V 
observations with the transit and mural circle. The observations of the comet 
of 1825 have already appeared in the Memoirs of the Astronomical Society, 
where its positions are given according to La Caille’s places of the compared 
stars. In the present work I have reduced them afresh by means of the places 
of these stars determined from my own observations, being desirous of giving 
here a complete view of the principal observations made at Paramatta. 
The determination of the right ascensions of some of the principal stars of 
the southern hemisphere by equal as well as by absolute altitudes, has been the 
most laborious part of my observations. I have omitted the particulars, which 
would have filled pages void of interest to those who are in possession of more 
perfect transit instruments, or have the means at hand of correcting their 
defects. I am, however, not without hopes that the few right ascensions 
given by me, and which are independent of one another, are free from those 
small constant errors that cannot easily be discovered in transit instruments. 
Next follow the south polar distances of the circumpolar stars deduced from 
their upper and lower culminations. Of these I have given the original obser- 
vations, in order to enable others to recompute them, to which they are in my 
opinion well entitled by their importance. The south polar distance of q Argus, 
(8 Crucis, and a Eridani, would probably be more correctly deduced from their 
upper culminations only, with the polar point derived from the other stars, 
whilst their lower culminations may serve to establish the law of refraction in 
the southern hemisphere. It would seem that the effects of the temperature and 
density of the atmosphere upon the refraction exceed the tabular corrections, 
which may be owing to a greater elasticity of the air in this warm climate. 
The conclusion makes a catalogue of the south polar distances of these stars 
with their constants of aberration and nutation. 
A future volume will contain a catalogue of the stars of the southern 
hemisphere, deduced from the observations with the transit and mural circle. 
