by the Immersion of unequally Heated Metals in Liquids. 15 



58. Sulphite of Potash. — 4 ounces of distilled water and 100 

 grains of sulphite of potash, solution pre-boiled ; hot metal posi- 

 tive. Retried it after absorption of some air; same result, but 

 in greater degree. Weak alkaline reaction with test-paper. 



59. Sulphate of Potash. — 4 ounces of distilled water and 100 

 grains of sulphate of potash, liquid pre-boiled ; hot metal posi- 

 tive. Retried after it had absorbed some air ; same I'esult, but in 

 a less degree. Liquid exhibited neutral reaction with test-paper. 



60. Chlorate of Potash. — 4 ounces of spring water and 100 

 grains of chlorate of potash ; hot metal feebly negative. Retried 

 with liquid pre-boiled ; hot metal again feebly negative. Tried 

 again with distilled water and solution pre-boiled; hot metal 

 feebly positive. Allowed the latter solution to absorb some air ; 

 the hot metal was still positive, but in a less degree. The liquid 

 gave a very faint acid reaction with litmus-])aper. In this case, 

 as in that of hydrochlorate of ammonia (54), the impurities of 

 spring water evidently interfered and reversed the electric rela- 

 tions of the plates. 



61. Nitrate of Potash. — 4 ounces of spring water and 100 

 grains of nitrate of potash ; hot metal positive. Retried with 

 distilled water and liquid pre-boiled ; same result. Tried again 

 with some air absorbed ; same result, but in a less degree. Faintly 

 acid reaction with litmus-paper. 



62. Cyanide of Potassium. — 4 ounces of distilled water and 

 100 grains of cyanide of potassium, liquid pi"e-boiled ; hot metal 

 strongly positive. Retried the liquid after it had absorbed some 

 air ; same result. Strongly alkaline reaction with litmus-paper. 

 Probably chemical action contributed towards the strength of this 

 result. 



63. Tartrate of Potash. — 4 ounces of distilled water and 100 

 grains of tai'trate of potash, liquid pre-boiled ; hot metal positive. 

 Retried after it had absorbed some air; same result. Weak 

 alkaline reaction. 



64. Bitartrate of Potash. — 4 ounces of distilled water satu- 

 rated at 63° F. with bitartrate of potash, liquid pre-boiled ; hot 

 metal negative. Retried after exposure to the atmosphere a few 

 hours ; same result. Acid reaction with litmus-paper. 



65. Caustic Soda. — 4| ounces of spring water containing 100 

 grains of anhydrous soda, liquid pre-boiled ; hot metal positive. 



66. Carbonate of Soda. — 4 ounces of spring water and 100 

 grains of crystallized carbonate of soda ; hot metal positive. 

 Retried with the solution pre-boiled ; same result. Tried again 

 with distilled water and the solution pre-boiled; same result. 



67. Jiiborale of Soda. — 4 ounces of spring water and 50 grains 

 of biborate of soda ; hot metal jjositive. Retried with distilled 

 water and 60 grains of the salt, liquid pre-boiled; same result. 



