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lin’s Views. Polarity of a series of Jars. Electrometers applicable 
to measuring the intensity of the charge of a Jar. Experiments in 
reference to the Theory of the Leyden Jar. Magnetic Phenomena 
analagous to those of induced electricity. Of the Electrophorus, and 
the permanent source of its electricity—states of the upper and lower 
plates. Of Electrical Batteries. 
Lecture V. March 6. 
Excitation of Magnetism observed in wires transmitting electricity ; 
independent effects of quantity and intensity. Experiments on the 
perforation, disruption, and ignition of various substances by Elec- 
tricity. Experiments of Cavendish, Priestley, Bennet, and Volta, in 
relation to the Chemical agencies of Electricity. Dr. Wollaston’s 
Researches upon this subject. Natural phenomena dependent upon 
or connected with Electrical Excitation. Applications of Conductors 
to houses, steeples, ships, and powder magazines. 
Lecture VI. March 13. 
Recapitulation of the principal subjects discussed in the preceding 
Lectures, as illustrating other sources of Electricity, and especially 
that of the contact of dissimilar metallic and other conducting bodies. 
Experiments of Galvani—of Volta. Construction of the Voltaic 
Pile—the Couronne des Tasses—the Battery. De Luc’s Electrical 
Column—its importance in demonstrating the source of electricity in 
Volta’s Pile. Influence of chemical agents in these arrangements. 
Sir H. Davy’s early Discoveries in this department of science. In- 
fluence of the size of the plates, and of their number upon the electric 
excitement. 
Lecture VII. March 20. 
Proofs of the identity of Voltaic and common Electricity. Various 
forms and constructions of the Pile and Battery. Best construction 
suggested by Dr. Wollaston, Experiments on the ignition and fusion 
of substances with large Voltaic Batteries. Various causes which 
influence the conducting powers of Metallic Wires referred to in 
illustration of Sir H. Davy’s Researches, Passage of Voltaic Elec- 
tricity through a vacuum. 
