88 



NA TURE 



[May 25, 1905 



Museum, Harvard University. In this valuable enumer- 

 ation Dr. Schellhas is very careful not to llieorise or to go 

 beyond the warrant of the manuscripts themselves. In 

 several cases he refers to diverse views concerning- the 

 names of the gods in question ; but, as he truly observes, 

 " these different opinions show on what uncertain grounds 

 such attempts at interpretation stand, and that it is best 

 to be satisfied with designating the deities by letters and 

 collecting material for their purely descriptive designation. 

 In vol. iii. of the same Papers are illustrated accounts of 

 the Cahokia and surrounding mound groups, by Mr. D. I. 

 Bushnell, and of the exploration of mounds in Coahoma, 

 CO. Mississippi, by C. Peabody. In vol. i. Mrs. Zelia 

 Nuttall gives a very interesting account of a penitential 

 rite of the ancient Me.vicans mainly derived from Spanish 

 sources. Blood was drawn from cuts in various parts of 

 the body, including the tongue and ears; the rite of 

 voluntarily drawing blood, principally from the ear, was 

 a feature of evcry-day life in ancient Mexico, and was per- 

 formed by young and old. It constituted an act of 

 humility, thanksgiving, penitence, or propitiation. 



The Survey Department of Egypt has published an 

 important paper on the rainfall of the Nile basin in 1904, 

 by Captain H. G. Lyons, director-general of the service. 

 Five years ago there were only si.x or eight places where 

 the rainfall was being measured regularly ; now, thanks 

 chiefly to the efforts of Captain Lyons, there are more 

 than forty, of which thirty-two lie to the south of Berber 

 (lat. 18° N.). He points out that to understand the 

 seasonal variation of the rainfall the relative positions of 

 the equatorial low-pressure belt, and the high-pressure 

 areas to the north and south of it at different seasons, 

 must be taken into consideration. In the low-pressure area 

 there is an ascensional movement of the air, so that its 

 moisture is condensed to form clouds and rain. This 

 ascensional movement depends upon the heating effect of 

 the sun, and it is shown month by month how the low- 

 pressure area varies with respect to the sun's position 

 from south to north, and back to south again. The care- 

 fully prepared tables and diagrams show, as a general 

 result, that the rainfall of 1904 in the Nile basin was 

 below the average ; in the equatorial regions it was some- 

 what deficient in the earlier part of the year, and above 

 the average in the autumn. 



A SOMEWH.'IT striking paper has been published by Prof. 

 Ronald Ross, F.R.S., of Liverpool University, on verb 

 functions, with notes on the solution of equations by 

 operative division {Proceedings of the Royal Irisli 

 Academy, xxv., a, 3). The writer points out that whereas 

 symbols such as / and ij> are used to denote functions in 

 general, no notation exists which can explicitly represent 

 the operation of forming any particular function of any 

 argument, apart from the argument itself, except in certain 

 simple cases as exemplified by the prefixes log, sin, &c. 

 The notation proposed by Prof. Ross meets this want. 

 It depends on the use of a purely symbolical letter ;8 to 

 denote the base of a given operation, this symbol occurring 

 in the " verb function " or operator. When this verb 

 function operates on a subject .r, it produces the result 

 obtained by writing x for /3 in the operator. For example, 

 [fl'"/"](aij = («i)'"/", [;8 log j8- l],v= V Iog.r- i, [t^ cos B]x = t'cosx, 

 and so on. Another peculiarity is the use of square 

 brackets to enclose each separate operation, the necessity 

 of which may be illustrat<;d by the following example : — 

 [(a+^)"].v represents (a + x)', whereas 



\.a + fiYx = [a + na + 0-\x-=[a + fiYa + x) = a + l,a + .x) = 2a + x. 

 NO. 1856, VOL. 72] 



In connection with inverse operations, Prof. Ross intro- 

 duces the notation of a double fraction or solidus line as a 

 distinction from the ordinary division symbol ; thus, accord- 

 ing to his notation, we should have- 



,_ ' p__ ^±v"'(^--4'"-) 



[a/32-l-i/3 + i-] 21 



as the symbolical enunciation of the expressions for the 

 roots of a quadratic equation. 



The peculiar magnetic properties of the so-called 

 Heusler's bronzes, consisting of copper, manganese, and 

 aluminium, are the subject of a paper by E. Take in 

 the Verhandlungen of the German Physical Society 

 (vol. vii., 133). The " transformation points " of a number 

 of samples of the bronze were determined, as well as the 

 effect of heating and re-heating upon them. The results 

 are shown in a series of striking curves. 



Reference has already been made in these notes 

 (Nature, vol. Ixx. p. 583) to the simple form of telescope 

 pyrometer invented by M. V6vy for measuring high 

 temperatures. This instrument is now being sold by the 

 Cambridge Scientific Instrument Co., Ltd., who have been 

 appointed sole agents for its sale in the United Kingdom, 

 the British colonies, and in the United States ; it is made 

 in two forms, a mirror pyrometer, recording temperatures 

 between 500'' C. and 1100° C, and a lens pyrometer, read- 

 ing between 900° C. and 3500° C. 



Prof. Moissan has published, in the form of a pamphlet 

 having the title " La Chimie minc^rale, ses Relations avec 

 les autres Sciences," an address delivered last September 

 at the Congress of Arts and Sciences at St. Louis. Prof. 

 Moissan, who by his own researches and those of his 

 colleagues has so widely enlarged the domains of inorganic 

 chemistry, whilst regretting that this branch of science 

 is still systematically imperfect as compared with organic 

 chemistry, emphasises the fact that during the past few 

 years its study has again resumed a place of honour. 

 This has been due largely to the discovery of the gases of 

 the atmosphere, to research at high and low temperatures, 

 the investigation of the rare earths, and to the increasing 

 tendency to the fusion of chemical and physical methods. 

 " Many important investigations still remain to be made 

 in inorganic chemistry, but for success very refined methods 

 and a high degree of accuracy will be required. Chemical 

 research must acquire the precision of physics." Finally, 

 it must be recognised that experiment is the sole guide to 

 truth, and that Faraday's saying still holds true that 

 chemistry is essentially an experimental science. 



The recent researches of M. Berthelot on tlic per- 

 meability of fused quartz vessels to gases at high tempera- 

 tures have led him to study glass from the same point of 

 view, with very interesting results. In many analytical 

 processes, and more especially in the analysis of organic 

 compounds, it is tacitly assumed that at temperatures 

 below its melting point glass is impermeable to oxygen, 

 nitrogen, and carbon monoxide and dioxide. In the current 

 number of the Coifiptes rendus, M. Berthelot gives an 

 account of some experiments on glass, the mode of work- 

 ing being the same as that used for the quartz tubes (see 

 Nature, April 13, p. 56S) with the exception that the 

 tubes were necessarily slow^ly cooled, and finds that at 

 temperatures between 550° C. and 800° C. glass tubes 

 are permeable to gases. He compares the passage of gases 

 through slightly softened glass to the gaseous exchanges 

 taking place at the ordinary temperature through the walls 

 of indiarubber tubing, and emphasises the importance of 

 this property of glass, hitherto unsuspected, in man\ 

 chemical and physical investigations at high temperatures. 



