FRANCIS HAUKSBEE. 457 



nosity with certainty in the vial; and stranger still, that 

 when the vial contained air, the light appeared like sparks 

 "which arise simultaneously and perish almost at the 

 same time;" but when the vial was exhausted of air "the 

 light is like a continuous flame which lasts incessantly 

 while the quicksilver is in agitation. " The least hu- 

 midity, even the perspiration of the hand, would put the 

 light out. 



Bernouilli's discovery was hailed in Germany with en- 

 thusiasm. It was supposed that he had invented a new 

 mode of mechanical illumination which might perhaps 

 render candles and lamps things of the past. And he 

 probably so believed himself, for he seems then to have 

 had no conception of the real cause of the glow. 



Before long the news reached the Royal Society. 

 Hooke was then incapacitated for arduous work by both 

 age and illness, and Francis Hauksbee, 1 who held the office 

 of curator of experiments, undertook to investigate the 

 matter. Little is known concerning Hauksbee further 

 than that he had already achieved reputation as an experi- 

 mentalist. His first recorded researches bear date 1705, 

 and he seems to have been a persistent student until he 

 died, some seven years later. That he was a man of un- 

 usual genius in original research is abundantly shown. 

 His mind was^ philosophical, and but little influenced by 

 the prevalent hypotheses which to many seemed axiomatic. 

 To him is due not merely the recognition of the effect of 

 Newton's reduction of electric phenomena under general 

 law, but the almost instant perception that the next log- 

 ical step was the seeking of "the Nature and Laws of 

 Electrical Attractions" which u have not yet been much 

 considered by any." He invented a form of air-pump that 

 is still known by his name; but his fame ought to rest, 

 and deservedly, upon his extraordinary electrical experi- 

 ments now to be recounted. 





Hauksbee: Physico Mechanical Experiments on Various Subjects. 

 London, 1709. See also his communications to the Royal Society in 

 years 1705 to 1712 inclusive. 





