| Answer | Crossword Clue |
|---|---|
| biprism | a prism used to split beams |
| biprisms | BIPRISM, a prism used to split beams |
| borescope | an optical device, eg a prism, used to inspect an inaccessible space eg an engine cylinder |
| borescopes | BORESCOPE, an optical device, eg a prism, used to inspect an inaccessible space eg an engine cylinder |
| penpoint | a small thin convex metal device that tapers to a split point, fits into a holder, and is used for writing or drawing |
| SPECTROSCOPICAL | Pertaining to an instrument used to disperse light beams. |
