1879.] 



Aqueous Solutions with Mercurial Electrodes. 



479 



the second series ; phosphate of ammonium, sulphate of ammonium, 

 &c, are also changed in position. Such changes were probably 

 affected by the circumstance, that whilst in the first series the elec- 

 trodes were 81 millims. diameter ( = 5,153 sq. millims. of surface), and 

 the current from a single apparatus circulated through a continuous 

 double length of wire in the coil of the galvanometer, in the second series 

 the electrodes were only 75 millims. diameter (=4,418 sq. millims.), 

 and the current from a single apparatus circulated through a single 

 half length of the coil. The temperatures at which the deflections 

 were noted were also different in the two series. The surface of one 

 electrode in the smaller apparatus was about and in the larger one 

 ^ of that of one of the platinum electrodes in the apparatus already 

 referred to (see foot note, p. 474). 



Difference of amount 



1. Sulphate of ammonium 



2. Nitrate of potassium 



3. Phosphate of ammonium 



4. Sulphite of sodium (50 grs.) 



5. Carbonate of sodium 



6. Carbonate of potassium 



7. Sulphate of potassium 



8. titrate of strontium 



9. Phosphate of sodium 



10. Borax 



11. Selenate of sodium 



12. Nitrate of barium 



13. Nitrate of sodium 



14. Pormiate of sodium (100 grs.) 



15. Microcosmic salt (50 grs.) 



16. Pormiate of sodium (50 grs.) 



17. Pormic acid (80 minims) 



18. Nitrate of ammonium 



19. Sulphate of sodium 



20. Sulphite of sodium (10 grs.) 



21. Microcosmic salt (100 grs.) 



22. Boracic acid 



of deflection. 



1-0 + 



3-0 



3-0 



0- 75 



1- 

 1-5 

 0'25 

 0-25 



0- 25 

 15 



1- 5 



0- 25 

 10 



1- 

 0-75 



0- 75 



2- 



1- 5 

 0-25 

 0-25 



2- 



23. Ammonia alum (50 grs.) yery sligllt _ 



24. Cyanide of potassium (2^ grs.) .... q.-~ 



25. Ammonia alum (100 grs.) ^.q 



2G. Hyposulphite of sodium -^-Q 



27. Cyanide of potassium (5 grs.) 



28. Cyanide of potassium (50 grs.) 2-25 



29. Cyanide of potassium (100 grs.) .... 



