Rivers’ face paled suddenly, and involuntarily he bore so heavily on the bit that his horse reared high.  Taken unawares, his usually facile mind was confused by the abruptness of Richard’s words and the calm determination plainly foreshadowed in them.  Trained by years of experience in a Court where intrigue imbrued the very atmosphere, ordinarily he was equal to any emergency.  But all his schemes of the past were as gossamer to the conspiracy in which he was now entangled, and since the previous evening—­when the unexpected arrival of Gloucester had hung their whole plot upon his shoulders until he got the King to London—­the strain on his nerves had been terrific.  He had thought to play the game out in the Capital, not on the lonely bank of a river in distant Northampton; and it is small wonder that under all the circumstances Anthony Woodville fell before Richard Plantagenet, whose equal England had known but twice before, in the first Plantagenet and the first Edward, and knew but twice thereafter, in Oliver Cromwell and William of Orange.

“This is scarce a place for discussion, my Lord Duke,” said Rivers, striving to calm his restive horse.  “If, as your words imply, there be aught of controversy between us, it were best to settle it in London.  Yonder is Stoney Stratford, and it will not profit the King for us to quarrel here.”

“Methinks, Sir Earl, that I am quite as capable as you of judging what shall work to Edward’s profit,” replied Gloucester curtly; “and I choose to settle it here, and not to annoy him with matters too weighty for his young brain.”

“It is your own profit and not your King’s that you seek,” said Rivers.  “I decline to hold further discussion or to quarrel with you until I have done my duty to my Sovereign and have seen him safe in London.  Then I shall be most willing to meet you, with sword, or axe, or lance—­and may God defend the right.  Come, Grey, we will ride on alone.”

Gloucester had listened with darkening brow, and the gnawing of under lip was ominous; but at the last words he threw his horse in front of the Earl’s.

“Ere you depart, my Lord of Scales and Rivers,” he said, and smiled peculiarly, “you must hear me out.  Of your rash speech I shall make no account; and you know full well that a Prince of England breaks no lance nor crosses sword save on the field of battle, whereon are all men equal.  But I fain would ask if you expect to meet Edward the Fifth in yonder town?”

“I have already told you that I dispatched a messenger to detain him until we arrived,” retorted the Earl hotly.

“Aye!  And later another messenger to hurry him on,” said Richard laconically.

“What proof have you for that?” demanded Rivers, reining back.

“This!” replied the Duke sternly, producing the captured letter.

“I see nothing but a bit of parchment; yet well I know that it can be made to tell strange tales for selfish ends.”