June 28, 1906J 



NA TURE 



215 



Physical Society, June 8.— Prof. J. Perry, F.R.S., 

 prcsiiiciif, in the chair. — The solution of problems in 

 clirfr.ii lion by the aid of contour integration ; 11. Davies. 

 Thi- method adopted is to obtain a solution for unbounded 

 space as a contour integral. The special boundary con- 

 ditions are then accounted for by adding terms to the 

 previous e.Kpression. When the complete expression has 

 been obtained it is then evaluated in the form of a series 

 by till- aid of Cauchy's residue theorem. — J. Goold's ex- 

 periments with a vibrating steel plate : Newton and Co. 

 The phenomena peculiar to this plate may be classified 

 under two heads : — (i) beats, simultaneously audible and 

 visible; (2) dispersion figures. In addition to these, vortex- 

 vibration, resonance-effects, and many other experiments 

 may be exhibited by using suitable clamps, &c. The dis- 

 persion figures are due chiefly to the interaction of two 

 systems of vibrations of the same pitch working at right 

 angles to each other. — Fluid resistance : Colonel R. 

 de Villamil. Prof. Hele-Shaw, in a paper on the motion 

 of a perfect fluid, remarks that one of the most perplexing 

 tilings in engineering science is the absence of all apparent 

 conn'Htion between the higher treatises on hydrodynamics 

 and the vast array of works on practical hydraulics. The 

 reason for this appears to be the immense difference 

 between the flow of an actual liquid and that of a perfect 

 one, owing to the property of viscosity. According to the 

 author, this is not the only reason. There appear to be 

 two fundamental difficulties to be got rid of before they 

 can be reconciled. Engineers assume that a liquid can be 

 " pushed " in any rectilinear direction. This, though a 

 very popular notion, is not correct. The other difficulty is 

 the assumption that in a perfect fluid there can be no 

 resistance of any kind to any body moving in it at any 

 velocity. It is only in an infinite ocean of perfect fluid 

 that there would be no resistance. 



Society of Chemical Industry (London Section), June 11. 

 — Mr. .A. G. Salamon in the chair. — Purifying and stabil- 

 ising guncotton : Dr. R. Robertson. This communication 

 — published by permission of the War Office — deals with 

 large-scale experiments having for their object the best 

 means of obtaining a pure and stable guncotton by a 

 boiling process. For the elimination of impurities from 

 the guncotton and the rapid attainment of a stable pro- 

 duct, boiling in dilute acid at the beginning of the process 

 is superior to an alkaline treatment, which has the 

 additional disadvantage of tending towards an undue 

 hydrolysis of the ester itself. The acid hydrolysis must 

 not be unduly curtailed, or elimination of the impurities 

 will be rendered difficult. — The determination of indigotin 

 in commercial indigo and in indigo-vielding plants : C. 

 Bergtheil and R. \'. Briggrs. The authors have investi- 

 gated the standard methods of estimating indigotin in 

 commercial ' " " , ■ It is shown that all the methods dealt 

 with are trustworthy when applied to pure indigotin, but 

 that in application to commercial indigo the impurities 

 present lead to errors ; only those methods depending on 

 the oxidation or reduction of solutions of sulphonated 

 indigo are found to be applicable in this case. — Recent 

 progress in the cement industry : B. Blount. The author 

 compares the condition of the cement industry in 1886 

 and at the present time, pointing out that at the former 

 date somewhat crude methods of manufacture were in 

 use, whereas now improved processes are in operation 

 under scientific control. The world's production of Port- 

 land cement has increased from 2,500,000 tons to some 

 11,000,000 tons in the last twenty years, and the centre 

 of the industry has shifted from Europe to the United 

 States. The second part of the paper deals with improve- 

 ments in controlling the quality of cement in the works 

 and by the user which have been made during the last 

 twenty years. 



Royal Meteorological Society. June 20. — Mr. Richard 

 Bentley, president, in the chair. — The mean prevalence of 

 thunderstorms in various parts of the British Islands during 

 the twenty-five years 1881-1905 : F. J. Brodie. The 

 author gives the mean number of days on which thunder- 

 storms, or thunder only, occurred in each month, each 

 season, and in each year at fifty-three stations situated 



NO. IQI3. VOL 74I 



in various parts of the United Kingdom. July is the month 

 with the largest number of thunderstorms over Great 

 Britain as a whole, and August at some places in the 

 north of Scotland and north-west of England, while June 

 is the stormiest month at nearly all the Irish stations. 

 For the whole year the largest number of thunderstorms 

 is over the northern and eastern parts of England, where 

 more than fifteen occur, while there are less than five 

 in the west and south of Ireland and at most places in 

 the north of Scotland. The sumitier distribution of thunder- 

 storms is very similar to the annual distribution, while 

 the winter distribution is quite different, when the largest 

 numbers occur along the west coasts of Ireland and Scot- 

 land and extreme south-west of England. — Typical squall 

 at Oxshott, May 25, 1906 : W. H. Dines. During the 

 morning there was a steady wind from the south-west of 

 more than ten miles per hour until 11 a.m., when there 

 was some falling off for fifteen minutes, then a rise to 

 more than twenty miles per hour, accompanied by a sudden 

 increase of barometric pressure and a fall of a few 

 hundredths of an inch of rain. After the squall the wind 

 dropped suddenly, and there was almost a dead calm for 

 about twenty minutes. The author, who was flying a kite 

 at the time, gave some account of the changes in the wind 

 at a considerable altitude above the earth. At 11.26 a.m. 

 the squall struck the kite, which was then at a height of 

 2400 feet. Two minutes later the velocity at the kite 

 had risen to fifty-eight miles per hour, and the wire broke 

 under a strain of 180 lb. Three minutes later the kite 

 fell at a spot 2J miles distant from Oxshott. 



Edinburgh. 

 Royal Society, Tune 4. —Dr. R. M Traquair, F.R.S., vice- 

 president, in the chair. — Recherches sur la Glauconie : Drs. 

 L^on W. Collet and Gabriel W. Lee. The paper contained 

 a careful examination of the chemical composition of the 

 mineral glauconite, which was found in what Sir John 

 Murray called, in the Challenger expedition reports, the 

 blue and green muds of the ocean beds. It was shown that 

 glauconite was ferric silicate, and not ferrous silicate, as 

 had been stated by Calderon and Chaves, of Madrid. — A 

 rare dolphin, Delphinus acutus, recently stranded on the 

 coast of Sutherland : Sir William Turner, K.C.B. There 

 were very few previous records of this species having been 

 found in the vicinity of the Scottish shores. — Contributions 

 to the craniology of the people of the Empire of India, 

 part iii., natives of the Madras Presidency, Thugs, Veddahs, 

 Tibetans, and Seistanis : Sir William Turner, K.C.B. 

 Among the skulls exhibited were those of some of the 

 famous Thugs who practised highway murder with such 

 skill and secrecy as to elude for long the authorities in India. 

 Their crimes were regarded by themselves as a religious 

 duty. The skulls were all well formed, with no resemblance 

 to what some have called a criminal type. Of the two 

 Tibetan skulls, one was of Mongolian type, but the other 

 was that of a Kham warrior from eastern Tibet, and its 

 dolichocephalic form supported Grierson's theory of the 

 Tibeto-Burman stock. The three skulls from Seistan, in 

 south-west Afghanistan, belonged to two types, one 

 approximating to the .Afghan and the other to the 

 Beluchistan type. — Interpolation for a table of fractions, 

 with a notice of synthetic division and its use : Dr. James 

 Burgress, CLE. All fractions with denominators under 100 

 and numerators less than 50 were tabulated in order of 

 magnitude. The formulae q = nld = (n-i-q)/{d+t) suggested 

 a simple and rapid way of dividing by any number differing 

 by unity from a simple multiple of 10, 100, 1000, &c. — 

 The length of the normal chord of a conic ; Prof. Anglin. 

 — The hydroids of the Scottish National Antarctic Expedi- 

 tion : James Ritchie. The collection brought home by 

 the Scotia was very large. There were forty-five speci- 

 mens giving one new genus, nine new species, and several 

 new varieties. The new genus had been named Brucella, 

 in honour of Mr. W. S. Bruce. The Scotia collection also 

 extended our knowledge of the geographical range of 

 hydroids. especially towards the .Antarctic regions. — Prof. 

 D. J. Cunninghant exhibited a photograph taken from a 

 bridge of a large number of salmon resting in the Corrib 

 River, Galway. 



