Fiddler-crabs inhabit various parts of the world, and are usually found in large numbers on muddy or sandy flats left dry by the tide, where they may be seen hurrying over the sand or peering out of their holes, into which they immediately vanish when alarmed. The holes, which usually are about a foot deep, are made by the crab persistently digging up and carrying away little masses of mud or sand. When he is doing this the crab presents a very funny appearance. Scraping up a quantity of sand into a little heap, he grasps it with three of the legs on one side and hurries away with it to some little distance. Having deposited his load, he raises his eyes, which he can do quite effectively, as they are situated at the end of very long, slender stalks, peers curiously around, and scuttles back to the hole for another load of sand.

How Far can a Powerful Searchlight Send Its Rays?

Searchlights have recently been made capable of being seen nearly a hundred miles away. Such lights are very valuable for signaling purposes in time of war, and they are also much used on warships, enabling the officers to detect the approach of an enemy in the dark and to guard against torpedo boats.

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Photo by Brown Bros.

Long Ribbons of Light

The giant scintillator erected on the shore of the bay was not the least wonderful of all the wonderful sights of the Panama-Pacific Exposition at San Francisco.

We are all familiar with the less powerful ones which are universally used on automobiles for night driving and in a multitude of other every-day practices. The illustration shows a battery of powerful searchlights, the use of which furnished some very effective displays during the Panama-Pacific Exposition at San Francisco in 1915.