420 PHILOSOPHICAL TRANSACTIONS. [anNO 1753. 



Severus. And perhaps no time was more open for such licentious practices, as 

 might justly merit the name insolentia, than the loose reign of Commodus ; 

 who though he was not the immediate predecessor of Severus, yet died but a few 

 months before he came to the empire. Besides, we have two other inscriptions 

 found in Britain, addressed Numinibus Augustorum ; both which are thought to 

 relate to Severus and his elder son Caracalla, after he was joined with his father in 

 the government. Nor can there be any doubt of this, as to one of them at least ; 

 which is an altar, and has on one side of it the names of both his sons, Caracalla 

 and Geta, as consuls that year. So that on the whole. Dr. W. can find no other 

 period of time so probable for fixing the date of this inscription. 



LII. On some Electrical Experiments, made at Paris. By Mr. Benjamin 



Wilson, F.R.S. p. 347. 



Mr. W. being at Paris, M. Mazeas informed him that Dr. le Monnier, some 

 months ago, h:id read a paper at a meeting of the Royal Acad, of Sciences, in 

 which he told them, that he had great reason to believe the electric matter did 

 not come from the earth at all, but from the air. On Mr. W. mentioning this 

 to the Doctor, he found him still of the same opinion. As there was a conveni- 

 ent apparatus in his apartment, Mr. W. proposed making the experiments : for he 

 always thought that the electric matter came from both, but principally from the 

 earth ; and that probably a difference of 10 to 1 would be perceived, on making 

 the experiments. 



The machine was suspended by silk lines in such a manner, that every part of 

 it was not less than '2 feet distant from any non-electric. The lines were dried 

 by a chafing-dish of fire made with charcoal, as was also the glass globe ; and 

 every other precaution was strictly observed, that seemed necessary for making 

 the experiments. 



The doctor appeared to be well versed in electrical inquiries, and showed great 

 judgment in conducting the whole. He got upon the suspended apparatus him- 

 self, and rubbed the globe with both his hands ; while another person, who was 

 likewise suspended, turned the wheel of the machine. Close to the globe was a 

 slender slip of lead ; at one end of which was fastened some brass tinsel, to serve as 

 a collector of the electric matter. The other end of the lead had a communication 

 with a tin tube, which was supported by silk lines about a foot in length : and as 

 this tube hung higher than could be reached, another was hooked to it by means 

 of a wire which hung down to a convenient distance. 



As Mr. W. stood on the floor, he took hold of this last tube, while the glass 

 was rubbed, that the apparatus, and the persons on it, might lose as much of 

 their natural electricity as possible under such circumstances. On removing his 



