heliograph

An apparatus for signalling by means of a moveable mirror which reflects flashes of sunlight.

Now Jones had left his new-wed bride to keep his house in order, / And hied away to the Hurrum Hills above the Afghan border, / To sit on a rock with a heliograph; but ere he left he taught / His wife the working of the Code that sets the miles at naught. / And Love had made him very sage, as Nature made her fair; / So Cupid and Apollo linked, per heliograph, the pair.

It was a lieutenant and a couple of privates of the 8th Hussars, with a stand like a theodolite, which the artilleryman told me was a heliograph.

A heliogram.

An instrument for measuring the intensity of sunlight.

A device for photographing the sun.

A photograph.

To send a message by heliograph.

With damnatory dot and dash he heliographed his wife / Some interesting details of the General's private life.

To send a heliograph.

To photograph by sunlight.