The bond of union was still further strengthened by the fact that, while the comparatively learned Miles was enthusiastic and communicative, the unlettered Armstrong was inquisitive and receptive, fond of prying into the nature of things, and always ready as well as competent to discuss-- not merely to _argue_.  Observe the distinction, good reader. Discussion means the shaking of any subject into its component parts with a desire to understand it.  Argument has come very much to signify the enravelment of any subject with a view to the confusion and conquest of an opponent.  Both young men abhorred the latter and liked the former.  Hence much of their harmony and friendship.