J50 INCREASE OF TEMPERATURE BY GALVANISM. 



two troughs, each 25 plates, each plate 36 inches surface ; 

 with diluted nitrous acid I had made use of four days be- 

 fore, now adding a little more acid. 

 Descrinion of ^ s ^ c a PP aratus I made use of to contain the water is 

 the apparatus, one of my forming and making, it will perhaps be necessary 

 to describe it, before I relate the result of the experiment. 

 Let A B C D, PL IV. Fig. 7. represent a glass tube ca- 

 pable of containing Ifoz. of distilled water ; EF a brass 

 cap, through which passes a screw G, to which can be at- 

 tached a platina or other wire ; and by taking the screw out 

 another sort of wire may be fixed, as is represented by O : 

 H a box with leather through which the thermometer I 

 passes, and then screws on tight, graduated on the tube; 

 KL a basin, in which the tube rests when filled with dis- 

 tilled water ; M a neck, which may be fitted in any conve- 

 nient place to support the apparatus, screwing through the 

 basin, and terminating in a pair of forceps, into which may 

 be inserted any sort of wire. 



On forming a connection at G with one end of the bat- 

 tery, and at M with the other end, the galvanic fluid will 

 pass through, and decompose the water in the tube; and 

 the thermometer will indicate the temperature. 



Having explained the apparatus, I proceed to the expe- 

 riment. 



The zink end of my battery communicated with G, 

 which was provided with a platina wire O. The inferior 

 platina wire P was connected with the copper end of the 

 battery. 

 Elevation of ^ stream °f S as was projected downwards half an inch 



temperature from the lower end of the wire O. The wire P became 

 grces ' oxided very fast ; and the thermometer, which was at the 

 commencement of the experiment 54°, rose to 80°. When 

 I had decomposed l|oz. of water, I disengaged the appa- 

 ratus, and tested the water (which was forced from the tube 

 into the basin) with the nitrate of silver, which gave a white 

 appearance. 

 Muriatic acid. From this appearance I conclude muriatic acid was formed ; 

 but what furnishes its constituent parts? surely neither the 

 glass tube, the platina wires, nor the basin. As we cannot 

 suppose that either of tb.ese furnished it, we must look for 



its 



