My Lord,
Your Lordship’s
Most humble and most obedient Servant,
Daniel Peter Layard.
Huntingdon, 26 Nov. 1757.
LXX. _Trigonometry abridged. By the Rev._ Patrick Murdoch, _A. M.
F.R.S._
[Read Feb. 2, 1758.]
THE cases in trigonometry, that can properly be called different from
one another are no more than _four_; which may be resolved by _three_
general rules or theorems, expressed in the sines of arcs only; using
the supplemental triangle as there is occasion.
[Illustration: _Philos. Trans. Vol. L._ TAB. XX. _p. 539_.
_J. Mynde sc._]