130 Analysis of Scientific Books. 
15. An Account of the Effect of Mercurial Vapours on the Crew of 
His Majesty’s Ship Triumph, in the year 1810. By William 
Burnett, M.D., one of the Medical Commissioners of the Navy, 
formerly Physician and Inspector of Hospitals to the Mediter- 
ranean Fleet. Communicated by Matthew Baillie, M.D., F.R.S. 
The particulars of this curious case have been already published 
by Dr. Baird, in Nicholson’s Journal, for the month of Oct. 1810. 
16. On the Astronomical Refractions. By J. Ivory, A.M., F.R.S. 
This is a very long and laborious investigation of the problem 
of astronomical refraction; its result is a new table of refractions 
with which the paper concludes, and which is compared with other 
tables that have been long in the hands of astronomers, and the 
characters of which are well established. Mr. Ivory shews that it 
is fruitless to expect a near agreement in every single instance be- 
tween observation and any table of refractions whatever, and that 
there is no test of their accuracy except the smallness of the mean 
error in a series of observations made at different times. 
17. Observations on Air found in the Pleura, in a case of Pneumato- 
thorax ; with Experiments on the Absorption of different kinds of 
air introduced into the pleura, By John Davy, M.D., F.R.S. 
This is a medical history which Dr. Davy has endeavoured to 
illustrate by some experiments upon dogs. | He observes that the 
‘circumstances which he has ventured to bring forward are some= 
what favourable to the idea of the secretion or exhalation of azote, 
but are still far from conclusive. 
18. On Bitumen in Stones. By the Right Honourable George 
Knox, F.R.S. 
This is a second paper upon the same subject. Mr. Knox finds 
bitumen in every thing except rock crystal and pearl-white 
adularia. 
19. On certain Changes which appear to have taken place tn the 
Positions of some of the principal fixed Stars, By John Pond, 
Astronomer Royal, F.R.S. 
The Astronomer Royal thinks that his observations lead to the 
conclusion that some variation, either continued or periodical, 
takes place in the sidereal system, which producing but very small 
deviations in a finite portion of time, has hitherto escaped notice. 
The nature of this motion appears to be such that the stars are now 
mostly found a considerable quantity to the southward of their 
computed planes. With respect to the laws by which these 
motions are governed, the observations in question, he admits, are 
not sufficiently exact to throw any light upon them. , 
