http://book.klll.cc/ebooks/subject/14272.opds 2025-11-18T09:23:32Z Books about Optics -- Early works to 1800 Free eBooks since 1971. Project Gutenberg https://book.klll.cc webmaster@gutenberg.org https://book.klll.cc/gutenberg/favicon.ico 25 1 2025-11-18T09:23:32Z https://book.klll.cc/ebooks/33504.opds Opticks : or, A treatise of the reflections, refractions, inflections and colours of light Isaac Newton