ON ELECTRO-CHEMICAL EXPERIMENTS. ] JJ 



piece of potash, not moistened, a>id make a communicator* 

 to its upper surface by a silver wire from ihe positive sur- 

 face. In the space of about a minute, or less, metallic 

 globules appear near the negative surfaces. (Some of these 

 inflame, but for the most part they become covered with a 

 crust of potash, which defends them from the farther action 

 of the air). As soon as these globules appear, they should, 

 be attentively watched, and the instant they cease to grow 

 larger, removed on the point of a silver knife, and plunged 

 into a watch glass filled with naphtha; or if the experiment 

 is intended merely to show their production, they may be 

 immersed in water as they are removed, when each globule 

 •will produce a vivid inflammation. 



When the circumstances I have mentioned are strictly Sometimes n© 

 attended to, the phenomena are usually as I have now de- s o ° u eb < * p " 

 scribed ; but it sometimes happens, that no globules ap- 

 pear: in this case, the communication should be still con- 

 tinued for five or ten minutes, when the potash being taken 

 from the spoon, the side which was in contact with it will 

 be found studded with metallic globules, which may be re- 

 moved as before directed. 



. By following this mode of operation, I soon found, that a The decompo- 

 much lower power than I had at all suspected was adequate to sitlon effected 

 the production of a distinct result. With a glass-partitioned. J 

 battery of 50 pairs of 4 inch plates, the metallic base was 

 produced in sufficient quantity to evince its principal pro- 

 perties with considerable ease. This result induced me to 

 try, if it might not be effected by a lower power ; and I 

 have actually found, that, by carefully conducting the pro- 

 cess, very distinct globules may be produced by a battery 

 of 50 plates, of only 3 inches diameter, which battery has 

 also the disadvantage of having been much corroded by 

 former operations. The metallization of the alkaline earths 

 and of ammonia by amalgamation with mercury may be 

 also effected by the last described battery ; so that even this 

 small power, properly directed, is sufficient to afford a satis- 

 factory illustration of the principal phenomena for the indi- 

 vidual gratification of the chemical inquirer. 



The transfer of acid and alkali may be very readily shown Transfer of acid 

 by an apparatus of this size. The most striking mode of and alkali. 



Vol. XXIV— Nov. 1809. N illustrating 



