TKA^"SIT OF TEXr?. 95 



themselves to a course of previous practice at the Observatory 

 which involved an amount of self-denial and perseverance worthy 

 of all praise. From the officers also of the Eailway and Telegraph 

 Departments we received very great assistance ; indeed, every one 

 seemed to make common cause for once with the astronomers, 

 and did all in their power for the Transit of Venus. 



Previous to starting, all the observatories and instruments were 

 set up in Sydney, and each party went to work in their own 

 observatory ; this we found to be of great service in pointing out 

 weak points, which required either more practice or the instru- 

 ment maker to set right. 



For practice in observing, we had two artificial transits, one 

 similar to that designed by the Astronomer Royal, the other con- 

 structed in the Colony. With this a great deal of practice was 

 obtained, which was useful in training for observation. At the 

 same time all were warned that there was no certainty about the 

 black drop phenomena. 



We come now to the day's work, and take first the weather 

 at each station. 



At Eden the morning was fine and very promising, but about 

 11 a.m. clouds began to come in from the sea, with a fresh 

 sea breeze, and the observers began to anticipate a disappoint- 

 ment. Fortunately up to the time of ingress the clouds had not 

 interfered with the observations ; but from that time forward the 

 sun was more or less obscured, and at one period wholly so for 

 80 minutes, so that few photographs could be obtained, and the 

 sun was entirely obscured some time before egress. 



At Goulburn the morning was fine, with light westerly wind 

 and a few drifting clouds ; during the afternoon the wind increased 

 to half a gale, and the clouds were more numerous, but not 

 sufiicient to interfere with observation. 



At Woodford the morning was fine, with a dry hot wind 

 (westerly), which increased as the day wore on; during the 

 afternoon a few clouds passed over and interrupted the photo- 

 graphic work for a short time, but at ingress and egress the 

 weather was splendid for observation. 



At Sydney the early morning was beautifully clear until 

 5'30 a.m., when a heavy bank of fog came in from the sea, and 

 obscured the sun for three hours ; but we still expected a fine 

 day, and were not disappointed, for by 9 a.m. we had a clear 

 bright sky and light north-easterly wind, which increased to a fresh 

 sea breeze during the afternoon. The state of the atmosphere 

 also was favourable for observation until the transit was over, 

 except a few moments of bad definition ; but had we been one 

 hour later, I do not think observations of egress would have been 

 worth anything, for clouds were rapidly forming in the S.W., 

 and, though thin, they spread very quickly over the sky. 



