28 
Mr. Davy's Lecture on some 
Thus, when a fresh leaf-stalk of the polyanthus, about 2 
inches long, was made to connect a positively electrified tube 
containing solution of nitrate of strontites, and a negatively 
electrified tube containing pure water. The water soon be- 
came green, and gave indications of alkaline properties, and 
free nitric acid was rapidly separated in the positive tube. After 
ten minutes, the alkaline matter was examined ; it consisted 
of potash and lime, and as yet no strontites had been carried 
into it : for the precipitate it gave with sulphuric acid readily 
dissolved in muriatic acid. In half an hour strontites, however, 
appeared ; and in four hours it formed a very abundant in- 
gredient of the solution. 
A piece of muscular flesh of beef, of about 3 inches in 
length and half an inch in thickness, was treated in the same 
way as the medium of communication between muriate of 
barytes and distilled water. The first products w^ere soda, 
ammonia, and lime; and after an hour and a quarter, the 
barytes was very evident. There was much free oxymuriatic 
acid in the positively electrified tube, but no particle of 
muriatic acid had passed into the negative tube, either from 
the muriatic solution or from the muscular fibre. 
VI. Some general Observations on these Phenomena, and on the 
Mode of Decomposition and Transition. 
It will be a general expression of the facts that have been 
detailed, relating to the changes and transitions by electricity, 
in common philosophical language, to say, that hydrogene, 
the alkaline substances, the metals, and certain metallic oxides, 
are attracted by negatively electrified metallic surfaces, and 
repelled by positively electrified metallic surfaces ; and con- 
