550 



Intelligence and Miscellaneous Articles. 



" On the Theory of Elliptic Motion." By Arthur Cayley, Esq., 

 F.R.S. 



On the Application of Electrical Discharges from the Induction 



Coil to the purposes of Illummation.' 

 F.R.S. 



The subjoined figure represents a carbonic- 

 acid vacuum tube of about ^ of an inch inter- 

 nal diameter, wound in the form of a flattened 

 spiral. The wider ends of the tube, in which 

 the platinum wires are sealed, are 2 inches in 

 length and about ^ an inch in diameter, and 

 are shown by the dotted lines ; they are enclosed 

 in a wooden case (indicated by the surrounding 

 entire line), so as to permit only the spiral to be 

 exposed. 



When the discharge from a Ruhmkorff's in- 

 duction apparatus is passed through the vacuum- 

 tube, the spiral becomes intensely luminous, ex- 

 hibiting a brilliant white light. Mr. Gassiot, 

 who exhibited the experiment at the meeting 

 of the Society, caused the discharge from the 

 induction coil to pass through two miles of cop- 

 per wire ; with the same coil excited so as to 

 give a spark through air of one inch in length, 

 he ascertained that the luminosity in the spiral 

 was not reduced when the discharge passed 

 through 14 miles of No. 32 copper wire. 



By J. P. Gassiot, Esq., 



LXXV. Intelligence and Miscellaneous Articles. 



ON THE ALLEGED PRACTICE OF ARSENIC-EATING IN STYRIA. 

 BY DR. H. E. ROSCOE. 



Professor Roscoe being anxious to obtain further definite informa- 

 tion respecting the extraordinary statements of Von Tschudi, quoted 

 by Johnston in his ' Chemistry of Common Life,' that persons in 

 Styria are in the habit of regularly taking doses of arsenious acid, 

 varying in quantity from 2 to 5 grains daily, was supplied, through 

 the kindness of his friend Professor Pebal of Lemberg, with a series 

 of letters written by seventeen medical men of Styria to the govern- 

 ment medical inspector at Gratz, concerning the alleged practice. 

 After reviewing the opinions of Dr. Taylor, Mr. Kesteven, and Mr. 

 Heisch upon the subject, and having mentioned the results and 

 conclusions arrived at by those who had previously interested them- 

 selves with the subject, Mr. Roscoe stated that all the letters received 

 from the medical men in Styria agree in acknowledging the general 

 prevalence of a belief that certain persons are in the habit of conti- 



