19^ Proceedings of the Royal Society of Edinburgh. 
Kennedy presented this worm to the Society. It was found’ 
by Captain Thomas Brown to be a new species of the ascaris, 
to which he gave the name of Ascaris pellucidus. In a letter, 
dated Madras 7th July 1818, which Dr Kennedy has subse- 
quently received from Dr Moore, who was present at the ope- 
ration, and with which he has kindly favoured us, is the follow- 
ing paragraph : I received the worm, with the aqueous hu- 
mour of the eye, in a cup, and it continued to move with great 
vivacity for some time, until I added a little water, when it in- 
stantly fell dead to the bottom of the cup.” 
Nov. 23. — paper by Dr Brewster was read on the Action 
of Crystallized surfaces upon light. This paper was divided in- 
to two sections : 
Sect. 1 . — On the effects produced upon transmitted light by a 
change in the mechanical condition of the surfaces of crystals. 
In this section a method was pointed out and explained, by 
which either of the images of doubly refracting crystals, could 
be rendered nebulous or extinguished at pleasure. 
Sect. II. — On the influence of the polarising force of doubly 
refracting crystals upon the polarising force which accom*^ 
panics partial reflection. 
Under this section, the author treated 
1. Of the change produced upon the polarising angle by the 
interior forces of doubly I’efracting crystals. 
2. On the change produced upon the direction of the pola- 
risation of the reflected ray by these interior forces ; and 
. S. On the general results deduced from his experiments. 
Nov. 30. — At a general meeting of the Society, the follow- 
ing gentlemen were elected office-bearers for 1819 : 
Sir James Hall, Baronet, President. 
Vice Presidents. 
Right Honourable Lord Gray, 
Lord Glenlee, 
Professor Playfair, Secretary. James Bonar, Esq. Treasurer. 
Thomas Allan, Esq. Keeper of the Museum and Library. 
PHYSICAL CLASS. 
Sir G. S. Mackenzie, Bart. President. Dr Thomas Charles Hope, Secretary. 
Counsellors from the Physical Class. 
Colonel Imrie. Mr James Jardine. 
Professor Jameson. Honourable Captain Napier. 
Dr Brewster. Dr A, Duncan juw’or.. 
