Source — Robert Moray, “Some Experiments propos’d in relation to Mr. Newton’s Theory of light,” with Newton’s observations, Philosophical Transactions 83, 20 May 1672, pp. 4059–4062. Transcription — Newton Project, University of Oxford. https://www.newtonproject.ox.ac.uk/view/texts/normalized/NATP00011 Checked 14 September 2026.
Procedures
Moray proposes changing prism coverage, movement, and placement. Newton reports that covering prism ends changes image breadth without changing its length; rotating a prism moves the image, with qualifications about wall and prism orientation. He also discusses lenses, aperture, and placement of a second prism.
Use in Game Extensions
Add one controlled change, such as narrowing an aperture, while preserving an existing comparison. State what stays fixed and which observation changes. Cite the particular procedure used. Do not turn every historical observation into a universal optical rule.
Questions
Which variable changed? Which conditions stayed fixed? Does a changed image support the proposed explanation, or merely rule out one alternative?