a 388 PROCEEDINGS ‘OF THE SECTIONS. 
sae observation. I also think that the observations are less 
_ liable to error from what a be termed the accidental 
irregu- 
larities on the moon’s surface, the contact is more likely to be — 
oheerved when the thread is sntina lay tangential to the average 
ce; whereas the star at an occultation may happen to 
disappear behind the top of a lunar mountain or at the he 
‘of a valley; this certainly could produce but a ve 
but should be considered when the number of observations of this 
kind is limited. 
r C is an extract from the Rabin Greenwich corrections 
A. 
_ of the moon’s R. 
An inspection of this paper shows that there exists @ con- 
siderable amount of uncertainty as to what correction should 
th a mauktde I have not as yet been able to procure t 
‘corrections of the R.A. from Washington or any other Observ- 
‘tories to combine with the Greenwich values. In the event of 
my obtaining them in a short time, I will with your permission 
_take an opportunity of making an addition to these papers in the 
shape of a small table showing the xeonilie as deduced from such 
data. 
For many years henee there will be instances in which the 
requirements for settlement as well as important scientific cies 
: gations, such as the transit of Venus, &c., aes 
determination of longitude e by lunar observations "either wid ree 
Aas sscthod of oocaltatio tions, culminations, 0 
:e) 
A 
similar process 
of 
as practised at sea, and paket epee 
sesleaaiacs still be useful for that” 
