18Q2.] Philosophical Tran$actims for 1821, Part II, U^ 



der, Q.rid Sphere, used hi/ the late Sir George Shuckburgh Eveli/n, 

 in his Inquiries respecting a Standard of Weights and Measures. 

 By Capt. Henr}^ Kater, FRS. / 



The experiments above referred to are detailed in the PhilosOr 

 phical Transactions for 1798 ; and "it may there be seen/' says 

 Capt. K. " that a cube, a cylinder, and a sphere of brass, were 

 employed^ the respective dimensions of which being given, as 

 well as the weight of water displaced by each, the weight of a 

 cubic inch of distilled water might thence be readily ascertained. 



'* In reviewing these experiments, so much care appears to 

 have been bestowed on those parts of the inquiry which relate 

 to weighty as to leave no reason to doubt their accuracy ; but as 

 Sir George Shuckburgh has not entered into so full a detail of 

 the method he pursued in the measurement of the cube, the 

 cylinder, and the sphere, I felt it to be desirable that this opera- 

 tion should be repeated before the Commissioners of Weights 

 and Measures should make their final Report." 



Sir George's experiments were repeated by Captain Kater, 

 and the paper concludes by collecting under one view the data 

 furnished by Sir George Shuckburgh's experiments and his own 

 measurements, and he observes, that " From these data, the 

 weight of a cubic inch of distilled water in a vacuum at 62°, 

 deduced from the cube, appears to be 



252-907 of Sir G. Shuckburgh's grains. 



From the cylinder 252-851 



From the sphere 252 907 



The mean of which is . . 252-838 



which is equal to 252-722 grains of the Parhamentary Standard.'^ 



XXIV. An Account of' Observations made with the Eight 

 Feet Astronomical Circle, at the Observatory of Trinity College, 

 Dublin^ since the Beginning of the Year 1818, ybr investigating 

 the Effects of Parallax and Aberration on the Places of certain 

 Fixed Stars ; also the Comparison of these with former Observa- 

 tions for determining the Effects of Lunar Nutation. By the 

 Rev. John Brinkley, DD. FRS. and MRIA. Andrews Professor 

 of Astronomy in the University of Dubhn. 



Respecting this very elaborate paper, we can scarcely say any 

 more than state the purposes for which the experiments detailed 

 in it were undertaken, which are thus mentioned by Dr. B. 



" The results of the observations which I now beg leave to 

 lay before the Royal Society, were instituted with a view of dis- 

 covering, if possible, the source of the differences that has 

 existed between the results of former observations made here, 

 and of others made at the Royal Observatory at Greenwich; and 

 they vv^ill, it is imagined, be found to be useful relative to some 

 other important points in astronomy. 



'* My former observations of certain stars pointed out a devia- 

 tion of about one second from the mean place, after having made 



