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SCIENTIFIC SUMMARY. 
ASTRONOMY. 
n iHE Approaching Transit of Venus. — We describe elsewhere the plans 
which have now been adopted for observing the approaching transit 
of Venus. It is satisfactory to note that the part which England is to take 
is far worthier of her position in the scientific world than that originally 
proposed for her. Instead of five stations, she will now occupy no less than 
nine. Instead of applying only Delisle’s method, she will apply not only 
both Halley’s and Delisle’s methods, but the photographic and the direct 
methods. The concessions which have been made, in fact, by the officials 
at our Natiomxl Observatory are ample in themselves, and honourable to 
those who had acquired, by long tradition, what might almost be termed a 
vested interest in inflexibility of demeanour. It is a point of small impor- 
tance that the change of plan has been effected silentty, and as it were 
surreptitiously. So long as Halley’s method is to be applied we can 
readily overlook the vague manner in which its advantages have been 
spoken of. Now that the value of the once overlooked North Indian 
region is fully recognised, we need not count the steps by which a plan for 
applying photography only at Delhi gradually became metamorphosed into 
a decision to apply all the available methods at Peshawur, the very course 
pointed out by Mr. Proctor in 1869. One modification only of this kind 
requires to be here noticed. It is commonly stated that there are to be 
two English stations at Kerguelen Land, and.it is in this manner that the 
Greenwich statement just published presents the matter. It should be 
known, however, that the head of the Kerguelen party has instructions to 
put one of the parties on Macdonald, or Heard Island, if possible ; in other 
words, another concession has been made by Greenwich in secret. Sir 
George Airy u does good by stealth.” 
The American and European Methods of Photographing the Transit . — 
Some attention has recently been directed to the question of the relative 
advantages presented by the two methods of photographing the transit of 
Venus adopted respectively by the American and by the European 
observers. The managers of the American scheme of observations consider 
that the method which has so long been adopted at Kew, however excellent 
for securing beautiful sun-pictures, is not trustworthy enough for recording 
so delicate a phenomenon as the transit of Venus. In the Kew method 
the focal image is optically enlarged, and although the amount of enlarge- 
ment — that is, the scale of the sun-pictures — is theoretically calculable, 
VOL. XIII. XO. LI I. X 
