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C. A. Young—Observations of the Transit of Venus. 329 
Mr. McNeill’s observations were made with the 94-inch equa- 
torial, carrying the Grubb spectroscope. This bas a dispersive 
wer of from 2 to 10 prisms, variable at pleasure. During the 
observations 4 prisms were used for the most part (i. e. 2 prisms 
transmitting the light twice). Mr. McNeill saw the vapor lines 
between and near the D's, and thought he noticed a slight 
strengthening of both A and B, He did not observe any 
change in a, but a fine line just above C was intensified, and 
the line at 759-2 of Kirchofi’s scale (A=6392) appeared to be 
distinetly affected. 
At South Hadley Mr. West attempted observations with a 
grating spectroscope upon the 8-inch equatorial, but did not 
get any results; the image of the planet was too unsteady. 
The effects of the planet’s atmosphere upon the spectrum 
were certainly much less marked than I had expected ; but I 
think raver can be little doubt as to lines of aqueous vapor 
near D, 
VIIL Puorocrarnic WorRK. 
During the Transit a series of 191 photographs were taken 
Y Professor Brackett and his assistants, Professor Libbey and 
t. Magie. The apparatus was a horizontal photoheliograph 
of the same general plan and dimensions as those used by our 
Government parties. The plates and chemicals were furnished 
y the Transit of Venus Commission, which receives the pic- 
tures for measurement and discussion. 
_The wind and clouds interfered somewhat with the opera- 
tions, About 40 of the photographs are strictly first-class, and 
some 80 are worthless; the remainder are of all grades of 
excellence, from very good to very poor, but are probably all 
measurable. 
MISCELLANEOUS, 
The atmosphere of the planet was seen by all the observers 
at Princeton between the first and second contacts. No one, 
OWever, saw the peculiar enlargement of the rin of light 
noticed by Professor Langley at Allegheny, though did par- 
Heularly observe that the structure of the ring appeared to be 
tadiate and bristling, with scintillant knots here and there. 
No satellite was detected. No ring was seen on the sun’s dise 
surrounding the planet except such as would necessarily result 
m the imperfect eolor-correction of the object-glass. No 
Spots or markings were seen upon the planet’s dise, which at 
ingress appeared slightly but deidincsty darker than the back- 
ground on which it was projected. 
March, 1883. 
