Notices respecting New Booh. 205 



appear to have been the only authorities employed in laying down 

 those objects. But in the Philosophical Transactions for 1828 is a 

 catalogue of 629 nebulae and clusters of stars in the southern hemi- 

 sphere, observed at Paramatta by Mr. Dunlop, no use of which ap- 

 pears to have been made in the construction of these maps. 



Lacaille, we believe, observed only about 40 or 50 nebulae and 

 clusters oi stars in the southern hemisphere ; 26 of which, besides 

 the Nebula Major and Nebula Minor, are given. Now although a 

 large number of those described by Mr. Dunlop may be too small, 

 (like the remainder of Lacaille's,) to be laid down in the present 

 series of maps, and may require to be reserved for that which, as we 

 have mentioned, is now in preparation, yet it seems probable that 

 out of nearly 600 nebulae and clusters observed solely by Mr. Dunlop, 

 some must be equal in apparent magnitude to the 26 of Lacaille's 

 which have actually been inserted, and must therefore require inser- 

 tion in the present series equally with them. 



The " Planetary Nebulae" discovered by Struve, of which it is re- 

 marked in the " Explanation " that " they deserve to be reckoned 

 amongst the most interesting objects in the heavens," have with 

 great propriety been inserted j and No. 8 of Struve is the only one 

 of them which appears in the maps representing the southern hemi- 

 sphere. Now Nos. 266 and 267 of Dunlop probably belong to this 

 interesting class of bodies, especially the latter. 



Annexed to Mr. Dunlop's Catalogue are two elaborate plates, very 

 correctly laid down from observations, of the Nebula Major and Ne- 

 bula Minor, no use of which seems to have been made in representing 

 those nebulae in the maps. In Mr. Dunlop's plates their forms appear 

 to differ considerably from those given in the maps ; and the places 

 assigned to them by Mr. Dunlop, differ from those given by Lacaille. 

 In laying down the Milky-way, Mr. Dunlop's detailed map of it, from 

 the Robur Caroli to Scorpio, does not appear to have been referred 

 to. Lacaille is quoted in the "Explanation " as the only authority 

 respecting the dark space in the southern cross ; and this phaenome- 

 non, it is observed, " does not seem to have been attended to in any 

 celestial globes or maps." This also is particularly mentioned by 

 Mr. Dunlop, and is very accurately laid down by the telescope in his 

 map of the Milky-way. 



If we are correct in our estimation of the value of Mr. Dunlop's 

 observations, and if also the Society for the Diffusion of Useful 

 Knowledge should agree with us in the propriety of introducing such 

 of their results as come within the range of magnitude of the present 

 maps, in future impressions, probably, the omissions which we have 

 noticed will be supplied. [B.] 



XXXIX. Pro- 



