94 (TRANSIT OF VENUS). PROF. WILLIAMSON: REPORT OF 
Transit of Venus, Dec. 6th, 1882.—Report of Observations at Kingston Observatory. 
By Pror. Wiuitamson, LL.D. 
(Abstract.) 
We had so far the advantage in preparing for the “ Transit ” here that the longitude of 
the site of the former Observatory building had been previously determined by every known 
method, continued for anumber of years, as well as by telegraphic communications to 
be 5" 5% 54°. 6 W., with a probable error of not more than #, of a second. 
Its latitude had been no less carefully ascertained by a series of observations near zenith 
stars—particularly B.A.C., 4841, 5400, 6013, and 6731,—by transit with attached micrometer 
in the prime-vertical to be 44° 13’ 21”. 7 N. 
The site of the new observatory building in which observations began to be taken last 

year is on higher ground, and a little further to the west, and the necessary triangulation 
being made, the longitude and latitude of the equatorial pier, from which the transit was 
viewed, were found to be 5" 5" 56°. 4 W., and 44 13’ 25". 2 N., respectively. 
The instruments in the observatory are the “ Beaufoy Transit,” lent by the Royal 
Astronomical Society, and a small portable transit by Simms, both in excellent order. In 
the tower at the west end of the building is the equatorial by Alvan Clark. 
There are also mean time, and sidereal clocks, with excellent escapements and com- 
pensation pendulums constructed by Professor Dupuis. 
The instruments usually employed are the large Beaufoy transit, and the equatorial, 
and those were made use of in connection with the transit of Venus. 
The Beaufoy transit has an object glass of three inches clear aperture, and 50 inches 
focus. 
The equatorial has a 64 inch object glass, of 8 feet focus, and at the end next the eye 
was fitted with a solar reflecting prism, and neutral tint glasss wedge. The eye-piece em- 
ployed in viewing the transit, was a positive one, with a power of a hundred and twenty, 
which was found to give the sharpest and best defined vision of the limbs of the sun and 
planets. Besides the clocks already referred to, two other time keepers were available, and 
the times of contact as given by these on the day of the transit were alone employed. 
The one was a half-second M.T. chronometer, number 2382, by Parkinson and Frod- 
sham, lent by the British Admiralty for the use of Canadian observers, and the other a very 
perfect M.T. clock in Professor Dupuis’ house, with compensation pendulum and Denison’s 
gravity eseapement, and electrically connected with a chronograph there and with the 
observatory. 
Both the clock and chronograph are of Professor Dupuis’ construction, the rate of the 
clock being very steady. 
On the evening of the 5th of December, clock signals were received from Toronto, 
and also on the evening of the 16th. 
The difference between the means at Toronto and Kingston from the result of the 
signal exchanges is 11" 37° 7. Hach second for four minutes of Kingston mean time was 
also on the evening of the 6th signalled to Toronto. Special observations were made for the 
