460 Mr. Fallows's catalogue of southern stars. 
rate of the clock by the transits of stars near the zenith, as 
the azimuthal error would hardly be felt when the axis was 
correctly levelled. The rates thus obtained were propor- 
tioned to the intervals between the high and low Greenwich 
stars, and the error of position easily found ; afterwards, the 
observed transits of other stars were corrected to the meri- 
dian according to their respective altitudes or declinations, by 
a method well known to all practical astronomers. 
By uniting the results of several pairs of Greenwich stars 
taken in the same night, the error of position is more correctly 
found. 
For example. Nov. 19, 1822. 
East. 
c o%705 by Fomalhaut and a. Androm. 
The azimuthal error = < o ,804 Fomalhaut and a. Arietis. 
*0 ,711 Sirius and Capella. 
Mean 0,74 East. 
Nov. 26, 1822. 
East. 
ro s ,o5 by Fomalhaut and a Androm. 
The azimuthal error = < o ,47 Fomalhaut and a. Arietis. 
*0 ,54 Sirius and Capella. 
“ The mean of the two last (viz. o*,5o) was preferred, as 
the lamp had only been lit a short time before the observa- 
tion of a. Andromedse, and the level was found deranged.” 
Having briefly pointed out the plan by which the right 
ascensions in the following Catalogue were obtained, I shall 
now put down a few observations of two bright stars, as spe- 
cimens of the rest, corrected for the error of the instrument. 
