3S 



NA TURE 



[November -o, i< 



in their manifestations. They are quite capable of giving 

 surprises. .More meteors may now precede the cometary 

 nucleus than the number there a generation ago, though 

 the period is a comparatively short one, and comprises 

 only one revolution of the swarm. There is one highly 

 favouring circumstance this year, and that is the absence 

 of moonlight. If the atmosphere is also free from cloud, 

 the nights following the 14th and 15th will aftbrd a 

 splendid opportunity both for the visual observer and 

 the photographic manipulator. 1 believe the night of the 

 14th will turn out the most productive, and especially the 

 latter part of it forming the few hours before sunrise on 

 the 15th. 



Ordinary observers, while watching the meteors, will 

 be usefully employed in determining, as accurately as 

 possible, the time w'hen the maximum in point of numbers 

 is reached. The meteors should be counted at short 

 intervals, and the horary rates of apparition during the 

 night ascertained. The position of the radiant point is 

 already well known ; a mean of seventy values places it at 

 R.A. 149' 2S', Dec. 22- 52' + , so that it is centrally within 

 the curve of the " Sickle '' of Leo, and close to the star 

 .V Leonis (Mag. 57) of Bode or Piazzi IX. 230. 



It is especially to be hoped that attempts to obtain 

 determinations of the radiant point by photographv will 

 be successful. The want of success in previous efforts 

 has been very disappointing. Thus Mr. \V H. Pickering 

 writes in Popular Astronomy, that on November 13, 1S97, 

 though he exposed eighty-one plates, only two meteor 

 trails were secured. No doubt there are difficulties to be 

 overcome ; but as soon as the photographic method can 

 be successfully utilised on a great meteoric shower, and a 

 sufficient number of trails obtained to indicate a really 

 good radiant, the visual method will have to be abandoned 

 in its favour. It will be a long time hence, if ever, that the 

 photographic plate will supersede the eye in ordinary 

 meteoric observation ; but in the case of a display such as 

 the Leonids can furnish, the new method seems to promise 

 well as regards the great accuracy of its records, though 

 hitherto the latter have been exceedingly meagre. 



W. F. Dexxing. 



MR. LATIMER CLARK, F.R.S. 



ON Sunday, October 30, Mr. Latimer Clark, F.R.S., 

 died verv suddenly at his residence at Kensington, in 

 his seventy-sixth year. His loss will be keenly felt by the 

 various learned societies of which he was a member ; 

 especially by the Institution of Electrical Engineers, who 

 claimed him as a founder and past-president. The name 

 of Latimer Clark is familiar to all who during the past 

 half-century have watched the various phases of progress 

 in the science and practice of electrical engineering. 

 Submarine cable engmeers associate it with inventions 

 that relate to every branch of their profession, from the 

 process of sheathmg the "core," to the last refinements 

 of testing : and the constructors of land-lines still recog- 

 nise the " Latimer Clark " double-bell insulator as a type 

 universally accepted His book, written in conjunction 

 with the late Robert Sabine, on " Electrical Tables and 

 Formulae," is to be found in every electrician's library, and 

 in every cable-factory and telegraph testing-station m the 

 world; his '-approx'imate method' of fault-testing on 

 submarine cables, by applying two successive potential 

 differences, was an important step in the development of 

 the modern empirical but nevertheless remarkably exact 

 system of testing by two applications of different battery 

 power ; and his test of the electrical condition of " joints ' 

 in cable core is, under the name of "the accumulation 

 method," still in daily use at cable works and on board 

 ship. Another of his valuable contributions to telegraph 

 progress is his study of the errors due to the inductive 

 action of a galvanometer-needle upon its own coil when 

 using shunts of different values, in a series of comparative 



NO. I 5 I 5, VOL. 59] 



"discharges." To this must be added his important 

 modification of Poggendorff's method of comparing 

 electro-motive forces, and the introduction, with this test 

 of the well-known potentiometer that bears his name 

 This instrument is perhaps associated in our minds rathq 

 with the laboratory than with the cable-testing room 

 and, moreover, it is here in the physical laborator] 

 that we disco\er what is undoubtedly the best-known ol 

 Mr. Latimer Clark's inventions : the zinc-mercurj 

 standard cell. The vast amount of work that has been 

 done, the modifications suggested, and the pages writter 

 in regard to this small apparatus, might well lead the un- 

 initiated to suppose that it contains some potent ialia 

 ii:ii!(ii! to which electricians are for ever looking foi 

 revelation and mysteries. It happens to be merely th« 

 electricians' practical standard of potential-difference 

 but to those who care to study such things, it is still full 

 of the mystery of the origin and meaning of contact", 

 electro-motive force. » 



The written and legendary history of the early days o^ 

 electric telegraphs, over land and under sea. shows how 

 closely Mr. Latimer Clark was associated with this work, 

 both at home and abroad. Success did not always re- 

 ward the eftbrts of the telegraph engineer, even in those 

 times : for although commercial competition did not theiK 

 exist to its present extent, there were all the difficulties of 

 inexperience to be fought against. Success as regards 

 the technical details of construction and working, camq 

 sooner than financial success. Estimating the cost o)| 

 land-lines was beset with the almost insurmountable 

 difticulties of transport and commissariat in countries 

 savage and unexplored. .Mr. Latimer Clark, in those 

 pioneer days, was one upon whom the brunt of these 

 reverses at first fell somewhat heavily. All honour to him 

 and to his comrades ; they fought for the greatest 

 achievement in the world's historv. R. •^• 



THE TREASURERSHIP OF THE ROYAL 

 SOCIETY. 



IN the list of the proposed Council of the Royal Society 

 for the ensuing year will be noticed a change in the 

 Treasurership. Sir John Evans, K.C.U., retires, and the 

 Council proposes to replace him by .Mr. Kempe. Con- 

 cerning this proposal the following letter has appeared 

 in the Times : — 



Sir,— The list of ofticers of the Royal Society proposed for 

 election at the general meeting at the end of this month, pub- 

 lished in the Times of Friday last, will not surprise any Fellow 

 who is acijiiainted with the inner history of the society during 

 the past lew years, but in the change of pcriounel of the 

 treasurership suggested it will astonish the great body of 

 Fellows and may well arouse misgiving, if not anxiety, in the 

 mind of the public— misgiving not to be lessened by the veiled 

 (viitmtiiiu/ia, intended, apparently, to allay apprehension, which 

 appeared in a certain section of the London jjress on Saturday. 

 The treasurer of the society is, like the two secretaries, a 

 permanent officer, and these three ofticers have, therefore, a 

 dominant influence in the atfairs of the society, the treasurer 

 having place by custom, at any rate next to the president. 



Oulside the society, too, in those responsible relationships 

 with the public which the position of the society, as represent- 

 ative of science, engenders these permanent oJticials have a voice, 

 consultative or execulive, for the society. The choice, then, of 

 treasurer is a matter of immediate moment to a wider circle than 

 the Fellows of the society, and the nomination to the office by 

 the present ofticers and council may therefore be fairly submitted 

 for criticism in the Timts. It is an open secret that an 

 influcnlial jirotest failed to arrest it. 



.Assuredly the roll of the society furnishes in abundance 

 names of Fellows well tried in its work and veter.ans in the 

 cause of science from which, as heretofore, a selection of 

 treasurer could be made which would not only safeguard the 

 inierests of the society but also be a guarantee to the public 

 that the best blood of ihe society was being devoted to the 



