Presidential Address. 
427 
a telescope, such a reversal as I have imagined can be comparatively 
easily secured. 
A device to obtain this end was attached to the instrument and utilised 
throughout the observations of 1911, and all observations were made by 
means of an equal number of transits in each direction, right to left and 
left to right. Nearly two hundred comparisons were made between pairs 
of observers, each of the two observers observing the same star at the 
same transit over different parts of the telescope field. A discussion of 
these comparisons has yielded the following results for the apparent 
personal discordances between the different observers. In order to make 
the results strictly comparable with those previously exhibited they have 
been reduced to the equator." 
Personal Discordances for Circumj^olar Stars. 
A a cos 0 
s. 
C. - -0-001 
A.P. = -0-004 
E.G. - -0-012 
A.W. = +0-011 
M. = +0-006 
J.J. = -0-007 
S. -= +0-008 
It will be seen at once that the outstanding discordances are of a 
scarcely detectable character, and that practically we may consider the 
problem of the elimination of personal errors to have been solved. 
The discussion of the observations made with the new Transit Circle, 
since it was first brought into use, which is now in progress in connection 
with the formation of a catalogue of results, has yielded several results of 
interest. For instance, I should like to have given some analysis of the 
performance of that essential accessory to every transit circle, viz., its 
clock, and to have exhibited figures indicative of the general stability of 
the instrument. The time at my disposal has, however, compelled me to 
restrict this address to-night to the one aspect of meridian observing, viz. : 
the elimination of the personal errors of Eight Ascension observations. 
