new Nebula and Clujlers of Stars . 467 
In every clafs the order of time when the nebulas and 
clutters of ftars were difcovered, or firft obferved with my 20- 
feet telefcope, has been followed ; and that I might defcribe all 
thefe objeCls in as fmall a compafs as could well be done, I 
have ufed Angle letters to exprefs whole words, an explanation 
of which, with an example of the manner of reading thofe 
letters, is given. It flhould be obferved, that all eftimations of 
brightnefs and fize mutt be referred to the inftrument with 
which the nebulae and clutters of ftars were feen ; the clear- 
nefs and tranfparency of the atmofphere, the degree of atten- 
tion, and many more particular circumftanccs, (hould alfo be 
taken into confideration ; fo that probably fome of the nebulae 
which I have called very bright, and very large, may only be 
juft perceivable, as very fmall faint patches, in many of our 
beft common telefcopes. 
The Identity of each nebula in this catalogue has been well 
afcertained by a projection on a proper map, made on purpofe, 
which pointed out all other nebulae near its place, and thus 
afforded the means of a rigorous examination. When, there- 
fore, feveral nebulae are found within the limits of the accu- 
racy with which my telefcope can difcriminate them, in dif- 
ferent nights, it may be concluded, that they were feen either 
at once in the fame field of view, or otherwife in immediate 
fucceffion during the fame fweep. 
In the fame manner thefe nebulae have been compared with 
thofe that are contained in the two volumes of the Connoijfance 
des c Temps, > for the years 1783 and 1784, of which none have 
been inferted in this catalogue. It was indeed eafy enough to 
diftinguifh the nebulae of that excellent colleClion from thofe 
of mine which in feveral places are very near them : The 
quantity of good light in my telefcope having enabled me, 
Vol. LXXVI. P p p even 
