374 Analijsis of Scientific Books. 



the length of which was found =6.0063609 inches, and the 

 diameter of the sphere thence deduced gave 113.5264 inches 

 for its solid contents. 



Captain Kater concludes this paper with a table, shewing the 

 data furnished by Sir G. S. Evelyn's experiments, and his own 

 measurements, from which it appears that the weight of a cubic 

 inch of distilled water, in a vacuum, at 62°, is =252.888 grs. 

 of Sir George's standard, or 252.722 grains of the parliamen- 

 tary standard. 



11. An account of Observations made with the Eight-feet Astrono- 

 mical Circle, at the Observatory of Trinity- College, Dublin, 

 since the beginning of the year 1818 ,for investigating the effects 

 of the Parallax and Aberration on the places of certain Fixed 

 Stars ; also the comparison of these with former observations 

 for determining the effects of Lunar Nutation. By the Rev. 

 John Brinkley, D.D., F.R.S. &c. 



The observations, of which an account is given in this com- 

 munication, were instituted with a view to discover the source of 

 the differences that have existed between the observations 

 made at Greenwich and those at Dublin, relative to parallax. 

 After a perspicuous and detailed statement of the method of 

 conducting his observations. Dr. Brinkley avows his inability 

 to rectify the discordancies, observing, at the same time, that, 

 as the whole extent of the difference in question is but one 

 second, it may by some be considered as showing the great 

 precision of modern observations. Yet, independent of the 

 interest of the question of parallax, it is important that the 

 origin of the difference, small as it is, should be ascertained. 



12. On the Effects produced on the Rates of Chronometers by the 

 Proximity of Masses of Iro7i. i>y Peter Barlow, Esq., of 

 the Royal Military Academy. 



In a paper printed in the Philosophical Transactions for 1820, 

 Mr. George Fisher, wlio accompanied Captain Buchan to the 

 Arctic regions in 1818, has shewn that the rates of chronome- 

 ters differ on board and on shore, gaining in the former, and 

 losing in the latter situation ; this he attributed to the magne- 

 tic influence of the ship's iron on the balance, and instituted va- 

 rious experiments, which with their results are detailed in his 

 communication, to shew that the magnetic influence lias a ten- 

 dency to accelerate the motion of the time-keepers by its in- 

 fluence on the steel part of their balances. Mr. Barlow's in- 

 quiries contained in the paper before us have led him to different 

 conclusions ; he found, as might be expected, that the proximity 

 of masses of iron influences the rates of chronometers, but so 



