1880.] Thermo-Electric Behaviour of Aqueous Solutions, fyc. 247 



difference of strength, of the liquids, except in the instance of 

 Amnionic alum ; in that case the neutral point occurred at a lower 

 temperature with the stronger solution. 



The following is the order obtained by arranging the above results 

 in a series, with the solution at the top in which hot platinum was most 

 positive at 180° F., and that at the bottom in which it was most negative. 

 The liquids above the horizontal line are those in which the hot metal 

 was positive, below it are placed those in which it was negative : — 



1. Cyanide of potassium (120 grs.) ll'O + 



2. Cyanide of potassium (60 grs.) 8*25 



3. Carbonate of potassium 8'0 



4. Phosphate of ammonium 6*0 



5. Carbonate of sodium 5 "5 



6. Hyposulphite of sodium 5*25 



7. Formiate of sodium (120 grs.) 5'0 



8. Sulphite of potassium 5*0 



9. Sulphate of potassium 4 - 



10. Formiate of sodium (60 grs.) 4*0 



11. Sulphite of sodium (60 grs.) > 3'5 



12. Sulphate of ammonium 3*5 



13. Phosphate of sodium 3*0 



14. Borax 2*0 



15. Cyanide of potassium (6 grs.) 2*0 



16. Formic acid (96 minims) 1*5 



17. Microcosmic salt (120 grs.) l'O 



18. Nitrate of potassium l'O 



19. Nitrate of strontium l'O 



20. Cyanide of potassium (3 grs.) . .- l'O 



21. Sulphite of sodium (12 grs.) l'O 



22. Formic acid (48 minims) l'O 



23. Nitrate of ammonium •75 



24. Microcosmic salt (60 grs.) '75 



25. Sulphate of sodium » *75 



26. Selenate of sodium '75 



27. Nitrate of sodium "5 



28. Nitrate of barium '5 



29. Boracic acid faintly positive. 



30. Ammonia alum (60 grs.) '75 



31. Selenic acid (12 minims) *75 



32. Selenic acid (24 minims) l'O 



33. Ammonia alum (120 grs.) l'O 



34. Sulphuric acid (1 in 80) * 3'25 



35. Sulphuric acid (1 in 20) 3' 75 



36. Sulphuric acid (1 in 40) 4"25 



