The Church avenges itself on those who betray its secrets, senor.' 'As one day its secrets will avenge themselves upon the Church,' I answered bitterly.

'And now let me seek a fitting drug--one that is swift, yet not too swift, lest your hounds should see themselves baffled of the prey before all their devilry is done.

Here is something that will do the work,' and I held up a phial that I drew from a case of such medicines.

'Come, veil yourself, mother, and let us be gone upon this "errand of mercy."' She obeyed, and presently we left the house and walked away swiftly through the crowded streets till we came to the ancient part of the city along the river's edge.

Here the woman led me to a wharf where a boat was in waiting for her.