Colours fading to blue with distance; a rebound test
How the green of fields turns bluer far off, plus a test of motion rebounding from a convex surface
A note on aerial perspective observes that, among colours that are not blue, those seen at long distance take on more blue the nearer they already are to black, so the green of fields shifts toward blue more than yellow or white does, and red least of all. A second note sets out an experiment for observing reflected motion: strike a b against a convex surface and set the ground n m opposite it to record the rebound. An arc and a small body are drawn at the top of the sheet.
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Distant colours shift toward blue
Among the colours that are not blue, the one seen at long distance partakes more of blue the nearer it already is to black; conversely a colour keeps its own hue over distance when it is more unlike black. Thus the green of the fields turns to blue more than yellow or white does, while yellow and white change less than green, and red changes least of all.
Experiment on motion reflected off a convex surface
To make an experiment of the reflected motion of a b struck upon the convex, one is instructed to set the ground n m opposite it and there to observe the rebound. The letters b, a, n, m mark the arrangement.