27S Heport of the Astronomical Society. 



bers of this Societv, in the very infancy of its existence : and for 

 which, this Society is bound to retain a due and grateful remem- 

 brance. 



At the close of the last session, the Council received a com- 

 munication from Captain Basil Hall, expressing his readiness to 

 attend to anv instructions on subjects wherein he might be of 

 service to the science of Astronomy, in his intended voyage to the 

 South Seas. They availed themselves of the offer of this intel- 

 ligent and cnterprizing officer, and requested his attention to the 

 following principal points. 



To observe, as frequently as possible, the conjunctions of the 

 moon and planets with the fixed stars ; measuring with a micro- 

 meter their differences of right ascension and declination, or ta- 

 king the measure of their distance in a straight line: the time 

 and place of observation being correctly noted. 



To look out for occultations of the fixed stars by the moon ; 

 and particularly for those which may be presumed to be of short 

 duration, with a view to the illustration of the theory of Cagnoli 

 respecting this mode of determining the figure of the earth. And 

 it was remarked to him that, as the moon was now, and would 

 be for some few years, in such a position with respect to her nodes 

 as to pass over the Pleiades every lunation, it would be particu- 

 larly desirable to look out for the occultations of those stars. 



To make frequent sweeps of the heavens, with a telescope 

 having a larj^e field ot view and small magnifying power, for the 

 purpose of discovering anv comets ; and to note the progress and 

 circumstances of the same; making sketches of their appearance. 

 The Council at that time were not in possession of the calculated 

 place of the comet which is expected to return in 1822. But, 

 having since received an ephemeris of its apparent positions, com- 

 puted by M. Eucke, they will endeavour to forward it to Captain 

 Hall, and request him to look out for the same: a circumstance 

 the more to be desired, since it is expected to assume a different 

 appearance in the Southern hemisphere to that which it will pre- 

 sent in Europe. 



It appeared unnecessary to remind Captain Hall of the several 

 eclipses of the sun and moon, together with the eclipses of Jupi- 

 ter's satellites, the transit of Mercury over the sun's disc on No- 

 vember 4, 1822, and the several ph?enomena noted in the various 

 ephemerides ; and which would of course be the object of his 

 attention without any particular suggestions from this Society. 

 But the Council took the liberty of directing his attention to cer- 

 tain points, should he be favourably situated for observing any of 

 the solar eclipses, or the transit of Mercury. 



They also requested him to make observations on the position 

 of Mars, at the time of his opposition in February 1822, with 



respect 



