300 



The products of the action of chromic acid on sycocerylic alcohol , 

 were a white crystalline neutral substance and a body crystallizing 

 in large flat prisms. The latter appears to be the sycocerylic 

 aldehyde. 



II. " Analytical and Synthetical Attempts to ascertain the cause 

 of the differences of Electric Conductivity discovered in 

 Wires of nearly pure Copper " By Professor WILLIAM 

 THOMSON, F.R.S. Received December 22, 1859. 



Five specimens of copper wire No. 22 gauge, out of a large number 

 which had been put into my hands by the Gutta Percha Company 

 to be tested for electric conductivity, were chosen as having their 

 conductivities in proportion to the following widely different numbers, 

 42, 71*3, 84*7, 86'4, and 102 ; and were subjected to a most careful 

 chemical analysis by Professor Hofmann, who at my request kindly 

 undertook and carried out what proved to be a most troublesome 

 investigation. The following report contains a statement of the re- 

 sults at which he arrived : 



''Royal College of Chemistry, 

 March 10th, 1858. 



"SiR, I now beg to communicate to you the results obtained in 

 the analysis of the several varieties of copper wire intended for the use 

 of the Transatlantic Telegraph Company, which you forwarded to 

 me for examination. 



" I have limited the inquiry to a minute qualitative analysis of 

 the wires, to a very accurate determination of the amount of copper, 

 and an approximative determination of the amount of oxygen. The 

 qualitative analysis has been repeated several times with as consider- 

 able quantities as the amount of material at my disposal permitted. 

 The quantitative determinations of fche. copper have been made with 

 particular care, and after a lengthened , scrupulous inquiry into the 

 limit of accuracy of which the method employed is capable, I am 

 convinced that the true per-centages of copper cannot be more than 

 (H per cent, either above or below the means of the determinations, 

 the details of which I give you in the Appendix. 



" The following Table contains the results furnished by analysis : 



