298 Mr R. Adie on Electrical Experiments. 



known, even those most rare. In the present case, it cannot be al- 

 together devoid of interest to trace to its first source the enormous 

 quantities of phosphoric acid, for the most part locked up in a tem- 

 porarily insoluble condition in the vegetable and animal kingdoms, 

 and in the various strata of calcareous and sedimentary deposits, in 

 the formation of which, organized beings have played so prominent 

 and important a part. 



An Account of Electrical Experiments. By Mr R. Adie, Liver- 

 pool. Communicated by the Author. 



Among the details of the experiments as originally drawn up by 

 me for publication, in the 70th and 71st Numbers of Jameson's 

 Philosophical Journal, I had some which shewed a molecular action 

 in the joint of M. Pelletier's cross, when subjected to the continued 

 influence of a feeble electrical current for six w^eeks. Ultimately, 

 these experiments were withdrawn from the first series submitted for 

 the consideration of your readers ; for I failed in an attempt to detect 

 any action on the galvanometer, from the slow mechanical fracture 

 of a thermo joint, and the disappointment in this experiment made 

 me desirous of examining more at leisure the details of the subject. 



The results I have now to offer, appear to me to lead by steps to 

 the explanation of the sources of the electrical currents noticed by M. 

 Pelletier ; but I regret that they do not confirm an observation de- 

 duced from his original experiments, namely, that a current of elec- 

 tricity, in passing from one metal into another, can, under some cir- 

 cumstances, lower the temperature of the joint below that of the sur- 

 rounding atmosphere ; or, in other words, can produce cold. It will 

 be seen that a given current of electricity may heat a joint 12°, by 

 passing through it in one direction, and only 2° when passed in an 

 opposite direction ; but in no instance is the temperature ever re- 

 duced below that of the apartment where the investigations are car- 

 ried on. Another result which these experiments go to prove, and 

 to my mind the more important of the two, is, that an electrical 

 current, in passing across any medium, heats the part where it en- 

 ters higher than the part where it quits the medium. 



35. To the extremities of a galvanic battery of ten pairs of zinc 

 and silver plates, superficies of each plate in action about 50 inches, 

 two small platina capsules were attached by bands or ribbons of cop- 

 per, so that these capsules could be used as a pair of decomposing 

 poles. They were then inserted to about two-thirds of their depth, 

 in acidulated water, with nearly a superficial inch of surface in ac- 

 tion as a decomposing pole. On completing the circuit, a brisk de- 

 composition commenced, which kept the platina surfaces well covered 

 with gas bells. Inside the capsules, I had two delicate thermometers, 



