from The Century Dictionary and Cyclopedia
- Same as concavo-concave.
Sorry, no etymologies found.
The thick, double-concave lenses indicated a degree of myopia that must have bordered on total blindness without glasses, and acute tunnel vision, even with them.
By these it is seen that a double-convex lens tends to condense the rays of light to a focus, a double-concave to scatter them, and a concavo-convex combines both powers.
Fig 5 represents a double-convex lens, Fig. 6 a double-concave, and