392 



NATURE 



M/. 



charactfr, is capable oj ^inalysis into two characlcrs, kngth 

 .-intl thickness «( internode, which arc inherited indcpend- 

 ••ntly of one another. L. Doncaster and F. H. A. Marshall 

 ilfscribc the recults of expcrimmtn designed, amongst other 

 n .-isons, to tost the hypothesis put forward by Dr. Rumley 

 Dawson in his Causation of Sex, that thf right ov;iry gives 

 rise rxclusively to male-producing and the left ovary to 

 female-producing ova. The results do not support Dr. 

 Dawson's view. The journal is well printed and well 

 illustrated, and is of a convenient siro. ^^^• •■'-'' •? -'v .'«<!, 

 which it will doubtless achieve. 



In Milliihtngcn ntis den deutschcn Schutznibtitru, Heft 

 I, K. I.angbrrk discusses the data obtained by means of 

 sflf-rcgistering raingaugcs on the Cameroon mountain. 

 Situated near the equator, and swept by the south-west 

 monsoon winds of the west coast of Africa, almost the 

 h«avi«Nt rainfall in the world has been here recorded, 

 Debimdja receiving a mean annual rainfall of 10,140 mm., 

 and Bibundi of 10,701 mm., so far as observations go at 

 present. The article deals with the twelve months -April, 

 1909, to March, 1910, and within this period the maxi- 

 mum rainfall occurs during the forenoon in the rainy 

 season, and after midday in the dry months of the year. 

 High values were recorded from 2 a.m. to lo a.m. 

 between June and October, and from noon to 4 p.m. 

 .-ind f) to 7 p.m. between November and May. Utilising 

 the data of previous years, a general excess of rainfall 

 between 6 p.m. and 6 a.m. to the e,\tent of about 60 per 

 cent, is found, so that too great reliance must not be 

 placed on a short period only. The investigation, however, 

 is interesting, and as additional material is accumulated 

 these apparent discrepancies will doubtless be explained. 

 In the same number arc published two maps of German 

 South-west Africa, scale 1 : 200,000 and i : 400,000, which 

 include the coast region from the Orange River up to 

 lat. 26° S. A short description of the geography and the 

 meteorology of the area is also given. 



We have received from the observatory at Rio Janeiro 

 a pamphlet entitled " Codigo Mnemo-Telegraphico, " by 

 Sr. N. Duarte, chief of the meteorological section, for the 

 compilation and translation of weather telegrams, &c., by 

 the use of words instead of figures, with the view of pre- 

 venting mistakes in transmission. The principle bears 

 resemblance to the technica menioria sometimes used in 

 schools, with much advantage, for remembering dates, &c., 

 by substituting letters for figures to form words. The 

 present system is ingenious, and v^'hen the key is mastered 

 the messages may be composed or deciphered without 

 reference to the code. But it is not at all likely to com- 

 pete successfully with the intern-itional telegraphic code 

 now generally in use. 



We have received from Major R. A. Marriott 

 a pamphlet entitled " Why we may expect Warmer 

 Winters," in which he seeks to revive a theory enunciated 

 by his friend Major-General Drayson, whose scientific 

 merits he wishes should be more fully recognised. We 

 sympathise with his loyalty, but cannot accept his deduc- 

 tions. Major-General Drayson claimed to have discovered 

 a *' second rotation of the earth," and it is urged, as we 

 think somewhat disingenuously, that there is evidence to 

 show that General Drayson 's reasoning was sound, and 

 that errors have arisen in astronomical calculations from 

 neglect of the principle. The practical effects of the 

 neglect are urged as more important than the theoretical. 

 .\stronomers have assigned an erroneous value to the 

 change of the obliquity of the earth's axis to the ecliptic. 

 Instead of being limited to a quite small angle, the 



NO. 2168, VOL. 86] 



obliquity, it ii urg<-d, will change at much a« 12", re- 

 ally causing very great changes in the climate. Givet. 

 change, the result may be admitted, but inai»much af 

 annual increment i* only 40-9', and the minimum i- ■ ■ 

 reached until the y«;ir aagj, it is evident that from th^ 

 cause there can be very little effect until after 26tio n i . 

 for whatever efTect is produced in the first 3K5 years win 

 be as slowly undone in the succeeding period of equal 

 If-ngth. The author, of course, has greater scope when li" 

 applies hfs theory to geological changes, as in "• 

 of the Ice age. But here his periods seetn ' 

 short, as for the purposes of ordinary life th« • 

 long. On this point, however, we cannot insi»' 

 do not know the date of the observed phenom< n;i . 

 sufficient precision to apply calculation. Within hi'.!< r .1 

 times, the facts are scarcely borne out. If we conij ;■ 

 from General Drayson'* data, the obliquity of the e« ! , 

 at the earliest trustworthy observation, 230 B.C. wf 

 the value 24° 19' 20', while the observed obliquity ■. 

 only 23" 51' 20*; the rate of change is made, ther» f< 

 more than twice as great as that of the observed. I ■ 

 price of the pamphlet is a modest penny, but unfortunat< !> 

 the name of the publisher is not given. 



The difficulty of determining the true temperature 

 the radiating surface has been the greatest obstacle ii 

 practically all investigations of the radiating properties 

 metallic and other surfaces. A method of overcomin| 

 this difficulty is described by Mr. C. E. Mendenhall 

 vol. xxxiii.. No. 2 (p. 91), of The Astrophysical Journal 

 In his experiments the author folded a piece of thin, flat 

 conducting ribbon of, say, platinum, parallel to its length 

 so that it formed a V-shaped cavity, and found that optic; 

 pyrometer observations of the temperature within th< 

 wedge-shaped aperture, particularly in one with reflectirq 

 walls, give the true temperature of the outside surface 

 which the radiation is to be studied. Various experiirienti 

 with filaments of pure platinum verified the .1 f th 



method. 



The stability of the atom under changes of molecula 

 kinetic energy has been investigated anew by Mr. Har 

 Clo, who tested the stability by the resistance of the aton 

 to ionisation ; previous investigators have failed to fin 

 any certain dependence of atomic stability on the tempers 

 ture. A specially constructed cylinder containing hydrogei 

 or air was surrounded by an electric furnace raised U 

 various measured temperatures, and the contained gas sub 

 mitted to the ionising influence of the y rays of raditim. 

 The results, published in a paper appearing in No. 2, 

 vol. .xxxiii., of The Astrophysical Journal, indicate th;.t 

 the ionisation of air is independent of the temperature ofj 

 the gas to within 0-2 per cent., up to 600° C, and that| 

 the same independence is exhibited by hydrogen up \<m 

 about 430° C. ; a variation of above 200 per cent. iiJ 

 the absolute temperature of a gas fails to affect th«« 

 stability of the atom sufficient to change thp ionisation 

 more than about o-i per cent. 



The Bulletin of the Imperial Society of >.. 



Moscow for 1910 contains (pp. 79-212) a long math^maticil 

 investigation, by Prof. Ernst Leyst, of formulae represent- 

 ing the action of one magnet on a second. .After dealing 

 with the ordinary simple conception of a magnet as com- 

 posed of two point poles of opposite sign. Dr. Leyst con- 

 siders the much more complicated case — applicable to thin- 

 walled hollow cylindrical magnets — where each pole is rr- 

 garded as a fine circular ring of positive or negatj\' 

 matter. In the most general case the mathematical oper.-:- 

 tions are heavy, and the resulting formulae lore: ; th 



