88 



Dr. G. Gore. 



Exp. 9. — 1 oz. of hydrocyanic acid (" Scheele's strength") and 

 40 grs. of potassic cyanide: motion feeble. The directions of motion 

 of the mercury in a capillary of wide bore were the same as those of 

 the current ; but in one of narrow bore an upward current sent the 

 mercury freely down. A downward current had but little effect, but 

 on closing the circuit, or on insulating it immediately after an 

 upward current had been passed, the mercury rose instantly. 



Exp. 10. — 1 oz. of water, 40 grs. of potassic cyanide, and 10 grs. of 

 bicyanide of mercury, formed a very good liquid. The mercury moved 

 in the same directions as the current. 



Exp. 11. — 1 oz. of water and 40 grs. of mercuric cyanide. A current 

 from copper and platinum wires in dilute sulphuric acid produced 

 little or no movement, but the charge from an ebonite electrophorus 

 (the opposite platinum wire of the electroscope being connected "to 

 earth ") caused the mercury to move either up or down in the same 

 direction as the discharge. 



Note. — The electrophorus yielded electricity of much too high tension 

 for use with this instrument, especially if the mercury in the capillary 

 tube was the negative pole ; gas then quickly collected at the meniscus 

 and stopped the action. 



Exp. 12. — 1 oz. of water and 40 grs. of mercuric chloride. This 

 solution was unsuitable. 



Exp. 13. — A mixture of 7 volumes of distilled water and 3 of 

 strongest aqueous ammonia. The movements were very feeble, but in 

 the usual direction, both with the water-cell and the electrophorus. 

 The mercury would only emerge from the end of the capillary in large 

 drops, not in the usual stream of minute ones, probably in conse- 

 quence of the small adhesion of aqueous ammonia to mercury (see 

 "Adhesion of Liquids to Mercury," " Phil. Mag.," August, 1863). 



Exp. 14. — 1 oz. of water and 40 grs. of potassic sulphate. An 

 upward current sent the mercury up freely, and a downward one sent 

 it down. Charging the upper electrode by the electrophorus depressed 

 the mercury as usual ; but charging the lower electrode also depressed 

 it, and more strongly. This exceptional effect was obtained several 

 times. 



Exp. 15. — 1 oz. of water and 40 grs. of potassic borate. The move- 

 ments of the mercury were feeble, but in the usual direction, both 

 with the current and electric discharge. 



Exp. 16. — 1 oz. of water and 40 grs. of acid carbonate of sodium. 

 Free movements of the mercury took place in the usual directions, 

 both by the current and the discharge. 



Exp. 17. — 1 oz. of water and 40 grs. of sulphate of sodium. Feeble 

 movements were produced in the usual directions, both by the current 

 and the discharge. 



Exp. 18. — Dilute sulphuric acids of different strengths, varying 



