Robert Perceval Graves ‎

“ For many years Graves and Hamilton maintained an active correspondence, in which they vied with each other in endeavours to carry into space a full and coherent interpretation of imaginaries. Graves worked as having for his aim the perfecting of algebraic language; Hamilton had persistently in view the higher object of arriving at the meaning of the science and its operations. These conjoint labours bore their great fruit in 1843, when Hamilton discovered quaternions, and it was to Graves that he made on 17 Oct. ”

“ In his preface to the ‘Lectures on Quaternions’ and in a ‘prefatory letter’ to a communication to the ‘Philosophical Magazine’ for December 1844 will be found ample acknowledgments of his indebtedness to his friend for stimulus and suggestion. Graves modestly disclaimed the credit of suggestion, and continued to be a sympathetic companion of the great mathematician in all his future work. ”

“ In his twentieth year (1826) he engaged in researches respecting exponential functions, which conducted him to important results. They were printed in the ‘Philosophical Transactions’ for 1829 under the title ‘An Attempt to Rectify the Inaccuracy of some Logarithmic Formulæ.’ Of these results one of the principal is the discovery of the existence of two arbitrary and independent integers in the complete expression of an imaginary logarithm. ”