Apj<il 1 1, 



'»95] 



NATURE 



573 



SCIENTIFIC SERIALS. 



The Mathimalual Gazette, No. 4 (Macmillan).— This is the 

 firsl number of the- enlartjed series. We are glad to find that 

 the suiiport accorded i') che first year's issue has been sufficient 

 to warrant this enl.Trgement ; hut to make the Gazette a success, 

 and not a drag upon the fund-; of the Association, it is impera- 

 tively necessary that a much larger measure of support should 

 be rendered by the general body of ma hematical teachers 

 The opening paper is one on al^e'ira in schools, which was read 

 before the Associition at its annuil meeiing in January of this 

 year. In this article the author, Mr. Heppel, drawing upon his 

 wide experience as a ' coach," sla'es that when tmpih have come 

 to him he has found that the work in algebra has usually to be 

 done all over again. The reason of this appears to him to be 

 " the ever-growiiiiT divergence there is between the conception 

 of the nature and objects of algebra that dominates school 

 teaching and the conception that regulates the application of 

 algebra to more advanced maihematici." Many of the sugges- 

 tions are likely to be useful, and we commend them to the 

 notice of our brethren in the craft of teaching. —Mr. T. Wilson 

 contributes a note on mathematics for astronomy and navigation, 

 in which he suggests that the elements of spherical trigonometry 

 might occupy a more prominent pUace in school teaching than 

 they do, and to cover all ages he winds up with, *'let no one 

 <lespair that he is tooold for mathematics." — Mr. Rouse adds a 

 secoi'd chapter to his previous interesting article on conies. — 

 "SomedM text-books" is a review of John 

 Ward's "The Young Mathematician's 

 Guide" (1747), by Mr. J. H. Hooker, 

 which brings before us matter that was 

 served up for the food of students in the 

 time of "good Queen Anne." The rest 

 of the number is taken up with more ex- 

 tended ariicles (than bcfoe) entitled notes, 

 solutions, new (^urstions, and litles of new 

 books. These latter pag s should be of 

 general interest, a.; they are likely to be 

 useful both to students and teachers. 



Bulletin of the American Mathematieal 

 Soci/ly, ■O'ics 20, vol. i. No, 6, March 

 1895. — The notice of "Arthur Cayley," 

 pp. 133-I41, whiih opens ih s nimber, is 

 a warm appreciaii m ol the clia acier and 

 writings of our great m.ithcmatician, by 

 Dr. Charlotte Scott, and is due to her 

 "intense ad i.iratioit for his work and 

 personality, and to the fact that for the 

 last fourteen years" she has ** been 

 privileged to know him and experience 



his kindness," It is the fullest account we have yet read, and 

 h-is manv m ire points of imcrest for an Englishman than Sijjnor 

 Brioschr's ilo^e, which i- naturally cont'rned more closely to an 

 apprtciaion of los mathemancal work. One extract we must 

 make : — " Any sketch of Prof. Ca> Icy is self-condemned if it 

 leaves out ol account the child like purity and simplicity of his 

 nature, the entire freed'^m from the professional touchiness on 

 the score of priority to which mithematiciani arc as liable 

 as other men. He was ever ready to ray what he was 

 working at, to in licate the lines of thought, to state 

 what difficulties he i»as encountering . . . fiut his great- 

 ne s and his simplicity cinnot be enshrined in anecdotes. 

 — Prof. Osgood (pp. 142-154) m " Tne Theory of Functions," 

 analyses, chap'er Ity chapter. Or. (now Prof.) Forsyth's brilliant 

 work on "Tne Theory of Functions of a Complex Varialde," 

 and winds up thus : — " The tiook is not one thn can sa'elv be 

 put into the hands of the immature student for a first iniiodu;- 

 tion to the study of the theory of lunciions. But the student 

 who is already famili ir wi h the elements, and who has acquired 

 some degree of CI i ical power, will find its pages incentive to 

 valuable work in this wide fie d." — A sh Tt no e fnlUiws on the 

 inlroductii n of the notion of hyperbolic functions, by Prof. 

 Haskell, wfiiih wrs rearl bef»re the Society at its Dtceiiiber 

 (■894) imeing. — The second summer meeting of the Society is 

 to be held at Springfield, Mass , on August 27. 



Inlet nationalfS Arthivfiir Ethno^raphie. Ifand vii. Heft iv. 

 1894. This pan cimiiuencc^ wiih a long an! thorrmgh study 

 (in Oermnn) on t' e hair-cutiii g cu-loms of 'he Southern Slavs, 

 fcy Fricdiich S. Kr.iuss. Several songs are reproduced in the 



NO. i3-;8, VOL. 51] 



original, which are also translated info German. In this study 

 two elementary ideas of mankind are met with, but imbued 

 with the local colour of the Southern Slavs, and varied in tint 

 according to the stage of culture. Hair cutting is a means of 

 adoption into kin-hip, and also as a redemption from ihe sacrifice 

 of the liody or life to the spirit of disease. It is a rite per- 

 firined for social obligations and for good luck. — Prof. P. J. 

 Veth concludes his exhaus'ive account (in Dutch) of the Man- 

 drake, which is a valuable contribution to signature-lore or 

 sympathetic magic. The most interesting of the " Notes" is 

 an illuslraled communication by A. Herrmann, on the cupping 

 and blood-letting appliances of the wandering gypsies. 



SOCIETIES AND ACADEMIES. 



London. 



Royal Society, March 21.^" On the Diselectrification of 

 Air." By Lord Kelvin, P.R. S., Magnus Maclean, and 

 Alexander Gait. 



§ I. The experiment describerl in § 14 of our paper on the 

 " Electrification of Air and other Gases by bubbling through 

 Water and other Liquids" (Roy. Soe. Proc, February 21, 

 1895), proves that air, electrified negatively by bubbling 

 through water and caused to pass through a metallic wire gauze 

 strainer, gives up some, but not a large proportion, of its 



J/i Melrc.-i 



Fig. 



electricity to the metal. We have now made a fresh experi- 

 mental arrangement for the purp ise of investigating di. electri- 

 fication of air which has been electrified, whethT p tsiiively or 

 negatively, by other means than bub'iling through water ; with 

 apparatus represented in Figs, i and 2, which is simplified from 

 that of our former paper by the omission of the apparatus for 

 electrification by bubbling, and for collecting large quantities of 

 electrified air. 



§ 2. In Fig. I, A B represent the two terminals of a Voss 

 electric machine connected, one of them to a metal can, c c' (a 

 small biscuit canister of tinned iron), and the other to a fine 

 needle, of which the point « is in the centre of the can. The 

 wire making the connection to the needle parses through the 

 centre of a hole in the side of the can, stopped by a paraffin 

 plug. Air is blown from bellows through a pipe, E, near the bot- 

 tom of the can, and allowed loescipe from near the top through 

 an elec ric filter, F, called the tested filter, from which it passes 

 '.hrimgh a long block-tin pipe, c G, about 3* me'res long and 

 I cm. internal diameter, and thence through a short tunnel in 

 a block of paraffin, K. From this, lastly, it passes through a 

 seconil electric filter, R, into the open air. This second filter, 

 which we sometimes call the testing filter, sometimes \heeleetric 

 receiver, is kept in metallic connection with the insulated 

 terminal, I, of a quadrant electrometer, 0. The metal can and 

 the block tin pipe are metallically connected to the outer case 

 and uninsulated terminal, T, of the quadrant electrometer. 



§ 3. The testing filter or electric receiver consi^ls of twelve 

 di-cs of brass-wire cloth fixed across the mouih of a sho't metal 

 pipe supported on the end of the paraffin tunnel in the manner 



