heliograph

Here they donned rubber boots for collecting forays at low tide, devoured great dishes of spaghetti and watched swordfish “jumping in the afternoon light, flashing like heliographs in the distance.”

I wondered what the heliographs would look like in ordinary daylight.

The pioneers of reproductive imagery in the 1830s called their pictures by many names — heliographs, calotypes, daguerreotypes — but the word that stuck was photograph: a “drawing with light.”

Just think of the tectonic shifts it has undergone since the French inventors Nicéphore Niépce and Louis Daguerre were tinkering with heliographs and daguerreotypes.

As the big shells sped across the town to drop within the laager beyond, the enemy's signallers heliographed their direction to the emplacement of Big Ben.