is mainly the represent- 

 ation of that element, although a portion of the latter may be 

 included in the tympanic ring. It is further urged that the 

 articulation of the lower jaw with the skull in mammals does 

 not correspond with the same articulation in the lower 

 vertebrates, but is entirely a new formation. 



As regards the origin of mamn^als, Mr. Kingsley urges that 

 the ancestral type must certainly have possessed a freely 

 movable quadrate bone ; from which he is led to conclude that 

 the fixed suspensory arrangement of the lower jaw found in the 

 chimseroid fishfes, Ceratodus, and amphibians, is an acquired, and 

 not a primitive, feature. Hencei the fringe-finned fishes like 

 Polyptertis indicate the ancestral stock of the higher vertebrates. 

 Reverting to mammals, it is shown that the anomodont reptiles 

 of South Africa are far too specialised to have been the parent 

 stock. From this and other inferences it is concluded that " no- 

 reptile has yet been found which will in any way fit the require- 

 ments for the ancestor of the mammalia ; but that all known 

 facts point rather to a line of descent from forms allied to the 

 amphibia." There is, however, no amphibian type which con- 

 forms to the necessities of the situation, and it is accordingly 

 necessary to go back to the common ancestor of the existing; 

 salamanders and coecilians, and of the extinct labyrinthodonts or 

 stegocephalians. In conclusion, it is stated that the ear-bones 

 negative the view advanced by Mivart as to the egg-laying, 

 mammals having developed from a separate slock to that which 

 gave origin to the other members of the class. 



Memoir 4 of the Australian Museum, Sydney, deals with some 

 of the Crustacea obtained during the trawling expedition of 

 H.M.C.S. Thetis off" the coast of New South Wales in the early 

 part of 1898. Mr. T. Whitelegge, who has been entrusted with 



