14 сентября, 2015 
Pokraskin For by pressing such Glasses together their parts easily yield inwards, and the Rings thereby become sensibly broader
Isaac Newton, Opticks} p. 201
The quest for molecular adhesion started with Newton’s two fundamental ideas; that polishing glasses smoother would allow more intimate contact, and that the small movements of the surfaces towards each other could be measured by the interference patterns formed by light waves in the narrow gaps between the bodies. Newton had seen the black spot and the colored rings at the contact of two telescope lenses, though he deferred to Robert Hooke in his earlier observations of “ye apparition of a black spot at ye contact of two convex glasses,”2 when he made his famous statement about seeing further “by standing on ye shoulders of Giants.” Of course, Newton did not know about molecules, nor about molecular forces and their influence on elastic deformation. so he could not find the simple connection between the black spot size, the applied force, and the molecular adhesion. Two hundred years were to elapse before these relations could emerge. However, Newton’s idea of seeking out smooth surfaces and of measuring their very small movements in contact through interference methods persisted and ultimately led to the successes described in this chapter. The first experimenters, for example Tomlinson and Bradley, followed Newton by working on glass and this work reached its peak in the measurements of Derjaguin and Sparnaay in the early 1950s. However, glass was too rough and was replaced by smooth mica which had been first studied in 1930 by Obreimoff. Using mica allowed
molecular contact to be studied in depth by Tabor, Winterton and Israelachvili. Polymer surfaces were also smooth enough to give reliable adhesion, as defined initially by Rivlin, leading eventually to the currently accepted theory of molecular adhesion.
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