a. ? Obs. [f. LOGARITHM, on the analogy of ARITHMETICAL.] = LOGARITHMIC.
1621. W. Jameson (title), Account of John Neper’s Logarithmetical Triginometriae (in 2nd Rep. Hist. MSS. Comm., 201).
1685. J. Hawkins, Cocker’s Decimal Arith., II. i. 205. Logarithmetical Arithmetick is an Artificial use of numbers, invented for ease in Calculation.
1690. Leybourn, Curs. Math., 191. Logarithmetical or Proportional Scales.
1824. New Monthly Mag., XI. 416. Ye who learn logarithmetical rules at Cambridge.
Hence Logarithmetically adv.
1775. in Ash.
c. 1850. Rudim. Navig. (Weale), 144. The sliding rule is … graduated logarithmetically.
