October 28, 1915] 



NATURE 



249 



measurement of the flow in a pipe. The main pipe 

 is by-passed at a point on the tube and at the con- 

 tracted portion of the Venturi, and an ordinary small 

 water meter is placed in the by-pass. It is shown 

 both by calculation and experiment that the ratio of 

 the volumes of water flowing" by the two paths is con- 

 stant to within i per cent, for varying rates of flow, 

 and hence that the small meter can be graduated to 

 give the total volume of water flowing through the 

 main pipe. — Albert Colson : The heats of saturation of 

 some alkaline salts. — Maurice Drapier : The applica- 

 tion of cryoscopy to chemical analysis. — Em. Bourque- 

 lot and A. Aubry : The activity, in the course of the 

 biochemical synthesis of the /?-glucosides by ^-gluco- 

 sidase, of the other ferments which accompany it in 

 the emulsin. 



Washington, D.C. 

 National Academy of Sciences (Proceedings, No. lo, 

 vol. i.). — G, G. MacCurdy : The octopus motive m ancient 

 Chiriquian art. After discussing general features of 

 animal motives in Chiriquian art, the octopus motive, 

 which appears hitherto not to have been identified, 

 is traced through a number of varying forms in vases, 

 of which six are figured in cuts. — Rh. Erdmann : The 

 life-cycle of Trypanosoma brucei in the rat and in rat 

 plasma. The method employed affords the means of 

 following, outside the body of the host, the sequence 

 of changes in the life of trypanosomes, and its use 

 has shown dimorphic forms, latent or round, and 

 crithldia-like forms in Trypanosoma brucei outside of 

 the host.— P. W. Bridgman : The effect of pressure on 

 polymorphic transitions. This note presents, in a com- 

 pact form by means of diagrams, many of the essen- 

 >tial facts concerning the effect of high hydrostatic 

 pressure on the polymorphic transitions oT thirty sub- 

 stances. — G. M. Green : Isothermally conjugate nets of 

 space curves. A necessary and sufficient condition 

 that a conjugate net of curves on a surface be iso- 

 thermally conjugate is that at each point of the sur- 

 face the pair of axis tangents, the pair of associate 

 conjugate tangents, and the pair of anti-ray tangents 

 be pairs of the same involution. — P. D. Lamson : The 

 role of the liver in acute polycythaemia. There is in 

 the body a mechanism for regulating the red corpuscle 

 content of the blood ; this mechanism is under nervous 

 control, responding to nervous, chemical, and 

 emotional stimuli ; the adrenal glands play a part in 

 this mechanism, and the liver is the seat of the changes 

 which increase the number of red cells, partly bv a 

 reduction in plasma volume, and partly by bringing 

 cells into the circulation which are not normally pre- 

 sent. — D. A. Maclnnes : The potentials at the junctions 

 of salt solutions. The author directs attention to the 

 fact that the liquid junction potential El of a concen- 

 tration-cell of the type 



Ag+AgCl,KCl(C,),KCl(C.),AgCl-HAg 



can be derived from measurements of its electromotive 

 force, E, and of the cation-transference number, n^, 

 with the aid of the equation E ,.JE = {2n^-i)/2n^. 

 This equation involves only the assumption that the 

 work attending the transfer from one concentration 

 to the other of one equivalent of ion is the same for 

 the cation as for the anion. The author substantiates 

 this assumption by showing that this equation, when 

 applied to the electromotive force data of Jahn, leads 

 to nearly the same values of E — E,. (which should 

 equal the difference in the two electrode-potentials) 

 whether the electrolyte be KCl, NaCI, or HCl.— R. G. 

 Aitken : A statistical study of the visual double stars 

 in the northern sky. At least one in every eighteen, 

 on the average, of the stars as bright as g-o magnitude 



NO. 2400, VOL. 96] 



in the northern half of the sky is a double star visible 

 with the 36-in. telescope. Close visual double stars 

 are relatively more numerous in the Milky Way than 

 elsewhere in the sky, and visual double stars as a rule 

 revolve in relatively small orbits. Close visual double 

 stars are rare among stars of either very early or very 

 late spectral class. — E. B. Babcock : Walnut mutant 

 in^l^estigations. The mutation takes place in female 

 flowers only, and appears in the first generation after 

 the mutation occurs, but on crossing with the species 

 type it is completely recessive in the Fj generation, and 

 the nature of the mutation is such that only certain 

 genetic factors are affected without having the chromo- 

 some number disturbed.— C. B. Davenport and H. S. 

 Conard : Hereditary fragility of bone. Of a parent who 

 early in life was affected with brittle bones at least 

 half the children will be similarly affected, but if 

 neither parent, though of affected stock, has shown 

 the tendency then expectation is that none of the 

 children will have brittle bones. 



Cape Town. 



Royal Society of South Africa, September 15. — Dr. L. 

 Peringuey, president, in the chair. — Ethel M. Doidge : 

 South African Perisporiales : (i) Perisporiaceae. The 

 Perisporiaceae and allied fungi are very plentiful in 

 South Africa, especially in forest regions and in warm 

 districts with a fairly plentiful rainfall. The speci- 

 mens in the Union Mycological Herbarium are mostly 

 from the Woodbush forests in the Zoutpansberg, from 

 the Knysna, and from the coast regions of Natal; 

 there is also a fair sprinkling from other parts of 

 the coast and from Natal as far inland as Pieter- 

 maritzburg. The Middle and High Veld of the 

 Transvaal are only represented by a single specimen, 

 a species of Dimeriella collected at Bandolier Kop. 

 All that is known of the South African Perisporiales 

 up to the present is comprised in diagnoses and de- 

 scriptions of fungi collected by Prof. MacOwan and 

 Dr. J. Medley Wood, and in a few descriptions of 

 fungi more recently collected and published in the 

 Annales Mycologici and elsewhere. All the earlier 

 work was done in the Grahamstown district and the 

 coast region of Natal, so that a large part of the 

 Union was left totally unexplored so far as this group 

 was concerned. — Alex. Brown : The arrangement 

 of successive convergents in order of accuracy. 

 One of the most important uses of simple 

 continued fractions is for the solution of the 

 problem to find the fraction the denominator 

 of which does not exceed a given integer, 

 which shall most closely approximate to a given 

 number commensurable or incommensurable. A prac- 

 tically complete solution was provided by Lagrange in 

 1769 in his paper, " Sur la Resolution des Equations 

 Num^riques" in the Memoires de VAcademie royale 

 des Sciences et Belles-Lettres de Berlin. His results 

 give the fraction nearest in defect and the fraction 

 nearest in excess satisfying the conditions. He does 

 not, however, consider the question of deciding which 

 of these two fractions is nearest in absolute value to 

 the given number. The author gives a proof of the 

 rule and a method of arranging the convergents in 

 one set so as to show the nearest in defect, the nearest 

 in excess, and the nearest in absolute value, satisfying 

 the stated condition. — Alex. Brown : The use of a 

 standard parabola for drawing diagrams of bending 

 moment and of shear in a beam uniformly loaded. 

 The important stresses in a uniform continuous beam 

 are the shear and the bending moment ; they are best 

 shown in the form of graphs where length along the 

 beam is taken as abscissa and the required function 

 as ordinate. 



