r 
[ Vi ] 
XIX. On the optical and physical properties of Tahasheer. By 
David Brewster, LL. D. F. R. S. Lond. and Edin. In a 
Letter to the Right Hon. Sir Joseph Banks, Bart. G. C. B. 
P. R. S. &c. &c. &c. p. 283 
XX. An Account of a Membrane in the Eye, now first described. 
By Arthur Jacob, M. D. Member of the Royal College of 
Surgeons, Ireland; Demonstrator of Anatomy, and Lecturer on 
the Diseases of the Eye in the University of Dublin. Commu- 
nicated by James Macartney, M. D. F. R. S. p. 300 
XXL A new method of solving numerical equations of all orders, 
by continuous approximation. By W. G. Horner, Esq. Com- 
municated by Davies Gilbert, Esq. F. R. S. p. 308 
