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was in close proximity to the umbra was so great that the last contact was 
difficult to observe.” Mr. Penrose found, however, that even simultaneous 
unaided eye-observations of the beginning and end of totality did not differ 
by many seconds. 
Opposition of Ariadne. — The minor planet Ariadne (43) is in opposition on 
July 24, in circumstances very favourable for determining its diurnal 
parallax by the heliocentric method. The distance of the planet from the 
earth is 0*83, the sun’s mean distance from the earth being taken as unity. 
Mr. Gill proposes to observe this planet with the heliometer during his stay 
at Ascension, where the observations will be made under very favourable 
conditions. Opposition will occur ten days before he can begin to observe 
Mars satisfactorily. The observations can therefore be made without 
inconvenience or additional expense. “It is true,” says Mr. Gill, “the 
planet is somewhat faint (8-8 mag.), but experience at Mauritius has taught 
me that with such a heliometer as Lord Lindsay’s, in a tropical sky, 
8 -5 mag. stars can be measured with more accuracy than any other, and 
that ninth mag. stars can be well measured in favourable atmospheric con- 
ditions. The geometrical conditions are very much more favourable than in 
the case of Juno (whose distance at opposition was 1*05) ; and besides it is 
possible to select more suitable stars of comparison . . . The opposition of 
Iris (7) and Melpomene (18) are also very favourable.” 
The Planet Vulcan. — It is hardly necessary to say that the transit of 
Vulcan, expected by Leverrier on March 22 (or 21 or 23), was not observed 
either in the northern or the southern hemisphere. 
The Great Meteor of March 17 last. — Captain Tupman has collected 
together various observations of this meteor, as seen at Frome, Cambridge, 
Kensington, Gunnersbury, Tetbury, Bossall, and Brighton. From these he 
has deduced the following inferences : — 
The, radiant must have been very near B.A. 145°, N.P.D. 95°, at an alti- 
tude of 35°. The meteor first became visible 60 miles over 50° 59' N., 
3° 4' W. (or nearly over Taunton). The point of disappearance was about 
39 miles above 5° 41' N., 3° 4' W. (near Pontypool). This path satisfies all 
the descriptions within ordinary errors of observation. The length of the 
path was about 59 statute miles. The duration was given as certainly about 
3s., by Mr. Homer ; 4s. or 5s., by Mr. Hollis ; 3s., by Mr. Ballard, at Ban- 
bury ; and 2s., by another observer. The mean of these is 3*ls., giving a 
relative velocity of 19 miles per second. From the radiant point given 
above the following parabolic elements of the orbit are deduced : — 
Bising node . . . . 
. 177-4 
Inclination .... 
8-5 
Longitude of perihelion . 
. 222-5 
Perihelion distance 
. 0850 
Motion 
. . Direct. 
Whence the relative velocity is 33*3 statute miles per second, and the total 
duration seconds. It follows, then (though Captain Tupman makes no 
reference to the point), that, if the duration was rightly observed, the real 
path of the meteor was hyperbolic. 
During the first half of its track the meteor was like burning magnesium 
