undulating

The air and water were shining in the beams of the morning sun; on the shore the sailors were sitting, chatting and laughing; and at ten yards from them the boat was at anchor, undulating gracefully on the water.

Thus every now and then he saw in fancy amid the sailors, seated on a rock, or undulating in the vessel, one of the shadows which had shared his dream with looks and kisses.

“It is a wonderful place, the moor,” said he, looking round over the undulating downs, long green rollers, with crests of jagged granite foaming up into fantastic surges.