C 170 ] 
XXV, Defer ip t ion of a new Method of ob- 
ferving the heavenly Bodies out of the 
Meridian : By J. Smeaton, F. R. S. 
Read May 16, y ■ ‘ 1 H E inftrument I propofe for this 
purpofe, is a tranfit telefcope, 
mounted on a vertical axis ; for example, fuch a one 
as is deferibed in the introduction to the Hijioire 
Celejle of Mr. le Monnier ; being one of the inflru- 
ments made by Mr. Graham for the academicians who 
went to meafure a degree at the Polar circle ; this or 
any other inflrument upon equivalent principles will 
Suffice, that is, capable of fuch adjustments, as to be 
made correctly to deferibe an almicanther and azimuth 
circle ; and capable of being retained in any given 
pofition : the ufe will appear by the following 
example. 
Make choice of any fixed ftar, which according to 
the diurnal motion, precedes the heavenly body to 
be obferved by a few minutes, more or lefs, as it may 
happen ; let the inflrument be fet to an azimuth, 
fomewhat preceding the fixed liar; and carefully 
obferve the time of the liar’s tranfit crofs the vertical 
wire of the telefcope; then wait till the heavenly body 
comes to the fame azimuth; and, when arrived within 
the field of view, keep gently turning the ferew that 
alters the elevation of the telefcope, fo as to follow 
the heavenly body in altitude ; keeping it interfered 
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