[The phrase 'green radiance' occurs in An Evening Walk, ll. 264-8, first published in 1793, and reprinted in 1820. In 1836 the lines were omitted.
Oft has she taught them on her lap to play
Delighted with the glow-worm's harmless ray,
Toss'd light from hand to hand; while on the ground
Small circles of green radiance gleam around.]
[98:1] The Holmes, in the Bristol Channel.
[99:1] Light from plants. In Sweden a very curious phenomenon has been observed on certain flowers, by M. Haggern, lecturer in natural history. One evening he perceived a faint flash of light repeatedly dart from a marigold. Surprised at such an uncommon appearance, he resolved to examine it with attention; and, to be assured it was no deception of the eye, he placed a man near him, with orders to make a signal at the moment when he observed the light. They both saw it constantly at the same moment.
The light was most brilliant on marigolds of an orange or flame colour; but scarcely visible on pale ones. The flash was frequently seen on the same flower two or three times in quick succession; but more commonly at intervals of several minutes; and when several flowers in the same place emitted their light together, it could be observed at a considerable distance.
This phenomenon was remarked in the months of July and August at sun-set, and for half an hour when the atmosphere was clear; but after a rainy day, or when the air was loaded with vapours nothing of it was seen.
The following flowers emitted flashes, more or less vivid, in this order:—
| 1. The marigold, galendula [sic] officinalis. |
| 2. Monk's-hood, tropaelum [sic] majus. |
| 3. The orange-lily, lilium bulbiferum. |
| 4. The Indian pink, tagetes patula et erecta. |
From the rapidity of the flash, and other circumstances, it may be conjectured that there is something of electricity in this phenomenon. Notes to Poems, 1796. Note 13, pp. 186, 188.
In 1797 the above was printed as a footnote on pp. 93, 94. In 1803 the last stanza, lines 91-96, was omitted, and, of course, the note disappeared. In 1828, 1829, and 1834 the last stanza was replaced but the note was not reprinted.