330 Mr. Sweat on’s Obfervaticn of Mercury 
Col. 4, of this table contains the corre< 5 lions of the- 
times deduced from the journeyman clock (as per col. 3.) 
to reduce it to mean time; which corrections are made 
out from the general account of the goings of the tranfit 
clock, corrected by tranfits of the fun, taken the. 2zd, 23d, 
27th, and 30th of September, 2nd the 12th, 13th., and 14th 
of O&ober *. The journeyman deck was regularly com- 
pared at nights and mornings with the tranfit clock ; and ge- 
nerally immediately after the obfervation. The meridian and 
rotative obfervatories in which the clocks refpeCtively were, 
are at the diftance of 53 yards E. and. W. ; the comparifons 
were made by a feconds flop watch 4-. 
The numbers of the fourth column being properly applied 
to thofe of the third produce the fifth ; and which, with the 
fixth column, will be fufficientLy explained by their titles. The 
parts of the micrometer in the feyenth column, being reduced 
into minutes and feconds, are contained in col. 8. and reflec- 
tively fhew the minutes and feconds at which each objeT 
pafled to the north or fouth of the center of the telefcope. 
The value of the parts of the micrometer were obtained by 
previous obfervations, from whence the following rule was 
deduced : the numbers of turns and centefimal parts being con- 
iidered as integral, and divided by 1.08, the quotient will be 
the number of feconds. Thus,, in the obfervation of 0 Tauri 
* The tranfit clock was made by Hindley, and has a pendulum rod of 
etdar wood. 
t The journeyman clock was generally fet to the tranfit clock on Sunday 
mornings; and when from home the former was fuffered to go down. The 
journeyman will generally agree with the tranfit clock to 1" in 24 hours; but during 
the period of thefe obfervations, went remarkably well. 
upon 
