360 
MR.  GRACE  CALVERT  AND  'MR.  R.  JOHNSON  ON  THE  RELATIVE 
The  above  two  series  of  alloys  are  the  only  ones  which  conducted  heat  as  above 
stated ; and  from  experiments  which  will  be  described  fuidher  on,  we  believe  that  the 
metals  composing  these  alloys  are  simply  mixed  and  not  combined  together. 
Alloys  containing  an  excess  of  the  worse  conducting  Metal. 
The  study  of  this  class  of  alloys  being  most  interesting,  we  have  made  many  experi- 
ments in  order  to  discover  why  the  presence  of  one  metal  completely  annihilates  the 
conducting  power  of  the  other,  especially  when  the  latter  is  the  better  conductor  of  the 
two. 
The  following  series  vrill  illustrate  the  above  statement. 
Lead  and  Antimony. 
Formula  of  the  alloys 
Found 
Calculated. 
Silver  = 
= 1000. 
and  per-centage. 
(Mean). 
Found. 
Calculated. 
lPb=6l-6ll 
lSb=38*39j 
6-05 
8-00 
190 
j 
251  j 
lPb=  47-601 
2Sb=  52-40 
5-90 
7-57 
185 
237  ] 
lPb  = 34-861 
3Sb=65-14  j 
5-85 
7*18 
184 
225 
lPb  = 28-63l 
4Sb=71'37j 
5-70 
6-99 
179 
219 
lPb  = 24-301 
5Sb=75-70j 
5-70 
6-85 
179 
215  I 
It  wiU  be  perceived,  on  looking  over  the  results  obtained,  that  all  these  alloys  conduct 
heat  almost  as  if  the  square  bars  examined  were  composed  of  piu’e  antimony,  the  con- 
ducting power  of  which  is  6T2 ; for  if  lead,  which  has  a conducting  power  of  9.TT,  had 
influenced  the  passage  of  heat  through  the  bars,  the  conducting  power  of  the  alloys 
would  have  been  much  higher,  as  shown  by  the  column  of  theoretical  conductibility. 
The  same  results  were  obtained  with  the  following  series  composed  of  bismuth  and 
antimony : — 
Antimony  and  Bismuth. 
Silver 
= 1000. 
Formula  of  the  alloys 
Found 
Calculated. 
and  per-centage. 
(Mean). 
Found. 
Calculated. 
lSb= 37-74] 
IBi  = 62-26  J 
1-97 
3-52 
62 
110 
lSb=23-26 
2Bi  = 76-74 
1-87 
2-92 
59 
91 
186=16-811 
3Bi  =83-19  J 
1-90 
2-64 
59 
83 
lSb=13-l71 
4B!  =86-83  J 
1-50 
2-47 
47 
77 
lSb=10-82l 
5Bi  =89-18  J 
1-55 
2-39 
48 
75 
