254 Dr. G. Gore. Delations of Heat to Voltaic and 



Table I (continued). 



* Indicates a gradual reversal with one metal only. 



t Indicates that a temporary reversal occurred when the current* from the two 

 contiguous metals (i.e., the one marked and the one above it) were opposed. 

 J Magnesium was first negative, then positive, then negative 38 deerees. 

 Magnesium was first positive, then negative, then positive 30 degrees. 



Remarks. Of the foregoing cases, only those in which the metals 

 are not at all corroded, are entirely thermo-electric, the remainder are 

 concrete ones involving the additional influences of ordinary chemical 

 corrosion and of voltaic action, and this fact must be remembered. 



The currents were feeble in solutions of hydrochloric, formic, and 

 dextro-tartaric acids, notwithstanding that the corrosion of the more 

 electro- positive metals appeared to be as strong as usual, and the 

 currents were so weak with cadmium in formic, and cadmium and 

 gold in tartaric acid, that the positions of those metals as given in 

 columns 13 and 14 are uncertain. The direction of the currents 

 obtained with aluminium, also with magnesium, in a solution of one 

 grain of Isevo-tartaric acid per ounce of water, was the same as in a 

 solution of the same strength of ordinary or dextro-tartaric acid. By 

 opposing to each other also the thermo-electric currents from those 

 two solutions either with aluminium or magnesium, that from the one 

 of the Ifflvo-acid was in each case found to have slightly the greatest 

 electric potential. 



In some separate experiments, the strength of thermo-electric 

 current from platinum at 60 and 160 F., in a solution of potassic 

 cyanide, varied directly as the strength of the liquid, the deflection 



