hydroscope
noun
hy·dro·scope
: a device for enabling a person to see an object at a considerable distance below the surface of water by means of a series of mirrors enclosed in a steel tube compare water glass
hydroscopic adjective
¦⸗⸗¦skäpik
or less commonly hydroscopical
-pə̇kəl
Word History
Etymology
International Scientific Vocabulary hydr- + -scope; probably originally formed as Italian idroscopio