124 A SOUTHERN OBSERVATORY. 
us by the varying time configurations of its parts. But as yet our 
knowledge of stellar movements is miserably scanty. They are appar- 
ently so minute as to become perceptible, in general, only through ob- 
servations of great precision extending over a number of years. Even 
the quickest-moving star would spend two hundred and fifty-seven years 
in crossing an are of the heavens equal to the dise of the full moon. 
Yet all the time (owing to the inconceivable distances of the objects in 
motion) these almost evanescent displacements represent velocities in 
many cases so enormous as to baffle every attempt to account for them. 
“Runaway stars” are no longer of extreme rarity. One in the Great 
Bear, known as “ Groombridge, 1830,” invisible to the naked eye, but 
sweeping over at least 200 miles each second, long led the van of stellar 
speed. Prof. Pritchard’s photograpic determination of the parallax of 
p Cassiopeiz shows, however, that inconspicuous object not only to be 
a sun about forty times as luminous as our own, but to be traveling at 
the prodigious rate of 300 miles (while Dr. Elkin’s result for Arcturus 
gives it a velocity of little less than 400 miles) a second! 
The “express” star of the southern hemisphere, so far, is one of the 
fourth magnitude situated in Toucan. Its speed of about 200 miles a 
second may however soon turn out to be surpassed by some of the 
rapidly-moving stars picked out for measurement at the Cape. Among 
them are some pairs “drifting” together, and presumed therefore to be 
connected by a special physical bond, and to lie at nearly the same dis- 
tance from ourselves. This presumption will now be brought to the 
test. 
A remarkable and typical change has affected the aims pursued at 
our southern national observatory since Dr. Gill assumed its direction. 
There has been a widening of purpose matching the widened scope of 
astronomical science due to the development of new methods. The 
practical usefulness of the establishment was never more conspicuous 
than at present. The shipping interests, railway service, and survey- 
ing operations of South Africa are in immediate dependence upon it. 
The whole fabric of the “old astronomy ”—so far as one hemisphere is 
concerned—is held together by the re-determinations of “ fundamental” 
and “ standard ” stars continually in progress at it. But while noth- 
ing of what was previously held in view has been relinquished, much 
of incalculable value has been added. Above all, the ideal, or purely 
intellectual, side of astronomy has obtained recognition, and in a form 
likely to be memorable in the history of the science. 
The celestial-photographic Paris Congress of April, 1887, might be 
called ‘‘ epoch making,” for this reason alone—that it marked, officially 
and forever, investigations into the structure of the sidereal universe 
as part of the proper duty of astronomers. These inquiries, the most 
sublime of the physical kind with which the mind of man can be occu- 
pied, will not henceforth be abandoned to individual caprice, to be 
prosecuted by necessarily inadequate means, and neglected when those 
means (as they could not fail to do) should collapse under the strain 
