626 



NATURE 



Prof Barretts, that the effect of longitudinally magnetising a 

 bar of iron or of increasing its magnetisation, is to increase its 

 dimensions longitudinally and to diminish them laterally so that 

 wV- olu ™? u r emams constant ; and on the other hand, from Sir 

 SriSdiSlT " S mve ? tl 8 ati0 . ns . tLat th ^ effect of increase of 

 longitudinal dimensions in an ,ron bar is to increase, and of 



ma g n a etisa tio„ ranSVer ' e dimensions t0 diminish *> longitudinal 



thJ^t ^F h °'^ S ^° With ref «*M* to steel and nickel. In 

 the case of bars of these metals, we found their Unoitudinal 

 magnetisation to be diminished by the application of longitudinal 

 pull, and Prof. Barrett has found that oars of the same me "is 

 .WafeY ShOTteni "^" their longitudinal magneton is 



r Jl A f e CaS l°, f C0balt ' however . the results do not agree. The 

 resu ts for cobalt, given in Sir W. Thomson's paper, are some' 

 what anomalous but they refer only to ,he effect of stress on 



Uieno e rH ,n v, b T Which had b -n P^viously magneti edanS 

 then placed while ben g experimented on, under the influence of 

 *e earth's vertical force The results were therefore complicated 



thfe e'retTt f 'Sf T °" " ,e ^^ ™%™™- So fafat 

 Prof 2SJSJ 1 ' h f ey „ bear out . to some «<ent those found by 

 Prof. Barrett, but further experiments, the results of which have 



slrL¥ZT^ h Tl' Prm ? that the effectsof *r* S arethe 

 £*l£ forces • " the CaSe at ' eaSt f ° r a " but low ma g" 



„f I h , e J ehaVi0U / ° f C0ba ," and nickel throughout a wide range 

 of magne using forces, and under the influence of both transverfe 

 and longitudinal stress, will, it is hoped, be fully investigated in 

 ^continuation of Sir William Thomson's expeHmenlsf begun 

 some time ago, and temporarily interrupted by other, and for 

 refuuS! g ' m ° re preSsi " g work ' but now ab0 «' "o be 

 NwZ ™" lion . that *T brother and myself pointed out in 

 EdiW T X V"\ P ' I 29 ' the a PP licabilit y of a modification of 

 sion^ Lnl J? ° ' ne , mt ' a -'"'enient of the changes of dimen- 



sions produced n a body by magnetisation. We s ill think .hat 

 this is perhaps the most simple method, and we have found i 

 very sensitive for qualitative results. In our trials of it ve have 



wo P uTd ,e re C rlraTe ^"V 0b *&* * Carb "" butt0 " »** 

 resistant , i f ll S bee " fub J ected t0 stress to the same 



resistance as before. The experiments of Prof. Mendenhall 

 however, S how that the kind of carbon used by Ed o m hs 

 Tasimeter possesses this property in perfection; and we hope 

 soon by the use of this carbon to obtain quantitative results. 

 T i a r,, . ... Andrew Gray 



The Physical Laboratory, the University, Glasgow, 

 October 19 



[Oct. 26, 1882 



Royal Victoria Coffee Hall, WatoKoaTs.E^OcX 



Aurora 



tIie A i , S a h'Tns f WaS Tr n at , Cro > don " about 7 P.m. on Wednesday, 



the iMh nst. Three streamtrs cf a whitish colour could be 



raced d.st.nctly across the whole of the ; ky while the moon was 



up ' A. E. Eaton 



The Victoria Hall Science Lectures 

 The popular science lectures at the Victoria Hall have proved 

 quite sufficiently successful, so far, to make the manners wish 



to continue them, provided that the kindness of conn efent lee 

 hirers makes it possible to do so. There have bee and ences 



"g Ji'fhold t Ut i 600 - 5 '^ 11 C ° mpared Witb «*S the as 

 ingu ill hold, but not amiss for a Friday night, in a neighbour- 

 hood where (except on Saturdays) people think twice before 

 spending a penny. Those who have been present LreTn 

 describing the audience as a peculiar one, for whom greate^m" 



a P nd L ,S fr neCded tha 'r f0r the audiences of '"echanic? , ti u"=, 

 and the frequenters of penny science lectures in general. They 

 arc quite ready to attend and to be interested, and do no' t . nk 



outaTtoth °t, g * Pr ° Vided Ule ba " ' S "ept constantly moWnt 

 •nnaAtn, h y 'T VC1 ' y eMCt S» and anv breakdown of the" 



apparatus, however temporary, places the success of the lecture 



S a ,v°,L e" 8er h ThCre are ltam ' W and wUs,leS of 5>2££ 

 at any pause such as must occur in adjusting experiments but 

 these cease the moment the lecture proper proceeds This in, 

 S C to P th^r keS "i 16 SU ^, tained *«& of a intern mor'e 

 experiments " ^ "^ V " ied but ^tennittent 



It is to be wished these lectures could be more widely known 



THE TYPHOONS OF THE CHINESE SEAS ' 

 'pHIS work by the learned director of the Zi-Ka-Wei 



the re gl ons swept by the typhoon. The typhoons of 

 .880 amounting to fourteen, were described^ Fa her 

 Dechevrens in a previous paper. These two naner/ 

 from the greater fulness and accuracy of their deUils' 

 &£ZZ%SL« C ° nSiderable im P— ette 

 An examination of the tracks of these thirty-four 

 typhoons shows that they generally have their orifin to 

 the rone comprised between the parallels of io» and .7" 

 some of them originating in the Archipelago of the 



th^iT^' bUt t he D «™ ter number to the eastward of 

 these islands in the Pacific. The first part of their course 

 is westerly and north-westerly ; they then recurve about 

 the latitude of Shanghai, and thence followT north- 

 easterly course over Japan. During the first half of their 

 course the barometric gradients are steepest, and the 

 destructive energy of typhoons is most fully dele- 

 oped ; but after advancing on the continent, and par- 

 ticularly after recurving to eastward, they rapid y increase 

 m extent, form gradients less steep and ul 2 

 assume the ordinary form of the eye'lones o No S- 

 Western Europe. In illustration of the steepness of the 

 gradients somet.mes formed, it is stated that on July ic 



K;:? of 276 ° inches p- '» -WorUf 



Typhoons do not occur during the prevalence of the 

 north-east monsoon from November to May. In 1881 

 the typhoon season extended from May 22 to November 

 A^,'„ J 1 Japa c n e ! rue typhoon season is restricted to 

 August and September, the storms there durin^ the other 

 months resembling rather the ordinarv cyclone's of tem- 

 perate regions' The tracks of the typhoons during the 

 months of moderate temperature, May, June, the latter 

 half of September, October, and November, are the most 

 southerly ; they lie flattest on the parallels of latitude 

 and present a great concavity looking eastward ; but 

 those of the warmer months, July, August, and the 

 beginning of September, exhibit, on the other hand very 

 open curves. This seasonal difference in the form of the 

 tracks, taken in connection with the general form of the 

 recurving tracks of the West Indian hurricanes, which 

 are less open than those of the Chinese seas, suggests a 

 possible connection between the forms of these curves 

 and the different distributions of atmospheric pressure 

 prevailing over the continents at the time. 



Of the new facts brought forward in 'this report the 

 most important perhaps are those which show that the 

 typhoon tracks have the feature of recurvation as dis- 

 tinctly as the hurricanes of the West Indies and the 

 Indian Ocean. The degree of recurvation and the rela- 

 tive frequency with which it occurs in the tracks of the 

 cyclones of the Chinese seas, the West Indies, the 

 Indian Ocean near Madagascar, and the Bay of Bengal 

 respectively, are important features in the history of 

 these storms, which such reports will do much to eluci- 

 date. Vve shall look forward with the liveliest interest to 

 rather Dechevrens future reports, which from the lines 

 ot inquiry already indicated may be expected to throw 

 considerable light on the influence of extensive regions of 

 ary air and of moist air respectively, and of elevated 



The Typhoons of the Chiaese Seas 

 =cheyrens, S.J., Director of the Zi.Ka-Wi 

 1 : h-elly and Walsh, 1882.) 



vatory, Chin; 



By Marc 

 . (Shang- 



