Bausch & Lomb Spectroscope

Spectroscope is in the style of the original Bunsen-Kirchhoff design. A spectroscope filters light through a narrow slit, dispersing the light into a visible spectrum. The earliest spectroscope was invented by Robert Bunsen and Gustav Kirchhoff in Germany in 1859, and their basic design was not substantially altered until the introduction of the mass spectrometer in 1919.