166 
In the first part of their Paper the Authors treat of the 
conductibility of mercury, and prove that if the source of heat 
be applied at the upper part of a column of mercury, so as to 
prevent any motion of the solid molecules of the mercury, 
this metal becomes the worst conductor of all known metals ; 
for, silver being 1000, mercury is 54. 
In the second part of their Paper the Authors examine the 
conductibility of the solid and semisolid amalgams prepared 
in equivalent quantities of pure metals with mercury, and 
they show that amalgams may be divided into two classes — 
those containing an excess of equivalents of the amalgamated 
metal, and those which on the contrary contain an excess of 
equivalents of mercury. The first class conduct heat at the 
mean rate of the two metals composing the amalgam, and in 
accordance with the calculated result, as shown by the follow- 
ing table. 
Amalgam of Tin. 
Mercury = 2P63 or 679 
Tin. . . 
. = 13 45 or 
422 
Silver 
= 1000 
Found. 
Calculated. 
Found. 
Calculated. 
6 Sn. Hg. 
10'60 
.... 15-24 . 
... 332 . 
. . 4 <8 
10-30 
15-63 . 
... 322 . 
. . 490 
4 
^ 99 99 
965 
15-88 . 
... 302 . 
. . 498 
o 
° J3 33 
945 
16-30 . 
... 296 . 
.. 571 
~ 33 33 
8-65 
.... 17-19 . 
.. . 271 . 
. . 539 
Sn. Ilg. 
.... 515 
18-56 . 
... 161 . 
.. 582 
„ ~ Hg- 
4-75 
. . . . 19-75 . 
... 149 . 
. . 619 
„ 3 II g. 
4-20 
... 131 . 
. . 63o 
3, 4 Hg. 
3-95 
.... 20-55 . 
. . . 124 . 
... 644 
„ 5 Hg. 
3-65 
20-73 .. 
... 114 . 
. . 650 
The second class, comprising those amalgams containing 
an excess of mercury, conduct heat as if they contained no 
other metal, although its proportions may vary from 10 to 64 
per cent. 
