Isotherms of methane have been determined for a series of temperatures between 0º and 200º C. by Keyes, Smith, and Joubert, and by Keyes and Burks, but, inasmuch as the highest pressure reached at 0º in these researches was 130 atmospheres, and the isotherm as extrapolated from their derived equation did not indicate the expected pv A minimum at about 150 atmospheres ( vide 3), it was deemed advisable to extend the measurements at 0º to 220 atmospheres, and also to determine the isotherm at 20º C. Olszewski was the first to measure the vapour pressures of methane, down to a temperature of –203º C., but his results are chiefly of historical interest. Determinations of the vapour pressures of the liquid between –182º and –150º C. have been made by Stock, Henning, and Kuss, but, apart from a solitary measurement of the triple-point by Crommelin, no modern work seems to have been done on the vapour pressures of the solid. The range between –178º and the critical temperature has been covered by Keyes, Taylor, and Smith in a comprehensive paper upon the thermodynamic properties of methane.

The study of the equilibria described herewith was undertaken primarily for the purpose of discovering the best method of preparing ammonium perchlorate from sodium perchlorate. The equilibrium itself, is, however, of interest from the purely theoretical point of view.The sodium and ammonium sulphates used were made by the recrystallization of the ordinary laboratory supply of these materials. A large supply of very pure ammonium perchlorate was available, and sodium perchlorate was made by the action of pure caustic soda on this salt in aqueous solution.Gas heated thermostats of the ordinary pattern were used. The thermometers were checked against standardized instruments from the National Physical Laboratory.The bottles in which the solubility determinations were carried out were similar in pattern to those described by van 't Hoff ').Samples of the clear solutions were taken in a weight pipette. The composition of the solid phases was determined by the residue method of Schreinemakers z), the geometrical method described by the same author3) being used for the four component system. Ammonia was determined by distillation with excess of NaOH, the ammonia being absorbed in excess standard acidand the excess titrated back. Na was determined by taking down with pure sulphuric acid in silica basins at a low red heat. SO, was determined by the ordinary BaSO, method.ClO, was usually determined by difference, but very special care was taken to work with such quantities of material as were most suitable to give the most accurate results : transference was avoided as far as possible, and ali analyses were done in duplicate.Graphical representation in a quaternary system in space and in a plane. W e will now briefly consider the form of representationThe materials used.

This biography of Arthur John Allmand is compiled from the personal record he left with the Society, from appreciations of pupils and friends, and from the recollections of the author who worked side by side with him in Liverpool and maintained a life-long friendship with him. The plan of the biography is first to take the reader through the answers to the Society’s questions followed by an appreciation of his work and character. Allmand’s favourite dictum on a professor of one of the natural sciences was that he might be a great researcher, a great administrator or a great teacher. Sometimes he might shine in two of these categories but to do so in all three was unattainable for most people. This should be borne in mind, as it was undoubtedly the pattern to which his life conformed. Allmand’s father, Frank Allmand, was a flour miller of Wrexham, a quiet pale man like his son, who attained the great age of ninety years. His mother’s maiden name was Thomas and her father was a timber merchant of Wrexham.

His life T his biography is compiled from the Personal Record which Donnan left with the Royal Society, the assistance of numerous pupils and friends, and from the recollections of the writer extending over a long period. D onnan was bom on 5 September 1870 at Colombo, Ceylon, and was the second of a family consisting of two brothers and four sisters. His father was William Donnan, a merchant of Belfast, and his mother's maiden name was Jane Ross Tumley Liggate she also being a native of Northern Ireland. Donnan's uncle, Captain James Donnan, was 'master attendant', Colombo and Inspector of the Ceylon Pearl Fisheries, who received a C.M.G. on his retirement; his son, Donnan's cousin, was a regular soldier who spent most of his life in India, retiring with the rank of Colonel in 1913, rejoining the Army in 1914, and dying of heat stroke in Mesopotamia. Donnan's brother, William Dunlop Donnan, was a general medical practitioner (M.D. of the Queens University) of Belfast till his death in 1941. Donnan returning from Ceylon at the age of 3 had no recollections of that country at all and this must be considered in making any appreciation of him as a devoted Ulster patriot. Donnan was a bachelor, so particular and generous mention must be made of his two sisters Jane and Leonora (Nora) who played such an impor tant and unobtrusive part in his life. Jane was his secretary at University College and later looked after the I.C.I. Research Associates working there; after his retirement she carried on with his correspondence. In these later years her eyesight began to fail and steadily worsened. She died only three days before her brother and they were cremated on the same day. On duty she was most intelligent and efficient and in private life had all the family charm. Leonora (Nora) kept house for Donnan for about 38 years, dying in May 1956. Donnan's father who spent most of his working life in the firm of Brown Corbett & Co. of Belfast, was in his earlier years in the firm of Shand Brothers, Ceylon. Donnan lived with his parents near Bangor, County Down, from 1875 to 1879, and in Holywood in the same County from 1884 to 1893, in the inter vening period they lived in Belfast. In the year 1879 he lost his left eye. I knew Donnan intimately for more 24.

James Swinburne lived to be over one hundred years of age, the third Fellow of the Royal Society to do this. The first was Sir Moses Haim Montefiore who was born in Leghorn on 24 October 1784 and died in this country on 28 July 1885, having settled here as a young man. He was elected into the Society on 16 June 1836. He is still well remembered as an outstanding philanthropist and a fearless defender of his fellow Jews all over the world. The second was Henry Nicholas Ridley the botanist who died in 1956. One other Fellow who died a few days before his hundredth birthday might well be mentioned; he was Bernard le Bovier de Fontenelle, Secretary of the Académie des Sciences and later President of that body. Fie was born on 11 February 1657 and died on 9 January 1757. Family, Early Life and Background The Swinburne family is an ancient one as a glance at Burke's Peerage will show; they are essentially Northumbrian. The baronetcy dates from 1660. John Swinburne, father of the first Baronet, was promised a baronetcy by Charles I but the patent of creation never passed the seal. He died in 1652, eight years before the Restoration, His son, also John Swinburne, was created a Baronet in 1660 and is called in the patent ‘Virum patrimonio censu et morum probitate spectabilem’. Swinburne on his father’s side was descended from Flotspur, of whom he dryly remarks in his personal record ‘was a lively member of society but not noticeably scientific’. One of Swinburne’s ancestors (Sir John Swinburne, Bart.) was a Fellow of the Society elected 26 February 1818. Like so many of his contemporaries of the period he was an ardent antiquarian and F.S.A. Humphry Davy was his proposer for the Society. He founded the Antiquarian Society of Newcastle upon Tyne, closely modelled on the L.S.A., and during his lifetime maintained the most friendly intercourse between the two Societies. He, like our Swinburne, lived to a great age, dying a few weeks short of his entry into his hundredth year.