Friction Quotes - page 2
We had a large old-fashioned battery, a wet cell, in the kitchen, hooked up to an electric bell. The bell was too complicated to understand at first, and the battery, to my mind, was more immediately attractive, for it contained an earthenware tube with a massive, gleaming copper cylinder in the middle, immersed in a bluish liquid, all this inside an outer glass casing, also filled with fluid, and containing a slimmer bar of zinc. It looked like a miniature chemical factory of sorts, and I thought I saw little bubbles of gas, at times, coming off the zinc. The Daniell cell (as it was called) had a thoroughly nineteenth-century, Victorian look about it, and this extraordinary object was making electricity all by itself-not by rubbing or friction, but just by the virtue of its own chemical reactions.
Oliver Sacks
The whole science of heat is founded Thermometry and Calorimetry, and when these operations are understood we may proceed to the third step, which is the investigation of those relations between the thermal and the mechanical properties of substances which form the subject of Thermodynamics. The whole of this part of the subject depends on the consideration of the Intrinsic Energy of a system of bodies, as depending on the temperature and physical state, as well as the form, motion, and relative position of these bodies. Of this energy, however, only a part is available for the purpose of producing mechanical work, and though the energy itself is indestructible, the available part is liable to diminution by the action of certain natural processes, such as conduction and radiation of heat, friction, and viscosity. These processes, by which energy is rendered unavailable as a source of work, are classed together under the name of the Dissipation of Energy.
James Clerk Maxwell