G98 -AN ACCOUNT OF THE 
uncasiness in the position, and it is well known how essential‘an easy position 
is to correct operations of every kind. In using points too far laying off the 
length of the rod, it was evident, that a little uncertainty would prevail. 
The great length would have made it also unwieldy, and where the position 
of one of the points was necessarily to depend on the intelligence, and care of 
a native, it was feared that much accuracy could not be expected. This 
idea was therefore abandoned, but I have thought proper to notice it here, 
not only to shew the difficulties. I had to contend with, but also as thinking. 
it might be found useful on other occasions, where only 2 tolerable degree 
of correctness may be desirable, 
“4. Axrnovan I saw the inconvenience of points, acting as I was 
without a coadjutor, yet [ did not immediately give up the pickets; indeed 
the objections and difficulties that mterfered with any plan depending on. 
stands, were strong motives te do if possible without them. I therefore: 
considered, if the method by pickets might not be so far modified as to be 
executed by contacts instead of points. I recollected the apparatus which _ 
the Freneh philosophers had employed on a similar occasion, where they 
had used metallic rods, placed in a line, but not im actuai contact, the shock of 
the latter being supposed likely to cause considerable errors, ‘To determine 
the distances of the rods or rulers, there were smal] slips of metal sliding: in 
grooves called by them Langueties, and furnished with verniers, by means of 
which they could determine the exact quantity between the rods to the 
greatest nicety: such an apparatus I saw was applicable to wooden rods, 
supported on pickets, placed nearly but mot quite in contact. {n this 
way the position would be much easier, and the accuracy of the work 
