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Logarithmologia or the whole doctrine of logarithms, common and logistical, in theory and practice. In three parts / [Benjamin Martin].

  • Benjamin Martin
Date:
1740
Catalogue details

Licence: Public Domain Mark

Credit: Logarithmologia or the whole doctrine of logarithms, common and logistical, in theory and practice. In three parts / [Benjamin Martin]. Source: Wellcome Collection.

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    four Terms of the Logarithmical Series becomes un¬ avoidable *, whereas if o be the firft Term, three other Terms only fuffice in the Multiplication of any two Proportionals whatever: for the Sum of their Logarithms will point out the Product^ and fhew its Place^ that is, its Difiance from, or Ratio to, the firft Terni of that Scale of Proportionals, But if the firfi Lerm in the Scale of Logarithms were fignificant, it muft be fubdudled from the Sum of the Mean, in order to find the Producft of the two Proportionals^ ific, as before; and fo we ftiould per¬ petually have double Labour in every Operation. All this is evident from the different Series of Loga¬ rithms in the foregoing Table. 16. This being the Nature, and fuch the won¬ derful Properties of thofe Numbers called Loga¬ rithms, ’tis natural to fuppofe that he who firft dif- cover’d them, would m.ake fuch a noble Difcovery as fubfervient as poffible to the Ufes of Life, for the genera! Benefit of Mankind, but more immediately of Artifis or Mathematicians,_ 17. Now to do this,’twas Proport. Logarith. j neceffary to calculate and fit “ ~ o^ooooooo 2. Scale or Canon of Loga- _ liooooooo rith'ms to all Numbers which 10012 *0000000 Men commonly make ufe of 3.0000000 in Bufmefs, that fo the Fa- 4.0000000 //g-ue and Labour of Multi- 100000 5.0000000 flyings Dividing, See. large 1000000 6.0000000 iiums or Numbers might be- avoided by only the Addition or Subftradlion, ffic, of Logarithms. And of confequence nothing lefs than a general Lable of Logarithms for all Numbers between Unity, or i and looooooor 100000005 could fuffice *, becaufe no Number muft here be wanting, as in the other intermitting Series i, 2, 4, 8, 16, ffic, fince general Ufe requires them all, and therefore tj)eir Logarithms. Proport. Logarith. ] I 10 100 1000 10000 100000 1000000 0.0000000 1.0000000 2.0000000 3.0000000 4.0000000 5.0000000 6.0000000 18.