the Tliermo-Electric Properties of Liquids. 521 



2\ oz. of pure concentrated nitric acid. Platinum plates. Current 

 f 48. Cold water produced a strong J current. (Compare No. 138). 



No. 26. The same mixture. Gold plates. Current f 53. Cold 

 water reversed the current strongly. 



No. 27. The same mixture. Palladium plates. Current f 56. Cold 

 water produced a very strong J current. The upper plate was found 

 corroded after the experiment. Remarks. A comparison of the results 

 of Experiments Nos. 25, 26, and 27, with those of the three imme- 

 diately preceding ones, shows the effect of the free acid in increasing 

 the negative condition of the hot plate. 



No. 28. 14 oz. of water and 2\ oz. of pure concentrated nitric acid. 

 Platinum plates. Current j 20 J at 160° P., and 16 J at 210° F. Cold 

 water reversed the current strongly. (Compare No. 119.) 



No. 29. The same mixture. Gold plates. Current j 24J. 

 Remarks. A comparison of the last eight experiments shows that a 

 mixture of an aqueous solution of cupric nitrate with one of nitric 

 acid yields stronger currents than either solution alone. 



No. 30. A strong aqueous solution of chloride of chromium. Gold 

 plates. Current f 44 at 200° F., and 42 at 210° F. This liquid had 

 not been pre-boiled, and therefore many air-bubbles accumulated 

 against the hot plate, but appeared to only slightly decrease the 

 amount of deflection. Cold water produced a very strong \ current. 



No. 31. The same solution. Platinum plates. Current j 45 at 

 180° F., and 42 at 210° F. Cold water produced a very strong \ cur- 

 rent. (Compare No. 123.) 



No. 32. The same solution. Palladium plates. Current J 63. Cold 

 water diminished the amount of deflection. Both the plates were a 

 little corroded after the experiment, and each equally so. Repetition 

 of this experiment yielded similar effects. (Compare Nos. 18 and 

 60.) 



No. 33. 14 oz. of water and 1 oz. of acid chromate of potassium. 

 Platinum plates. Current J \\. Cold water reversed the current. 



No. 34. The same mixture. Gold plates. Current J 4| at, 200° F. 

 Cold water produced a feeble } current. 



No. 35. The same mixture. Palladium plates. Current | 5^. Cold 

 water produced a feeble j current. 



No. 36. The same mixture, with 1 oz. of dry crystals of chromic 

 acid added. Platinum plates. Current J 4^. Cold water first 

 slightly increased and then, to a large extent, decreased the current. 

 (Compare No. 124.) 



No. 37. The same mixture as in No. 36. Gold plates. Current 

 | \\. Cold water feebly reversed the current. 



No. 38. The same mixture as in No. 37. Palladium plates. Current 

 1 3 at 120° F., and \ 20 at 210° F., and gradually increased to 30 by 

 continuance of heat. Cold water first slightly increased and then 



vol. xxvii. 2 M 



