VOL. XLIII.J PHILOSOPHICAL TRANSACTIONS. 127 



off. Its external surface was opaque, very uneven, of the colour of dry earth ; 

 but the inner surface, viewed in the same manner, appeared a confused heap of 

 very short and thin small masses, or small purple atoms, connected by inter- 

 spersed variegated threads, chiefly of a whitish colour ; but at the edge there ap- 

 peared red prickles ; and the whole contexture seemed like that which in the ani- 

 mal economy anatomists describe in the fat ; where they say this oil is lodged in 

 cells, which cohere with that lanuginous soft cellular substance. 



From these, and several other microscopical observations, M. G. concludes, 

 that the bark must be more efficacious than the whole root, especially when we 

 consider that the purging principle of vegetables resides chiefly in their resinous 

 parts. 



Remarks on the Operation of Cutting for the Stone. By Claud. Nic. Le Cat, 

 M.D., F.R.S. Translated /rom the French by T. S., M.D., F.R.S. N" 

 476, p. 391. 



These remarks have been published in a separate tract, to which the surgical 

 reader is accordingly referred. They form an entire pamphlet, and would be 

 very improperly retained in a collection (such as the present.) of short disserta- 

 tions or memoirs. 



Extraordinary Electrical Phenomena. By M. De Bozes, Professor of Experi- 

 mental Philosophy at the Academy of ffirtemberg. N° 476, p. 419. 



A hollow globe of glass, of 6 or 8 inches diameter, being swiftly turned round 

 on its axis, by means of a large wheel, in the manner Mr. Haukesbee formerly 

 advised ; and being rendered as electrical as possible by the application of a dry 

 woollen cloth, or rather of a very dry hand ; if, while in this swift rotation, it 

 be brought near the end of an iron bar, suspended by silken strings exceedingly 

 well dried, such an electric power will be communicated to the iron, that on 

 touching the other end of it with a finger, not only sparks of fire, in the usual 

 manner, will be emitted very briskly, but even blood will be drawn from the 

 finger; the skin of which will be burst, and a wound appear as if made by a caustic. 



1. If highly rectified spirit of wine heated in a spoon, the ethereal spirit of 

 Frobenius, oil of turpentine, sulphur, pitch, or resin melted, be applied to the 

 iron bar, instead of the finger, the sparks proceeding from it will set it on fire 

 instantly. 



3. A chair being suspended by silken ropes made perfectly dry, a man placed 

 in it is rendered so much electrical by the motion of the globe, that in the dark 

 a continual radiance, or corona of light, appears encircling his head, in the 

 manner that saints are painted. 



4. When several such globes, or electric tubes, are brought neai* the man 



