John Hall Gladstone. 189 



towards natural science, and in 1844 he elected to take up science as 

 a calling, and went to University College to attend the chemical 

 lectures of Graham, and to work in his private laboratory. Whilst 

 here he gained a Gold Medal for original research, and published his 

 first contribution to scientific literature in the form of a paper on 

 Guncotton and Xyloidine. In 1847 he went to Giessen University to 

 work under Liebig ; here he took his degree as Doctor of Philosophy, 

 and returned to London in the following year. In 1850 he was 

 appointed Lecturer in Chemistry at St. Thomas's Hospital, and in 

 1853, at the age of 26, he was elected into the Royal Society. Six 

 years later he was made a Member of the Eoyal Commission on 

 Lighthouses, Buoys, and Beacons, and from 1864 to 1868 he served as 

 a Member of the Guncotton Committee, appointed by the War Office. 

 He held the Fullerian Professorship of Chemistry at the Royal Insti- 

 tution from 1874 to 1877, and was President of the Physical Society, 

 of which he was one of the original founders, in the year of its 

 formation in 1874, and was President of the Chemical Society, of 

 which he had been a Member since 1848, in 1877 79. He was one of 

 the six past Presidents of the last-named Society who could boast of a 

 membership of over fifty years, and in whose honour a banquet was 

 given in 1898. 



As a man of science, Dr. Gladstone will be mainly remembered for 

 his share in the early development of Physical Chemistry, and 

 especially of that portion of it which is concerned with the relations 

 of Chemistry to Optics. He was one of the earliest workers in 

 Spectroscopy and on the application of the prism to chemical analysis, 

 and he was the first to detect the remarkable optical behaviour of 

 didymium and its solutions. He published a series of papers on the 

 solar spectrum, one of them in conjunction with Sir David Brewster, 

 and on the spectra of gases. He worked also on fluorescence and 

 phosphorescence, on chromatic phenomena, and on circular polarisation ; 

 on the influence of temperature on the refraction of light, and on the 

 refraction equivalents of the elements. Some of his papers on these 

 subjects were published in association with the Rev. J. P. Dale. He 

 was among the earliest to trace the connection between the chemical 

 constitution of a substance and its refractive and dispersive powers. 



Questions of chemical dynamics and on the causes and conditions 

 of chemical change occupied him at various times throughout the 

 whole period of his life as an investigator, and he published a number 

 of papers on the reciprocal decomposition of salts and on the conditions 

 governing their stability. 



In the early part of his career he did a considerable amount of 

 work in pure chemistry, particularly in inorganic chemistry, and 

 especially on the haloid compounds of phosphorus and their ammoniacal 



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