The highest point of a wave is the crest. The lowest point is the trough. The vertical distance between a crest and a trough is the height of the wave. Wave height is also called amplitude. The horizontal distance between two crests is the wavelength. Both amplitude and wavelength are measures of wave size. The size of an ocean wave depends on how fast, over how great a distance, and how long the wind blows. The greater each of these factors is, the bigger a wave will be. Some of the biggest waves occur with hurricanes. A hurricane is a storm that forms over the ocean. Its winds may blow more than 150 miles per hour! The winds also travel over long distances and may last for many days.

Other factors being equal, why would an ocean wave be larger if the wind were blowing 150 miles per hour than if it the wind were blowing 100 miles per hour?

When a stream or river slows down, it starts dropping its sediments. Larger sediments are dropped in steep areas. Some smaller sediments can still be carried by a slow moving stream or river. Smaller sediments are dropped as the slope becomes less steep. Alluvial Fans In arid regions, a mountain stream may flow onto flatter land. The stream comes to a stop rapidly. The deposits form an alluvial fan. Deposition also occurs when a stream or river empties into a large body of still water. In this case, a delta forms. A delta is shaped like a triangle. It spreads out into the body of water.

Where do larger sediments get dropped when a river or stream slows down?

We waited for half an hour, watching the smoke curling over the house, and then, judging that the Indians had made off for fear of being ambushed, we crossed the clearing. It took but a glance to read the story. The women had been washing by the little brook before the cabin, with the children playing about them, when the Indians had come up and with a single volley killed them all except the child we had heard crying. They had swooped down upon their victims, torn the scalps from their heads, looted the house, and set fire to it. We dragged out the body of the woman which had been thrown within, in the hope that a spark of life might yet remain, but she was quite dead. Beneath the warrior Spiltdorph had shot we found the child. It was a boy of some six or seven years, and so covered with blood that it seemed it must be dead. But we stripped it and washed it in the brook, and found no wounds upon it except in the head, where it had been struck with a hatchet before its scalp had been stripped off. The cold water brought it back to life and it began to cry again, whereat Spiltdorph took off his coat and wrapped it tenderly about it.
Who died in the attack?