Page:The Construction of the Wonderful Canon of Logarithms.djvu/20

xvi INTRODUCTION. generally believed to have been Napier’s friend, Dr Craig. The computation of the Table or Canon, and the preparation of the two works explanatory of it, the Constructio and Descriptio, must, however, have occupied years. The Canon, with the description of its nature and use, made its appearance in 1614. The method of its construction, though written several years before the Descriptio, was not published till 1619.

Napier at the same time devised several mechanical aids to computation, a description of which he published in 1617, ‘for the sake of those who may prefer to work with the natural numbers,’ the most important of these aids being named Rabdologia, or calculation by means of small rods, familiarly called ‘Napier’s bones,’

The invention of logarithms was welcomed by the greatest mathematicians, as giving once for all the long-desired relief from the labour of calculation, and by none more than by Henry Briggs, who thenceforth devoted his life to their computation and improvement. He twice visited Napier at Merchiston, in 1615 and 1616, and was preparing again to visit him in 1617, when he was stopped by the death of the inventor. The strain involved in the computation and perfecting of the Canon had been too great, and Napier did not long survive its completion, his death occurring on the 4th of April 1617. He was buried near the parish church of St Cuthbert’s, outside the West Port of Edinburgh.

It has been stated that Napier dissipated his means