Paper, 'Experiments in heliotropism' by George John Romanes

Description

Romanes writes: 'I cannot find in the literature of heliotropism that any experiments have hitherto been made on the effects of interrupted illumination, when the periods of illumination are rendered as brief as possible— i. e., instantaneous flashes of light. Accordingly I have conducted an extensive research on heliotropism, where the flashes have been caused either by means of electric sparks in a dark room, or by the, opening, of a photographic shutter placed before the plants in a camera obscura with an arc light or Swan burner, at a distance of several feet on the other side of the shutter. The electric sparks were made either with a Wimshurst machine, induction sparks, or by means of the following contrivance.'

Annotations in pencil and ink. Marked on front as 'Not quite complete.'

Subject: Botany

Received 2 October 1893 / 3 November 1893. Read 16 November 1893.

A version of this paper was published in volume 54 of the Proceedings of the Royal Society as 'Experiments in heliotropism'.

Reference number

PP/22/23

Earliest possible date

1893

Physical description

Ink and graphite pencil on paper

Page extent

4 pages

Format

Manuscript