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A conductor appears with a flash lamp and lights their way.

Invented in 1960, lasers use an external "pump," such as a flash lamp, to excite electrons within the atoms of a lasing material—usually a gas, crystal, or semiconductor.

"You're not French," he said several times as the curious Americans gathered about him in a close, dim circle illuminated by pocket flash lamps.

Bart, as a precaution, however, had brought along a pocket electric flash lamp, to use when they reached the case of live reptiles.

Glad to be of help to his father, Bert arose from the ground, to which he had slipped when the sudden noise of the owl startled him, and went to hold the flash lamp.