222 Linncean Society, — Royal Astronomical Society. 



it, should try whether a large blaze of pyrotechnic composition 

 (the red light from strontian would perhaps answer well), or 

 the ordinary illumination of a lighthouse apparatus, be seen at 

 the greatest distance in a dense fog. 



It' it should prove that the blaze, by illuminating the clouds 

 or fog, possess any considerable advantage in such cases, it 

 would obviously be expedient to make occasional exhibitions 

 of such signals on lighthouses. 



I am, Gentlemen, very truly Yours, 



John Robison. 



XXXVII. Proceedings of Learned Societies. 



LINN-KAN SOCIETY. 



Jan. 15, and A PAPER was read on the Lycium of Dioscorides, 

 Feb. 5. -£*- by J. Forbes Royle, Esq., late Superintendant of 

 the Hon. East India Company's Botanic Garden at Seharampore. 



From the curious researches of the author, it appears that the sub- 

 stances known in the East under the names Hooziz, Rusot, and 

 Dar-huld, are the produce of a species of Barberry: and that the 

 words loofyon or lookyon are given by Arabic writers as the Greek 

 synonyms of Hooziz, followed by the description given by Diosco- 

 rides of Lycium, Avxiov, which is doubtless the word given by the 

 Arab writers as lookyon, or corruptly loofyon, their character for 

 yand Jc differing only by a diacritical point placed over the letter. 

 He therefore concludes this substance in the Materia Medica to be 

 the product of the wood or root of a species of Barberry. It is now 

 applied in cases of inflammation of the eyes. 



royal astronomical society. 



November 9, 1832. — The following communications were read : — 

 1. Observations of Biela's Comet, by Sir J. F. W. Herschel. 

 "The moon being sufficiently removed from the presumed place of 

 this interesting object, and the promising aspect of the evening of 

 the 22nd September last holding out hopes of detecting it by the 

 powerful light of the 20-feet reflector, I directed that instrument, with 

 a newly-polished mirror, to a point of the heavens determined by 

 taking a mean of the right ascensions and declinations, calculated by 

 M. Santini from his own and from Damoiseau's elements. A haze, 

 however, which, as the evening advanced, rapidly increased to a de- 

 cided cloud, disappointed my expectations for that night ; but on the 

 following evening, the sky being perfectly clear, after sweeping to 

 and fro for about five minutes over the place similarly calculated for 

 the time of observation, I had the satisfaction of seeing the comet 

 enter the field as a conspicuous nebula of about 2|' or 3' in diameter, 

 and of such a degree of brightness as would entitle it to a place in 

 my father's first class, or 'bright nebula?.' It had no tail; and though 



