On the crest running eastward we suddenly witnessed a strange meteorological and optical phenomenon.

You need several physics ideas to really appreciate this optical phenomenon-solet's get to it.

Any term of optics; any optical phenomenon.

An optical phenomenon of a remarkable kind was witnessed when the voyagers had attained their highest point.

No, I am not the sport of any hallucination, and this is no case of an optical phenomenon.

While we were climbing over the broken lavas of the Malpays, we perceived a very curious optical phenomenon, which lasted eight minutes.

On a side note, Zimmer mentions a fascinating optical phenomenon: When receptors in the eye get overstimulated by a certain color, they become less sensitive.

As if the "Golden West" seen by Poets were no longer a mere optical phenomenon, but growing a reality, and coining itself into solid blessings!

Upon reflection, I find that the other dog and the meat are only optical phenomena.

This very curious optical phenomena has been investigated by Mr. Talbot and by Mr. Warrington.

Talking about optical phenomena, we had a curious one yesterday evening which was pointed out to me by Hyson.