NATURAL PHILOSOPHY. 123 



general explanation, "tliatthe theory of the fly requires a different 

 expression for an aerial as compared with a liquid dielectric, its be- 

 havior is also different in air of different densities : and also when 

 wholly and partially inclosed ; also, when the points are covered ; 

 and even then there is a difference in action, in the presence of flame," 

 from which we infer that its behavior is so modified by circumstances 

 that no one expression represents the law governing its action. 



ELECTRICITY IN THE TIIEATMENT OF HYDROPHOBIA. 



The Journal de Physique contains a remarkable case of recovery 

 from hydrophobia by galvanism, extracted from a " Report presented 

 to the Academy of Turin," by Signor Eandi. A man presenting all 

 the symptoms of hydrophobia (he had been bitten by a mad dog) 

 was brought to Dr. llossi, who, observing that he could not bear the 

 sight of water, nor that even of shining bodies, provided in another 

 room a pile consisting of 50 pairs of plates of silver and zinc, inter- 

 mixed with 50 pieces of pasteboard moistened with a solution of muri- 

 ate of ammonia. He employed slips of brown paper moistened, as a 

 conductor on which the naked feet of the patient were placed, and at 

 the moment when he opened his mouth to bite, one end of the arc was 

 thrust into it, while the other communicated with the pile. The pa- 

 tient suffered a great deal from this operation, which, after several 

 shocks, weakened him so much that he could no longer support it. 

 Being stretched out on the floor, he was then galvanized with ease ; 

 the operation made the sweat run from him in drops. This treatment 

 was continued for several days, and resulted in the complete recovery 

 of the patient. This cure, says the report, was effected in the pres- 

 ence of several persons. This was about 12 years ago, if I mistake 

 not. The experiments lately made at the Hospital of Lernberg were 

 satisfactory in so far as the application of electricity had the effect of 

 procuring a temporary relief, though the patients were not saved 

 thereby. Dr. Essrogen, who relates this fact in the Zeitschrift fur 

 practische Heilkunde, is of opinion that had the application of elec- 

 tricity been continued, a complete cure would have been brought 

 about. Phil. Med. and Surg. Rep. 



NEW CALORIC BATTERY. 



At a late meeting of the Inventor's Institute, Mr. James Dickson read 

 an interesting paper on " Certain Inventions for inducing the Economical 

 and Efficient Production of Voltaic Electricity for lighting Streets and 

 other Purposes." The object of the paper was to explain the means oy 

 which electricity could be readily and economically produced. The his- 

 tory of Voltaic Electricity was carefully traced from the time of Volta, 

 from whom this form of electricity took its name, to the present time, 

 special mention being made of Grove's, Snell's, the Maynooth and other 

 batteries, which from time to time have been looked upon as vast im- 

 provements upon their existing apparatus. The theories of Mayer 

 Joule were referred to, as well as the researches of Prof. Tyndall, whose 

 " Heat as a Mode of Motion " contains so much valuable information on 

 the subject. He considered- that the rapidity of the vibration of the 

 atoms in a conductor was exactly in proportion to its conducting power, 

 and explained that, whilst a battery was producing light and heat, less 



