from The American Heritage® Dictionary of the English Language, 5th Edition.
- noun An instrument that combines a solar telescope and a spectroscope and is used to observe a narrow band of solar radiation.
from Wiktionary, Creative Commons Attribution/Share-Alike License.
- noun An
instrumentused for observing solar radiation.
from Wiktionary, Creative Commons Attribution/Share-Alike License
He later built a spectrohelioscope, one of two in Britain, used for solar observation in the elemental light bands of the spectrum, which directed the sun's light through a succession of mirrors into his observatory in the basement of his house.