Annual Report of the Council. 215 



practical work. After several years' sickness and suffering 

 he died on April 15th, 1894. Marignac's experimental work 

 in inorganic chemistry began in 1840, with an analysis of 

 " Cobalt Minerals." Soon stereo-chemical studies followed, 

 comprising the determination of the combining weights of 

 eighteen elements, which remain his most appreciated 

 researches. His first publications on the atomic weight of 

 silver, potassium, chlorine, bromine, iodine and nitrogen, in 

 1842 and 1843, induced Berzelius to express the wish that 

 the revision of the atomic weights, already approximately 

 determined by himself with insufficient means, might be 

 carried out by chemists who, like Marignac, " combined 

 exactness and patience in the repetition of experiments 

 with conscientiousness in the statements of the results." 

 Isomorphism was then the leading guide for deducing the 

 atomic weight from the combining weight, and Marignac, 

 as familiar with mineralogy and crystallography as with 

 chemistry, naturally took in this discovery of Mitscherlich's 

 the greatest interest, which led to his numerous masterly 

 crystallographic-chemical investigations. The studies on 

 the rare elements also absorbed much of his time and 

 energy, and those on fluorides, ozone, diffusion, specific 

 heat and expansion of salt solution yielded material for 

 numerous publications, appearing mostly in the Bibliotheque 

 Universelle de Geneve. These investigations, besides the 

 teaching, represent an astounding amount of activity even 

 for a long life, and prove the indefatigable nature of the 

 man. Personally, Marignac was of a retiring disposition, 

 and only appeared in public when performing academical 

 duties. Nevertheless, his merits were well recognised. He 

 was elected a member of many Academies and Societies, 

 and was the recipient of the Davy-Medal and the Prussian 

 Order Pour-le-Merite. His election as an honorary member 

 of this Society took place in 1892. M. J. L. 



In the death of Sir James Cockle we have lost one of 



