2 examples of jump-off in sentences

From donkey to a ten-foot jump-off on the lake shore in a straight line on a five per cent.

Then a last big stick came with a rush, bunted these others powerfully so that they began to slide with the momentum thus imparted, slowly at first then, gathering way and speed, they shot down to the lake and plunged to the water over the ten-foot jump-off like a school of breaching whales.

2 examples of  jump-off  in sentences