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THE POPULAR SCIENCE MONTHLY. 



imperial castle. These performances were also honored by the 

 presence of the Empress Maria Theresa. The imperial couple 

 were highly pleased with the experiments, and, to show their 

 esteem for Divis, they presented him with two heavy golden 

 medals with their busts engraved upon them. 



In 1750 Divis demonstrated his superior knowledge of elec- 

 tricity in an amusing way. Father Francis, a learned Jesuit, was 

 about to make some experiments with his electrical machine at 

 the Vienna court. While he was making some preliminary re- 

 marks, the Bohemian scholar, who had concealed a number of 

 small iron nails in his periwig, approached the machine and 

 viewed it closely from all sides, as though he were going to make 

 a critical examination of it. His true intention was, however, to 

 take away all electricity stored on the metallic balls, in which he 

 succeeded without touching the machine. 

 Imagine the horror of Father Francis when 

 he finally came to perform his experiment, 

 and found that, although his accumulators 

 were well insulated, all his electricity was 

 gone! 



In 1753 Prof. Richmann, of St. Peters- 

 burg, while observing a storm from a hut, 

 was killed by lightning descending an in- 

 sulated iron bar specially erected for the 

 purposes of the study. Upon learning of 

 the fate of that martyr of science, Divis 

 drew up a memoir on that unhappy occur- 

 rence, in which he demonstrated that the 

 iron bars, as used by Richmann, were both 

 unsafe and dangerous, and clearly showed 

 how, in case of a storm, the danger of a 

 lightning-stroke could be averted by means 

 of a conductor, the idea of which had al- 

 ready matured in his mind. This treatise 

 he sent to the famous mathematician and 

 naturalist, Euler, then President of the Ber- 

 lin Academy of Sciences, asking for his 

 judgment. But his application was in vain ; 

 the Academy failed to understand his rea- 

 soning. This is one of the numerous in- 

 stances which go to show that it is always 

 the individual workers to whom we have to look for any advance 

 in science rather than learned societies. When Franklin's ac- 

 count of his discovery was read in the British Royal Society, it 

 was laughed at by the connoisseurs. * 



Divis was not discouraged by the cold reception with which 



Fig. 1. — The Top of tb 

 Lightning-rod of Divis. 



