Lomaland Photo. and Engraving Dept.
THE CANAL, TROLLHÄTTAN, SWEDEN
Lomaland Photo. and Engraving Dept.
HIGH SLUICE AND PALACE OF INDUSTRY, AMSTERDAM, HOLLAND
(At Amsterdam a stone arch bridge is called a sluice)
Lomaland Photo. and Engraving Dept.
PALACE OF INDUSTRY, AMSTERDAM
And yet there are some eyes which can plainly distinguish the fact that a substance or surface is giving off these powerful rays, invisible to less sensitive eyes. Perhaps this is one of the thousands of little forerunner facts which testify to the increase of sensibility prophesied by H. P. Blavatsky for this present century.
Now if a solution of one per cent of sulphate of quinine, one centimeter thick, is used in a glass cell before a lens or plate it may delay the exposure by perhaps six times the normal time, thus showing that of our photographs taken under ordinary conditions on ordinary plates we have been accustomed to accepting as true pictures reproductions of the invisible, although much of that invisible coincides with the visible, since these rays are emitted by so many substances.