ASSOCIATION'S FoR A DVANCKMF.N'T OF SCIEXCE. (P,Krnsii.j 



41 



Among tin.- more important paper- pre-eiited be- 

 fore the section were: "The Evolution of Stellar 

 :ns." liy Isaac Robert:-: " UH Periodic Orbits." 

 by (ie..rge 11. Darwin: Researches on Cathode 

 Rays." by P. Leonard: "The Laws of Conduction 

 of Electricity through Gases exposed t< the Ront- 

 gen Kays." by Joseph J. Thomson and E. Ruther- 

 ford ; " The Transparency of Glass and Porcelain to 

 the Rontgen Kays," by Arthur \V. Riicker and W. 

 - 'ii : "On Measurements of Electric Currents 

 in Air at Different Densities," by Lord Kelvin. James 

 T. Bottomley. and Magnus Maclean : " On the Dura- 

 tion of the X-Radiation at Each Spark." by F. T. 

 Troutoii : " On the Relation between Cathode Kays 

 and X-Kays and Becquerel's Kays." by Sylvanus P. 

 Thompson: "On the Plotting out of Great Circles 

 on a Chart. "by II. M. Taylor: " Experiments of M. 

 Birkeland on the Cathode Rays." by V. Bjerknes : 

 "On Hyperphorescence." by S. J'. Thompson: 

 "Some observations on the X-Kays," by II. II. F. 

 Ilaysman: " On the Component Fields of the Earth's 

 Magnetism." by Louis A. Bauer: "A One- Volt 

 Standard Cell with Small Temperature Coefficient." 

 by W. Hibbert ; "Keostine: A Xew Resistance Met- 

 al." by J. A. Harker : The Communication of Elec- 

 tricity from Electrified Steam to Air." by Lord Kel- 

 vin and Magnus Maclean: "On the Molecular Dy- 

 namics of Hydrogen Gas, Oxygen Gas. Ozone, Hy- 

 drogen Peroxide. Vapor of Water, Water. Ice. aiid 

 Quartz Crystals." by Lord Kelvin: "A Method of 

 detecting Electro-magnetic Waves.'' by E. Ruth- 

 erford : " The Effect of Refraction on "the Diurnal 

 Movement of Stars and a Method of allowing for it 

 in Astronomical Photography." by A. A. Rambaut; 

 "On the Sailing Flight of B'irds." by (i. II. Bryan : 

 "The Stanhope Arithmetical Machine of 1780."" by 

 Robert Harley : " Exploration of the L'pper Air by 

 Means of Kites," by A. Lawrence Rotch ; " Some 

 Experiments on the Diffusion of Electrolytes," by 

 W. C. I). Wherham: "The Total Heat of" Water." 

 by William X. Shaw: "An Apparatus for the 

 Measurement of Electrical Resistance." by E. II. 

 Griffiths ; " Researches in Absolute Mercurial Ther- 

 mometry." by S. A. Sworn; "On the Division of an 

 Alternating Current in Parallel Circuits with Mu- 

 tual Induction." by Frederick Bedell, of Cornell 

 University, Ithaca. X. Y. ; "Carbon Megohms for 

 High Voltages," by W. M. Mordley : " Measurements 

 of the Velocity of" Rotation of the Planets by the 

 Spectroscopic Methods." by James E. Keele'r, of 

 Alleghany Observatory, Pa! : " The Photo-electric 

 Sensitization of Salts by Cathode Rays." by J. 

 Elster and II. Geitel : " On Change of Absorption 

 accompanying Fluorescence." by John Burke: " Ho- 

 mogeneous Structures and the Symmetrical Parti- 

 tioning of them." by William II. Barlow : and "On 

 Electrical Disturbances in Submarine Cables." by 

 William II. Preece. 



Also the following reports were presented : " On 

 the Establishment of a National Physical Labora- 

 tory," by Sir Douglas Galton : -On Magnetic Stand- 

 ards," by Arthur W. Riicker : "On the Comparison 

 and Reduction of Magnetic Observations," by W. 

 Ellis: "On Electrolysis." by William X*. Shaw; 

 "On Electrical Standards." by Richard T. Glaze- 

 brook : and " < )n Meteorological Observations on Ben 

 Nevis,* "On Solar Radiation." "On Srismological 

 Observations." - ( }n Meteorological Photographs," 

 and " ( h\ the Sizes and Pages of Periodic 



B. Che>/' ice, The opening address be- 

 fore this section was by Dr. Ludwig Mond. F. K. >.. 

 ^& past president of the Society of Chemical Indus- 

 try and a member of the firm of Brunner. Mond 

 & Co., the great chemical manufacturers of Chesh- 

 ire. The subject of his address was the "History 

 of the Manufacture of Chlorine." Dr. Mond began 

 with the Arabian alchemist Geber, and traced the 



history of chlorine in a/ji/ti rri/ia until 1774. when 

 the Swedi.-h chemist Scheele separated it from 

 aqua n-'/iti as a gas that could not be decomposed, 

 and called it dephlogisticated muriatic acid. The 

 researches of Lavoisier. Berthollet. and others were 

 discussed, and especially Berthollet's application of 

 its color-destroying properties to bleaching. Dr. 

 Mond then followed with a description of the early 

 work of Charles Tennant in its manufacture, and 

 quoted from Higgins. who. in 1799. described "the 

 means of bleaching with the oxygenated muriatic 

 acid and the methods of preparing it." Davy's re- 

 iies were considered in detail, and Dr. Mond 

 then took up the various methods used in the manu- 

 facture of chlorine at the works at St. Rollox since 

 1845. Weldon's process, patented in 1866. was then 

 considered, after which the Solvay process and the 

 Deacon process were described, both of which, the 

 speaker said, were shown in actual operation at the 

 last meeting of the association that was held in 

 Liverpool. The Deacon process has supplanted the 

 Weldon process in nearly all the largest chlorine 

 works in France and Germany, and is now making 

 very rapid progress in England. 



The later processes, notably that of Pechiney in 

 France and that of Pick in Austria, were described, 

 and finally he gave an account of the electrolytic 

 process invented by Hamilton Y. Castner, of New 

 York, whose process has been at work for some time 

 in Oldbury. near Birmingham, and works for carry- 

 ing it out on a large scale are being erected on the 

 banks of .the Mersey, and also in Germany and in 

 America. In conclusion, he said : " I can not leave 

 my subject without stating the remarkable fact that 

 every one of these processes which I have described 

 to you is still at work to this day, even those of 

 Scheele and Berthollet, all finding a sphere of use- 

 fulness under the widely varying conditions under 

 which the manufacture of chlorine is carried on in 

 different parts of the world." 



Among the more important papers presented be- 

 fore this section were : " On Reflected Waves in the 

 Explosion of Gases," by Harold B. Dixon ; " The Ac- 

 tion of Metals and their Salts on the Ordinary and 

 Rontgen Rays a Contrast," by Dr. John H. Glad- 

 stone and Dr. W. Hibbert; "On the Limiting Ex- 

 plosive Proportions of Acetylene and the Detection 

 and Measurement of the Gas in the Air " and " On 

 the Accurate Determination of Oxygen by Absorp- 

 tion with Alkaline Pyrogallol Solution." by Frank 

 Clowes : " Amides of the Alkaline Metals and some 

 of their Derivatives." by A. W. Titherly : " Nitrates : 

 Their Occurrence and Manufacture." by William 

 Newton: "On Helium," by William Ramsey ; "The 

 Discovery of Argon in the Gas of an Australian 

 Well." by Prof. Bamberger; "The Processes pro- 

 posed for the Manufacture of Chlorine by Means of 

 Nitric Acid." by F. Hurter : " Chemical Results 

 obtained at exceedingly Low Temperature." by 

 James Dewar: "Two New Forms of Apparatus." 

 by C. A. Kohn ; "Detection and Estimation of Car- 

 bon Monoxide in the Air." by Dr. Haldane: "The 

 Detection and Estimation of Carbon Monoxide by 

 the Flame-Cap Method." by Frank Clowes : "Chem- 

 ical Education in Germany and England." by Sir 

 Henry K. : The Teaching of Science in 



Girls' Schools." by Miss L. Edna Walter. 



A series of interesting philosophical experiments, 

 with a view of proving the diminution of chemical 

 action resulting from limitations of space, were 

 presented by Prof. Liebrich. of Berlin. Also the 

 following reports were presented : " On the Con- 

 stituents of Barley Straw." by C. F. Cross : < )u the 

 Constituents of Coal." by Prof. Bedson : " On Quan- 

 titative Methods of Electrolyses." by Dr. C. A. 

 Kohn : and " On the Teaching of Science in Ele- 

 mentary Schools," by John H. Gladstone. 



