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more extraordinary manifestations: the sun appeared to have no
beams, which at sunset on an average cloudy day can be magni-
ficent. Further, as Ascroft put it,
William Ascroft, three
sketches from
Twilight
and Chromatic Afterglow,
Chelsea
, November
1883-6, pastels,
reproduced litho-
graphically, 1888.
the light was so sickly that clouds opposite the sun had
none of that richness of colour which is usually seen at,
or just after, sunset. In the daytime the lights on clouds
under the sun were frequently of a greenish-white hue.
So it went on, and until April 1886, Ascroft continued to
record the phenomenon. He noticed what came to be called
'Bishop's Rings', distinct bluish or brown circles around the
sun caused by volcanic dust in the atmosphere, and what Ascroft
described as 'blood afterglows' and 'amber afterglows'. By July
1888, when the drawings were exhibited as a group of more
than 530 at the South Kensington Museum (the original name
of the Victoria and Albert Museum), the artist recorded that the
afterglows 'are still occasionally seen, though much modified'.9
This was five years after the eruption. We should observe a note
of caution, because although with 'few exceptions the sketches
were done directly from Nature', Ascroft admits that some of the
drawings were done from memory. They were, however, con-
sidered to be of such interest that selections were exhibited at
conversazioni of the Royal Society.¹0 When the drawings came
to be printed for the Krakatoa Committee of the Royal Society
Ascroft insisted that the printers worked only in bright weather
to avoid the errors that he considered had been made in printing
colour reproductions of Turner's paintings.¹¹
Some 320 km (200 miles) northwest of Chelsea, at Stony-
hurst College, Lancashire, another especially literate observer, the
poet Gerard Manley Hopkins, looked carefully at the autumn
and winter skies in 1883. He collected evidence from scientists
around the world, and also wrote to the editor of the journal
Nature
about what he himself had seen:
The glow is intense, this is what strikes everyone; it has
prolonged the daylight, and optically changed the season;
