622 



NA TURE 



[April 25, 1895 



winter distribution. Thus cold, dry, and therefore heavy, air 

 was drawn from the northeast over the British Isles, not only 

 lowering the air temperature directly, but clearing the sky of 

 the usual winter cloud layer, and thus allowing free radiation 

 at night, with consequent low night temperatures in valleys 

 where the chilled air can accumulate and lie stagnant. Places 

 thus situated recorded temperatures below zeio Fahrenheit, the 

 lowest being — 17° at Braeraar, and - 11° at Drumlanrig. At 

 western sea-coast places the frost seldom lasted for more than 

 twenty-four hours without a break ; while at inland stations, 

 such as Kingussie and Braemar, the temperature never rose to 

 the freezing point for fifteen consecutive days in February. No 

 very low temperatures were recorded on Ben Nevis, the lowest 

 being 2° above zero. On February 18, 19, and 20 the tem- 

 perature on Ben Nevis averaged 18° higher than that at Fort 

 William, 44CO feet below it, showing that the summit was in 

 the down draught of the anticyclone then lying over Scotland ; 

 while at sea level the warmth and dryness of this upper current 

 was not felt. The cold extended all over Europe, including 

 the South of Spain and the Riviera, but scarcely touched North 

 Africa. Though snow fell in Tunis, Algeria was beyond the 

 cold area, the winds there being mostly westerly. To the north 

 Iceland was the only part of Europe outside the influence of 

 the north-east winds, and the winter there has been mild and 

 open. — Mr. A. G. Herberlson presented an interim report on 

 hygrometric work at Ben Nevis. He also gave an account of 

 the Meteorological Observatory at Montpellier, France, 

 describing many of the instiumcnts employed there, and also 

 pointing out ihe excellent results got from regular phenological 

 observations. — Mr. Mossraan gave some notes on " Auroras in 

 the Norih-east of Scotland 1773 to 1S94," mainly taken from 

 data at Gordon Castle (Banffshire) and Inverness. The average 

 number of auroras in this district for the 122 years is seven per 

 annum, bit the numbers vaiy from fifty ca.'^es in 1870 to none 

 at all in jixleen yeais of the lecoid. An intimate connection 

 was shown between sun-spots and auroras ; maximum sun-spot 

 periods being the time whtn auroras were frer|uent and 

 brilliant, » bile with the absence of sun-spots there were few or 

 Done. No aurota was observed in any year between May 23 

 and July 22, that is, wilhin four or five weeks of the summer 

 solstice; and ihe rest of the year shows two maxima, a primary 

 in October and a secondary in February. 



DuntiN. 



Royal Dublin Society, January 23.— Prof. J. Mallet Purser 

 in the chair. — Mr. G. H. Carpenter read a paper on a collection 

 of Lepidoptera from Lokoja, West Africa.— Prof. A. C. 

 Haddon and Mr. J. E. Duerden ilescribtd some species of 

 Actiniaria from Australia and other countries. Ten species, 

 most of them new to science, were described anatomically, and 

 their relationship to other members of the group discussed. — 

 Prof. Iladdon then gave a paper on a branched worm-tube. — 

 Mr. Duerden followed with some notes on Ihe Hydroida 

 and Polyzoa collected during the Royal Dublin Society's 

 Fishery Survey on the West Coast of Ireland. In this paper 

 the author describes two new species of Pcri^onimus, and 

 records the occurrence of Cainpanulitui paiticula, G. O. Sats, 

 for the first time for the British seas. — A voluminous mono- 

 graph of the marine and freshwater Oslracoda of Ihe North 

 Atlantic and of North-Western Europe (Sections ii.-iv. : Myo- 

 docopa, Cladocopa, and Platycopa) was presented (through 

 Prof. A. C. Haddonj by Dr. G. S. Brady and the Rev. A. M. 

 Norman. — At the meeting held February 20, Prof. Grenville 

 A. J. Cole in the chair, Ihe following papers were read : — 

 Dr. V. Ball, C.B., F. R.S., made a communication in which 

 he gave an historical account of the gold nuggtts found in the 

 county Wicklow.— Prof. W. J. Sollas, I-.R.S., read a paper 

 descriptive of the systems of Eskers in Ireland. Some beau 

 tiful photographs of nebula; and clusters of stars, taken at 

 Daramona, co. Westmealh, were afterwards exhibited by Mr. 

 ^V. E. Wilson.— At Ihe meeting of March 20, Prof. G. F. 

 Fitzgerald, F. R.S., in Ihe chair. Prof. Sollas read a paper 

 upon Ihe age of the earth. — Prof. James Lyon demons'rated 

 lome of Ihe errors that arise from Ihe imperfect alignment of 

 the slide lathe. If the lino joining the centres of a slide la he 

 ii not laiallel to the line of motion of Ihe saddle, Ihe paih of a 

 cutter fixed in a bar which is rotated between the centres is a 

 plane which is not perpendicular to the direction of motion. 

 Any piece of material being bolted lo saddle, and having a 

 hole bored in it by the cutter, would be traversed by a hole the 



NO. 1330, VOL. 51] 



shape of which would be the projection of the cutting circle 

 on a plane perpendicular to the line of motion of saddle — i.e. 

 an elliptic cylinder would be the result. In the second case, if 

 the poppet-head centre be higher than the fixed centre, and a 

 bar of material be turned between Ihe centres by means of a 

 tool placed in the saddle at a heit,ht above the bed about equal 

 to Ihe height of the ctntre point of the axis of bar above the 

 bed, the result will be a hyperboloid of revolution, since this 

 surface is generated by a straight line (the palh of the tool), 

 which is always at a fixed distance from a given axis, is not 

 parallel to it, and does not intersect it. 



Paris. 



Academy of Sciences, April 16. — M. Marey in the chair. 

 — Observations on argon, ils fluorescence spectrum, by M. 

 Berthelot. The fluorescence of argon, when charged with 

 benzene vapour and submitted to the action of the silent dis- 

 charge, is described at length. It is noted that, with the second 

 sample of gas supplied by Prof. Ramsay, and under the con- 

 ditions'of the experiment, the condensation lakingplace amounted 

 to only 6 to 10 per cent. The author cannot yet explain the 

 dift'erent behaviour of Ihe first sample as regards condensation. 

 The following approximate measurements have been made in 

 Ihe spectrum of the fluorescent light : A yellow line at A 579 

 corresponding lo Ihe 575 argon line and 578 of the .aurora 

 borealis ; a green line at X 547 corresponding wilh Crookes' 

 group 549 to 555, and perhaps with 557 of Ihe aurora; 

 violet lines 43S and 436 corresponding with Crookes' 433 

 and 430, and with an important aurora line. — A con- 

 tribution to Ihe study of variability and capacity of trans- 

 formation in microbiology, as illustrated by a new variety of 

 anthrax bacillus (Bacillus anthracis clai-iformis), by M. A. 

 Chauveau and M. C. Phisalix. The cultivation obtained from 

 the lymphatic ganglion of a guinea-pig inoculated with at- 

 tenuated anthrax bacilli consisted of a new type which retained 

 only in a very slight degree the immunising power of the 

 attenuated culture, and no longer had any toxic action beyond 

 that evidenced by a certain rise in temperature of Ihe inoculated 

 subject. The authors believe the Bacillus anthracis clavi- 

 forittis to have been certainly derived from virulent Bacillus 

 anthracis, but they have not as yet succeeded in bringing back 

 the new variety to the original virulent form. — On the minimum 

 temperatures observed this winter at the summit of Mont Blanc, 

 by M. J. Janssen. A description is given of the mounting of 

 the minimum thermometers. The following minima have been 

 recorded: Mont Brivent -26''C. ; Mont Buet -33''C. ; Mont 

 Blanc -43"C. — Secular variation and ephemerides of terrestrial 

 magnetism, by General Alexis de Tillo. — Researches on 

 assimilable nitrogen and ils transformations in arable Land, by 

 M. Pagnoul. The conclusions are drawn that : (l) Abundant 

 rains may carry off from rich soils considerable amounts of 

 nitric nitrogen. (2) Plants growing on the soil are able to 

 prevent this loss. (3) Carbon disulphide arrests the action of 

 the nitric fetinent temporarily without killing it. (4) The 

 ammoniacal form is a transition state for organic nitrogen pass- 

 ing into the nitric form ; carbon disulphide causes Ihe temporary 

 suspension of Ihe .action at this stage. (5) The nitrous form is 

 also an unstable transition slate. — On the products of combustion 

 in the electric arc, by M. N. Grchanl. Carbon monoxide is 

 produced and, in confined spaces, has produced illness among 

 the workmen employed in electric light stations. — On a question 

 concerning the singular points of algebraical left-handed curves, 

 by M. G. B. Guccia. — Summation of series by means of 

 definite integrals, by M. Petrovitch. On types of groups of 

 subslitutions of which the order equals the degree, by 

 M. R. Levavasseur. — On the theory of the system of 

 differential equations, by M. A. J. Slodolkievitz. — 

 On Rondelei's rule for woods, and beams loaded 

 on end, by M. C. Mallczos. Rondelei's rule is reduced for 

 wood lo a parabolic formula. The curve of limit loads for 

 wood, lion, and brass, between wide limits for Ihe ratio of 

 length of beam to smallest side of transverse section, may be 

 replaced by an arc of a single parabola. — Electric discharge by 

 illumination of substances which are mediocre conductors, by 

 M. Edouard Braiily.— On a new method for Ihe measurement 

 of Itmperalutes, by M. Daniel Beilliclot. The author pro- 

 p OSes the ddeimination of density of gases, by means of their 

 rcfraclive indices as investigated by interference fringes, as a 

 basis for measurement of temperature by a property of gases 

 independent of Ihe envelope. — On the presence of helium in 



