Igritta dove off the jetty into the river, her bare feet not making so much as a squeak before she splashed water everywhere. Then she swam up through the centre of her float, and that's when the runes started glowing orange. Presumably, they'd been etched to activate upon contact.
Cali was not so brave, though. She had one foot in hers while the other remained firmly on the jetty. Yes, Cali wanted to see what would happen, but the desire was not born of desperation. Still, Igritta seemed okay when she called out. 'Is this barrier magic? I recognise the glow from the tall ships you all helped us destroy on Tristren.'