j Thefe compares I thought the belt that could be procured
yet when applied to the meridian line, I found them to
dtflrer not only one from another, fometimes a degree and an
half, but the fame needle, half a degree from iffelf in difth
ltT h H ° n thC fame day 5 and 1 do not remember
hat I have ever found two needles which exactly agreed at
the fame time and place, though I have often found tie fame
needie agree with itfelf, in feveral trials made one after the
other. This imperfedion o f the needle, however, is of no
confequence to navigation, as the variation can always be
found to a degree of accuracy, more than fufficient for all
nautical purpofes.
C H A P .
