The Collaborative International Dictionary of English v.0.48:
Photogen \Pho"to*gen\, n. [Photo- + -gen.] (Chem.)
A light hydrocarbon oil resembling kerosene. It is obtained
by distilling coal, paraffin, etc., and is used as a
lubricant, illuminant, etc. [Written also photogene.]
[1913 Webster]
The Collaborative International Dictionary of English v.0.48:
Photogene \Pho"to*gene\, n. [See Photogen.]
1. A photograph. [Obsoles.]
[1913 Webster]
2. A more or less continued impression or image on the
retina. --H. Spencer.
[1913 Webster]