They had no sooner drunk, however, than the draught, working with subtle power, suddenly kindled in their hearts a passionate love, destined to last as long as they both lived.
"Now that the maiden and the man, Fair Iseult and Tristan, Both drank the drink, upon them pressed What gives the world such sore unrest,-- Love, skilled in sly and prowling arts,-- And swiftly crept in both their hearts; So, ere of him they were aware, Stood his victorious banners there.
He drew them both into his power; One and single were they that hour That two and twofold were before." GOTTFRIED VON STRASSBURG (Bayard Taylor's tr.).
After the first few hours of rapture had passed, the young people, who honorably intended to keep their word and conquer the fatal passion which had overwhelmed them, remained apart, and when Iseult landed in Cornwall her marriage was celebrated with Mark.

Brangwaine, who knew all that had passed, tried to shield her mistress in every way, and blind the king, who is depicted as a very unheroic monarch, but little fitted to secure the affections of the proud young Iseult.
[Sidenote: Tristan and Iseult.] This story of a love potion whose magic power none could resist, and of the undying love which it kindled in the unsuspecting hearts of Tristan and Iseult, has been treated in many ways by the different poets and prose writers who have handled it.

In many of the older versions we have lengthy descriptions of stolen interviews, hairbreadth escapes, and tests of love, truth, and fidelity without number.
In many respects the story is a parallel of that of Lancelot and Guinevere, although it contains some incidents which are duplicated in the "Nibelungenlied" only.

But throughout, the writers all aver that, owing to the magic draught, the lovers, however good their intentions, could not long exist without seeing each other.
By means of this boundless love Tristan is said to have had an intuitive knowledge of Iseult's peril, for he hastened to rescue her from danger whenever events took a turn which might prove fatal to her.

There are in some of these old romances pretty descriptions of scenery and of the signals used by the lovers to communicate with each other when forced by adverse circumstances to remain apart.