I 4 



18 *_H 



We try this several tirm 

 several ways, with different 

 degrees of heat, and different 

 sized bars ; also with shot 

 I inch apart, instead of peas 

 at J^ inch, but always with a 

 result closely similar. Singu- 

 emnigh, we find the heat 

 takes from twice to four times 

 as long to travel to the last 

 pea that falls from the Iron 

 bar, as to the last pea that falls 

 from the ZA bar. 



;. 17 shows the Iron and 

 ZA bars put side by side, and 

 the proportionate rate the 

 heat travels upon each, as it 

 arrives at a, b y c, d t etc., on 

 each of the bars, at about the 

 same time. 



Fig. 18. 



idea 



1 8 gives a very rough 

 of the proportionate 



