1888.] Prof. Roberts- Austen on some curious Properties of 31etals. 367 



WEEKLY EVENING MEETING, 



Friday, May 11, 1888. 



William Crookes, Esq. F.R.S. Vice-President, in the Chair. 

 Professor W. Chandler Roberts-Austen, F.R.S. M.B.L 



Some curious Properties of Metals and Alloys. 



The lecture consisted mainly of experimental demonstrations of the 

 changes induced in metals, either by slight variations in the treat- 

 ment to which they are subjected or by rendering them impure by the 

 addition of small quantities of metals or metalloids. 



Prof. Austen began by pointing out that for centuries the early 

 metallurgists investigated the action of exceedingly small quantities 

 of matter upon masses of metal, and he said that, strange as it may 

 seem, the promulgation, in 1803, of Dalton's atomic theory threw a 

 flood of light upon chemical phenomena, but cast into shade such 

 investigations as those of Bergman which dealt with influences of 

 " traces " upon masses, and the authority of Berthollet was not sufiicient 

 to save them from neglect. In this eventful year for science, 1803, 

 the latter published his essay on chemical statics, in which he stated, 

 as a fundamental j)roposition, that in comj)aring the action of bodies 

 on each other, which depends " upon their affinities and mutual 

 proportions, the mass of each has to be considered." * His views 

 were successfully contested by Proust, but, as Lothar Meyer says, 

 the influence on chemistry of the rejection of Berthollet's views was 

 remarkable : " All phenomena which could not be attributed to fixed 

 atomic proportions were set aside as not truly chemical, and were 

 neglected. Thus chemists forsook the bridge by which Berthollet 

 had sought to unite the sister sciences, physics and chemistry." 

 Fortunately, however, in this country there was one chemist who had 

 followed up the line of work indicated by the early metallurgists, 

 for in 1803, the same year as that in which both Berthollet's essay 

 and Dalton's atomic theory were published, Charles Hatchett f com- 

 municated to the Royal Society the results of a research which he 

 had conducted, with the assistance of Cavendish, in order to ascertain 

 " the chemical efiects produced on gold by difierent metallic substances 

 when employed in certain " (often very small) " proportions as alloys." 



Allusion was then made to the evidence of the passage of metals 

 into allotropic states, and it was shown that although the importance 

 of the isomeric and allotropic states was abundantly recognised in 

 organic chemistry, it had been much neglected in the case of metals. 



* English edition (bv M. Farrell, M.D.), 1804, p. 5. 

 t Phil. Trans, vol. xciii. p. 43, 1803. 



