Separation of two plane surfaces

Boyle (plane separation experiment)
The following is a c.1662 "separation of two plane surfaces" experiment performed, in a vacuum, by Robert Boyle, wherein he took to polished plane (flat) marble surfaces, stuck them together, and put them in a vacuum receiver, then, having a weight attached to the bottom plane, with a string attached to the weight, evacuated the vessel, to test the theory, going back to Lucretius, that the formation of a vacuum is what keeps the planes from separating. [3]
In science, separation of two plane surfaces refers to the observed "problem" of the difficulty of "separating" two planes laid one on top of each other at their joint "surface", which, historically, has been used in the two-century long debated about whether or not "nature abhors a vacuum".

The following are related quotes:

“I feel that for a complete explanation, of the question of what is binding material which holds together the parts of solids so that they can scarcely be separated, other considerations might well enter; yet I must not now digress upon this ‘particular topic’ since you are waiting to hear what I think about the breaking strength of other materials which, unlike ropes and most woods, do not show a filamentous structure. The coherence of these bodies is, in my estimation, produced by other causes which may be grouped under two heads. One is that much-talked-of repugnance which nature exhibits towards a vacuum; but this ‘horror of a vacuum’ NOT being sufficient, it is necessary to introduce another cause in the form of a gluey or viscous substance which binds firmly together the component parts of the body. First, I shall speak of the vacuum, demonstrating by definite experiment the quality and quantity of its force [virtù]. If you take two highly polished and smooth plates of marble, metal, or glass and place them face to face, one will slide over the other with the greatest ease, showing conclusively that there is nothing of a viscous nature between them. But when you attempt to separate them and keep them at a constant distance apart, you find the plates exhibit such a repugnance to separation that the upper one will carry the lower one with it and keep it lifted indefinitely, even when the latter is big and heavy.”
Galileo (1638), Dialogues Concerning the Two New Sciences (pgs. 8 + 11) [1]

“In the medieval literature on nature’s ‘abhorrence of a vacuum’, the two most popular demonstrations were the clepsydra and the separation of two plane surface.”
Edward Grant (1981), Much Ado About Nothing [2]

Lucretius had argued that, since the velocity of the air rushing in from the sides to fill the space created by their separation must be finite, therefore a ‘vacuum’ existed at the moment of separation.”
Steven Shapin (1985), Leviathan and the Air Pump (pg. 47) [4]

1. Galileo. (1632). Dialogues Concerning the Two New Sciences (translators: Henry Crew; Alfonso Salvio) (pg. 11). Macmillan, 1914.
2. Grant, Edward. (1981). Much Ado About Nothing: Theories of Space and Vacuum from the Middle Ages to the Scientific Revolution (clepsydra, 7+ pgs, quote, pg. 83). Cambridge.
3. (a) Boyle, Robert. (1669). A Continuation of New Experiments, Physico-Mechanical, Touching the Spring and Weight of the Air and their Effects (diagram, pg. 154) (ΡΊ). Hall.
(b) Shapin, Steven; Schaffer, Simon. (1985). Leviathan and the Air Pump: Hobbes, Boyle, and the Experimental Life (discussion, pg. 47; diagram, pg. 196). Princeton, 2011.
4. Shapin, Steven; Schaffer, Simon. (1985). Leviathan and the Air Pump: Hobbes, Boyle, and the Experimental Life (discussion, pg. 47; diagram, pg. 196). Princeton, 2011.

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