354 
ME.  CEACE  CALVEET  A:s^D  JIE.  E.  JOIDsSOX  OX  THE  EELATITE 
Table  (continued). 
Temperature 
of  the 
50  cub.  cent,  of 
water  before 
beginning. 
Temperature 
of  the 
50  cub.  cent, 
after 
15  minutes. 
ConductibHity 
found. 
r 18-4 
39-0 
20-6  1 
19-9 
40-2 
20-3 
> 
18-5 
38-9 
20-4 
ri9-6 
39-8 
20-2  ' 
19-2 
39-1 
19-9 
1 
14-0 
35-0 
20-0  J 
|■20-6 
40-0 
19-4  1 
1 
[20-8 
40-2 
19-4  J 
r 
r 18-0 
.36-5 
18-5  1 
1 
[16-5 
34-8 
18-3  J 
r 
J 
18-70 
32-6 
13-9 
[ 
1 
[19-05 
33-0 
13-90  J 
r 
1 
20-5 
34-0 
13-55  1 
1 
1 
[21-2 
34-6 
13-4  J 
r 
i 
ri5-2 
27-8 
12-6 
[ 
1 
15-5 
28-2 
12-7 
r 
J 
r 15 
27-1 
12-1  1 
1 
1 
[14 
26-2 
12-2  J 
r 
J 
14-2 
25-9 
11-7  1 
1 
1 
[ 14-1 
25-7 
11-6  J 
r 
J 
[14-9 
26-4 
11-50  1 
1 
1 
[15-6 
27-0 
11-40  J 
r 
1 
[20-5 
29-70 
9-20  1 
t 
1 
18-3 
27-45 
9-15  J 
r 
J 
14-6 
21-5 
6-9  1 
1 
1 
14-3 
21-1 
6-8  J 
r 
J 
19-2 
25-30 
6-10  1 
1 
1 
[18-9 
25-05 
6-15  J 
r 
1 
19-0 
21-00 
2-00  1 
1 
1 
18-3 
20-20 
1-90  J 
r 
Name  of  the  metals. 
Zinc  (rolled) 
Zinc  (cast  vertically) 
Zinc  (cast  horizontally) 
I Cadmium  
i 
i Malleable  iron  
i Tin 
I Steel  
I Platinum  
i Sodium  
I 
i Cast  iron  
Lead  
Antimony  (cast  horizontally) 
Antimony  (cast  vertically)  ... 
Bismuth  
Mean. 
20-45 
20-03 
19-40 
18-40 
13-92 
13-45 
12-65 
12-15 
11-65 
11-45 
9-17 
6-85 
6-12 
1-95 
Conductibilitv. 
! Silver  =1000. 
641 
628 
608 
577 
436 
422 
397 
380 
365 
359 
287 
215 
192 
61 
From  the  details  given  in  describing  the  apparatus  used  in  our  experiments  and  the 
methods  followed,  it  will  be  easy  to  perceive  that  for  the  solid  metals  we  always 
employed  square  bars,  1 c.  m.  square  and  6 c.  m.  long.  These  bars  were  always  cast  of  a 
larger  size  than  required,  and  were  filed  down  to  the  exact  dimensions.  For  mercury 
and  sodium  we  were  obliged  to  have  recourse  to  other  methods  of  operating.  We 
employed  a very  thin  sheet-iron  box,  the  internal  dimensions  of  which  were  exactly 
those  of  the  square  metallic  bars  which  we  usually  employed.  To  admit  the  mercury, 
there  was  in  the  middle  of  one  of  the  longitudinal  surfaces,  a small  hole  4 millims.  in 
diameter,  and  when  full  of  mercury  the  hole  was  stopped  with  a little  thick  caoutcliouc 
varnish.  The  box  was  then  weighed,  by  which  it  was  easy  to  ascertam  if  it  was  quite 
full.  It  was  then  introduced  into  the  two  vulcanized  india-rubber  boxes,  and  the  con- 
ducting power  of  the  mercury  and  box  determined.  By  subtracting  the  special  con- 
ducting power  of  the  box  (which  had  preriously  been  ascertained)  from  the  total  con- 
ducting power  of  the  box  and  mercury,  the  difference  was  the  conducting  power  of  the 
mercury  as  given  above.  We  operated  in  the  same  way  -with  sodium,  with  this  differ- 
ence, that  we  melted  the  sodium  under  benzine,  and  whilst  fluid  filled  the  box  with  it. 
Of  course  we  cannot  pretend  that  the  figures  which  we  give  in  these  two  instances  repre- 
