The Account , See. 
433 
the great triangles, with their variations ; and we have, with 
as much brevity as possible, inserted a narrative of each year’s 
operations. This will be found, however, to extend only to 
the First Part, or that containing the particulars of the survey 
in which the great instrument alone was used. The remain- 
ing contents of this portion of the work, are necessarily con- 
fined to the angles of the principal, and secondary triangles, 
with the calculations of their sides, in feet ; and likewise such 
data as have no connection with the computations of latitudes 
and longitudes. 
Part the Second contains an account of a survey carried on 
in Kent, in the years 17 95 and 1 796, with the small instru- 
ment, by order of the Master General, for completing a map 
of the eastern and southern parts of that county, for the use 
of the Board of Ordnance, and the military commanders on 
the coast. 
In Part the First will be found an article, for which we are 
indebted to Dr. Maskelyne, the Astronomer Royal. It con- 
tains his demonstration of M. de Lambre’s formula, in the 
Connoissance des Temps of 1793, for reducing a distance on the 
sphere to any great circle near it, or the contrary. The prac- 
tical rule thence derived, for reducing the angles in the plane 
of the horizon, to those formed by the chords,, is very useful, 
and will considerably abridge the trouble which must neces- 
sarily arise in computing the chord corrections by any former 
method. 
