They give to the water a sort of grayish-white appearance.

Then there is a fly, which looks something like our house fly.

These settle on the beach to eat the worms that wash ashore--and any time, you can see there a belt of flies an inch deep and six feet wide, and this belt extends clear around the lake--a belt of flies one hundred miles long.
If you throw a stone among them, they swarm up so thick that they look dense, like a cloud.

You can hold them under water as long as you please--they do not mind it--they are only proud of it.

When you let them go, they pop up to the surface as dry as a patent office report, and walk off as unconcernedly as if they had been educated especially with a view to affording instructive entertainment to man in that particular way.