664 Chronicles of Science. [ Oct., 
the nebulous matter having receded so as to leave open the southern 
end of the lemniscate vacuity. Mr. Abbot first published the fact 
that 4 is no longer in the dense portion of the nebula where it was 
seen by Sir John Herschel. 
In 1857 the Astronomer-Royal made a communication to the As- 
tronomical Society on the means available for correcting the received 
measure of the sun’s distance from the earth. Among the different 
subjects of observation applicable within some years to this object, he 
particularly indicated the transit of Venus, December 6, 1882, treated 
by the method of comparison of duration of transits at different places, 
as one meriting most careful consideration. The Society has lately 
been favoured by the learned professor with a further communication 
on this transit, illustrated with orthographic projections of the illu- 
minated sides of the earth for ingress and egress. From these it is 
seen that on the seaboard of the Unitéd States of America, the dura- 
tion of transit would be shortest. The possible maximum of shortening 
being 2°U0,,that at the United States is represented by 1:78. The 
Southern States, as far as the Gulf of Mexico, would be almost as 
favourable, and would have the advantage of a higher sun at egress. 
Bermuda would be also a very good place, the whole shortening there 
being 1:8. The circumstances therefore are exceedingly favourable 
for the selection of observing stations at which the duration of transit 
will bemuch shortened. The choice of stations where the duration of 
transit will be longest is more limited, and the practical difficulties 
rather greater. The most favourable position that can be found is 
between Sabrina Land and Repulse Bay, where the lengthening of the 
transit would be represented by 1:61—a very large amount; the 
geometrical possible maximum being 2:00. This point near Sabrina 
Land being the only one very suitable for the observation, the Astro- 
nomer-Royal thinks it very desirable that a reconnaissance should be 
made of different points on the Antarctic continent, and that it should 
not be long deferred. The first locality to be examined is that in 7” E. 
longitude between Sabrina Land and Repulse Bay, the points to be 
ascertained being Ist, whether the coast is accessible on the 6th of 
December ; 2nd, whether a latitude of 65° can be reached; and 8rd, 
whether the sun can usually be seen well on December 6th at 2° and 8" 
Greenwich mean solar time. Should the answer to the first or third 
of these questions be negative, then it would be proper to examine 
other portions of the south continent, say in longitude not very different 
from 5" west, but with no particular restrictions except that of gaining 
the highest possible south latitude. And the only point for inquiry 
would be, how well the sun can usually be seen on December 6th at the 
hours above named. 
Referring to an adverse criticism which Messrs. Stone and Carpenter 
made upon Professor Bond’s drawing of the nebula of Orion, in which 
these gentlemen considered it was not so accurate as that of Sir John 
Herschel, Professor Bond has communicated to the Astronomical 
Society a detailed defence of his own drawing, and a notice of that of 
Sir J. Herschel. He appears to show very satisfactorily that Messrs. 
Stone and Carpenter have not been altogether warranted in their 
