May 26, 1898] 



NATURE 



95 



harmless, monobromonaphthaline and phenylthiocarbimide were 

 not likely to injure even delicate tissues, but he thought the 

 mixture of metacinnamene and phenylthiocarbimide approached 

 most nearly to balsam in permanency and neutrality. Dr. 

 Dallinger said he had specimens mounted in nearly every 

 medium which had been mentioned, but at the present time 

 only one of these slides was in good condition ; nevertheless, it 

 was most important that such media should be available. The 

 President referred to a table of coefficients which he had worked 

 out to show the comparison of the refractive indices and dis- 

 persive powers of these new media with those of some well- 

 known glasses. — Mr. Morland exhibited about three dozen slides 

 of diatoms. — Mr. J- J- Vezey read a short note by Mr. E. B. 

 Stringer, supplementary to his paper on photomicrography 

 which was read at the meeting of the Society in December last. 



Mathematical Society, May 12.— Prof. Elliott, F.R.S., 

 President, in the chair. — Mr. A. E. H. Love, F.R.S., gave an 

 account of some fundamental properties of manifolds. — Lieut. - 

 Colonel Cunningham, R.E., communicated a description of " the 

 77 squares puzzle," hy Major Turton, R.E., and exhibited a 

 cardboard specimen of the puzzle. He also reported that the 

 complete factorisation of the numbers N = 3" -f- 1 , where « = 61' + 3, 

 had now been effected by the joint work of Mr. C. E. Bick- 

 more and himself for the following values of « (51, 57, 69, 

 75. 81, 93 in part, 99, 105), thus completing the factorisation 

 of these numbers up to «=io5 (except 93 in part), those 

 from « = 3 to 45, 63, 87 being previously known. These 

 numbers include several high primes of 9, 10, 11 figures. 

 — The President communicated a paper, by Mr. H. G. Dawson, 



/"A o 



on the numerical values of / e'' dx ; and one by Prof. H. 



/h < 



Lamb, F. R.S. , on the reflection and transmission of electric 

 waves by a metallic grating. Impromptu remarks were made by 

 the President (in connection with the figure of Pascal's theorem) 

 and by Mr. F. S. Macaulay. 



Zoological Society, May 17.— W. T. Blanford, F.R.S., 

 Vice-President, in the chair. — Mr. Oldfield Thomas read a 

 paper on a small collection of Mammals from Nyasaland that 

 had been presented to the British Museum by Mr. Alfred 

 Sharpe, C.B. Sixteen species were enumerated, mostly from 

 North Nyasaland. Among them was a new antelope from 

 Urori, coloured like Cephalophtis ceqiiatorialts, but with horns in 

 the female, as in C. monticola. — A communication was read 

 from Dr. A. G. Butler on a collection of Lepidoptera lately 

 made in British East Africa by Mr. C. S. Betton. It contained 

 examples of 123 species of butterflies and of iil species of 

 moths. Among the moths were forms which were referred to 

 five new genera, viz. Bettonia, Aclonophlebia, Trotonotus, 

 Hanieopis, Lembopteris, and Metaculasta. Besides these new 

 genera thirty new species were characterised in this paper. — 

 Mr. F. 6. Beddard, F.R.S., communicated a paper by Miss 

 Sophie M. Fedarb on some earthworms from India. Four 

 species were treated of in this paper, of which the following 

 three were described as new : — Perichata ciipulifera, P. 

 crescentica, and Dichogaster parvus. — Mr. W. E. de Winton 

 described a new rodent of the family Anomaluridte from the 

 Benito River, French Congo, which was referred to a new genus 

 Aethiirus, differing from both Anomahiriis and Idiurtis in not 

 having any expanded flying-membranes, but resembling the 

 former in the formation of the tail, and being more like the 

 latter in the form of the skull. The species, proposed to be 

 named Aethurus glirinus was of the same size as Anomalurus 

 iatesi, grey in colour, with a black bushy tail and a thickening 

 of the skin of the lower leg, in which are set jet-black, club- 

 shaped hairs forming anklets. — A communication was read 

 from Mr. Stanley S. Flower, in which he pointed out that the 

 gecko from Penang described by Stoliczka as Cyrtodactylus 

 affinis and that described by himself under the name of 

 Gonatodes penangetisis were identical, and that the proper appel- 

 lation of the species would be Gonatodes affinis. 



Royal Meteorological Society, May 19.— F. C. Bayard, 

 President, in the chair.— Mr. R. H. Scott, F.R.S., read 

 a. paper on the frequency of rainy days in the British Islands. 

 He had taken the number of rainy days in each month at forty 

 stations for the twenty years 1876-95, and then divided that 

 number by the total number of days in the month, and so ascer- 

 tained the resulting percentage. The greatest excess of frequency 

 is always on the extreme north and west coasts. June is the 



NO. 1 49 I, VOL. 58] 



month with the least number of rainy days, but in July the sum- 

 mer maximum of rain occurs, bringing the well-known Lammas 

 floods. In October the weather becomes decidedly showery, 

 and the distribution begins to assume its winter type. November 

 is the month with the greatest frequency of rainy days. — Mr. F. 

 J. Brodie read a paper on the abnormal weather of January last, 

 which was one of the most remarkable winter months on record. 

 The month was singularly dry, with an absence of snow or sleet — 

 a somewhat unusual feature in January even for any individual 

 station, but far more remarkable as applying to the country as a 

 whole. The special feature, however, was the striking absence 

 of severe frost, the frequent prevalence of unusually mild weather, 

 and as a result the abnormal warmth of the month, especially in 

 the more northern parts of the kingdom. The mean temperature 

 was generally over the whole country about 5° above the average, 

 while at many places situated in the more northern parts of the 

 kingdom it was more than 6° above the average. The atmo- 

 spheric pressure throughout the month was also very high, the 

 mean being from two to three tenths of an inch above the 

 average. 



Cambridge. 

 Philosophical Society, May 2. — Mr. F. Darwin, President, 

 in the chair. — On the theory of order, by Mr. E. T. Dixon. All 

 the theorems of non-metrical (projective) geometry depend 

 solely on the conception of "order" so defined as to be in- 

 dependent of the idea of " before or after," which belongs only 

 to time. It follows from this definition that no "order" can 

 be ascribed to less than four units in any uniform group : and 

 this is why less than four points have no " projective relation" 

 or an harmonic ratio. The paper further discusses the way in 

 which numbers (or coordinates) may be assigned to the units of 

 a group for purposes of analysis, with or without a system of 

 "unique" lines having already been determined. — On the 

 representation of a function, by Mr. tl. F. Baker. — On the total 

 eclipse of the sun, January 22, 1898. by Mr. H. F. Newall. A 

 general account was given of the observations made during the 

 recent eclipse, and photographs were exhibited, showing: (i) 

 the general appearance of the corona ; (2) the spectrum of the 

 sun's limb as photographed with prismatic cameras by Sir 

 Norman Lockyer's party, and by Mr. Evershed ; (3) the spec- 

 trum of the sun's limb as photographed with a slit spectroscope. 

 —Captain E. H. Hills, R.E., exhibited and described the photo- 

 graphs obtained by him of the spectrum of the corona, and also 

 the two series of photographs of the spectrum of the sun's limb 

 at the beginning and end of totality. 



Paris. 

 Academy of Sciences, May 16. — M. Wolf in the chair. — 

 The Secretary announced to the Academy the loss it had sus- 

 tained by the death of M. Souillart, Correspondant in the Section 

 of Astronomy. — On the impossibility of certain series of groups 

 of points on an algebraic surface, by M. 6mile Picard. — On some 

 causes of uncertainty in the exact estimation of carbonic acid 

 and of water vapour, diluted with large volumes of air or inert 

 gases, by M. Armand Gautier. It is shown that potash, even 

 when spread over long columns of glass beads, is incapable of 

 removing the last traces of carbon dioxide from air. This, 

 however, is readily accomplished by the use of a U-tube con- 

 taining moistened baryta. The increase of weight of a phosphoric 

 anhydride tube after passing through it large volumes of air dried 

 over sulphuric acid was also determined, the amount being of the 

 order of 0'4 mgr. for loo litres of air. An attempt was made to 

 estimate the maximum amount of sulphuric acid vapour carried 

 away by 100 litres of air, and the conclusion drawn that 

 at ordinary temperatures the vapour pressure of sulphuric 

 acid in air must be less than one twenty-millionth. — On an 

 absolute actinometer, by M. A. Crova. The instrument de- 

 scribed is a modification of those proposed by M. Knut- Angstrom 

 and M. Chwolson, consisting of a thin disc of pure copper, 

 suitably protected from accidental radiations, and placed nor- 

 mally to the sun's rays, the temperature being measured by the 

 resistance of a thin constantin wire. — Agglutination of the 

 bacillus of true tuberculosis, by M. S. Arloing. Certain serums 

 have the power of causing the bacilli of true human tuberculosis 

 to cohere. An attempt will be made to see whether this 

 property can be applied to the diagnosis of tuberculosis in man, 

 analogous to the method now used for typhoid fever. — On the 

 development of the disturbance function, by M. Adrien Feraud. 

 — On the quadratic and rational correspondence of two plane 

 figures, and on a remarkable substitution, by M. Ernest 



