High Temperatures. 



199 



electric force was impossible. The platinum was the first to 

 be successfully purified, then, sometime after, the rhodium. 

 Thermo-elements from different meltings now show variations 

 of only 1 per cent, when formerly 10 per cent, and more was 

 observed. The wires are also much more homogeneous now 

 than formerly. 



Table XXI. 

 "Time Curves" (MY). 



Min. 



Ag 

 under NaCl 



Ag 

 under NaCl 



Ag 

 in Graphite 



Ag 

 in Graphite 



Cu 

 in Porcelain 



Cu 

 In Porcelain 



Cu 

 in Graphite 



Cu 

 in Graphite 



1 



9423 



8513 



9439 



8766 



10590 



10003 



10680 



10081 



o 



9330 



8599 



9354 



8861 



10475 



10106 



10609 



10179 



3 



9247 



8684 



9255 



8956 



10370 



10183 



10530 



10268 



4 



9130 



8775 



9156 



9016 



10310 



10201 



10455 



10353 



5 



9039 



8857 



9056 



9018 



10240 



10207 



10444 



10409 



6 



9024 



8937 



9018 



9018 



10210 



10210 



10442 



10426 



*l 



9024 



9017 



9017 



9019 



10210 



10210 



10442 



10431 



8 



9023 



9023 



9018 



9019 



10212 



10211 



10442 



10433 



9 



9022 



9024 



9018 



9019 



10214 



10213 



10442 



10436 



10 



9022 



9024 



9018 



9019 



10213 



10213 



10442 



10437 



11 



9022 



9025 



9017 



9022 



10213 



10213 



10443 



10438 



12 



9022 



9026 



9017 



9033 



10214 



10213 



10443 



10439 



13 



9021 



9026 



9016 



9043 



10213 



10214 



10443 



10440 



14 



9021 



S026 



9013 



9055 



10213 



10214 



10442 



10440 



15 



9020 



9026 



9006 



9064 



10212 



10215 



10442 



10441 



16 



9018 



9026 



8976 



9074 



10212 



10215 



10441 



10444 



17 



9014 



9027 



8763 



9121 



10211 



10216 



10439 



10456 



18 



9007 



9028 





9290 



10210 



10219 



10437 



10472 



19 



8990 



9027 







10210 



10227 



10433 



10484 



20 



8800 



9029 







10208 



10245 



10427 



10491 



21 



8600 



9029 







10203 



10268 



10410 



10497 



22 





9029 







10200 



10300 



10342 



10503 



23 





9031 







10193 



10340 



10195 



10509 



24 





9034 







10177 



10460 



10070 



10516 



25 





9037 







10097 





9968 



10564 



26 





9050 







9900 







10720 



27 





9069 







9740 









28 





9232 















29 





9350 















30 



















Since the platinum wire at temperatures above 1000° is con- 

 siderably less stable than the platin-rhodium, much would be 

 contributed in the direction of the durability of the elements 

 if the platinum could be replaced by some related metal or 

 alloy of greater stability. 



