362 . REPORT — 1864. 



Results foe Gold-silver allot, 



Eesistanee of metre-gramme of wire No. I. 1-00000. 

 „ ., No. II. 0-99963. 



No. III. 1-00017. 

 No. IV. 1-00036. 

 No. V. 0-99996. 



Meecxjrt. 



Three tubes were filled with mercury and their resistance taken. 



Tubes Nos. I. and II. with distilled mercury treated with nitric and sul- 

 phuric acid. 



Tube No. III. with mercury distilled from a specimen which contained a 

 small quantity of gold. 



The lengths of the column are given below in their order. 



Several other kinds of mercury were tried in one and the same tube, and 

 the resistances found to bo the same within two or three-hundredths per cent. 



Sixteen' tubes were obtained, picked from a great nvmiber, and of these the 

 three best ones were taken. No. I. was not so good a tube as the others, as 

 the outside was uneven, rendering it impossible to calibrate it with very great 

 accuracy. 



