Assertion: newton's telescope | /r/HasProperty | first practical reflecting
Facets:
Source sentences:
text: Newton built the first practical reflecting telescope and developed a sophisticated theory of colour based on the observation that a prism separates white light into the colours of the visible spectrum.
text: Newton built the first practical reflecting telescope in 1668; he also developed a theory of light based on the observation that a prism decomposes white light into the colours of the rainbow.
text: Newton built the first practical reflecting telescope in 1668.