History of Natural Philosophy from the Earliest Periods to the Present Day

This historic book may have numerous typos and missing text. Purchasers can usually download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1834 edition. Excerpt: ... only to take that number which forms the tenth in the series. It is also evident, that these numhers of the terms are also the indices of the powers of the common multiplier, which enter into each term respectively. This is the leading idea which may be supposed suggested by a passage in Archimedes. Thus, if our computations always involved no other numbers than such as are terms in a geometrical progression, we should only have to add the indices, and thus be led directly to the product; or, conversely, to subtract them, and find the term which is the quotient. Again, by doubling, tripling, &c. the indices, we should find their products indicating a term which would be respectively the square, cube, &c.of the original term; and, conversely, we should have the square, cube, &c. roots. Thus far all was sufficiently clear and simple. But here arose the main difficulty: this would apply only to a very few limited systems of numbers, and could not be of any general practical utility. The grand discovery of Napier, therefore, amounted to this: --that a geometrical progression may be found in which All the natural numbers are terms. Of the methods by which he arrived at this conclusion, or of the general principle on which such a series can be assigned, we cannot here say much; but we may sufficiently illustrate it by an example. If we suppose a geometrical series whose first term is 10 and of notice; espetiaEt afterwards broachn., t, and have given i j tt ins.-ase;ira. Ti dud the relative places i mr-vmaia. wua ns be occupied by the nun It at ana or inaridiai, be adopted the so: i t Ta lunns iaenbmg two different lines. at vta nasaarc teiidtr. and die other with a re-ana.'s-imingn 31 due ratio of the...