Direct Chemical
- Chemoluminescence (Lightsticks)
- Fluorescence
- Phosphorescence
Read more about this topic: Light Sources
Famous quotes containing the words direct and/or chemical:
“Long as I have lived, and many blasphemers as I have heard and seen, I have never yet heard or witnessed any direct and conscious blasphemy or irreverence; but of indirect and habitual, enough. Where is the man who is guilty of direct and personal insolence to Him that made him?”
—Henry David Thoreau (1817–1862)
“We do not want actions, but men; not a chemical drop of water, but rain; the spirit that sheds and showers actions, countless, endless actions.”
—Ralph Waldo Emerson (1803–1882)