 Preston's early inclination for diplomacy was symptomatic of his character, which Fuller has summed as that of 'a perfect politician' apt 'to flutter most on that place which was furthest from his eggs'.He had 'great self-command, kept his own counsel, and was impervious to outside criticism'.Only to Ball does he seem to have frankly bared his mind, and Ball's admiring delineation of him furnishes a singular picture of cautious astuteness and constitutional reserve.