[F] ‘Molecule’ would be the more appropriate name for such a particle.  Unfortunately, chemists employ this term in a special sense, as a name for an aggregation of their smallest particles, for which they retain the designation of ‘atoms.’

     [G] ’At present more organic analyses are made in a single
     day than were accomplished before Liebig’s time in a whole
     year.’—­Hofmann, Faraday Lecture, p. 46.

[H] In the preface to his Mecanique Chimique M. Berthelot declares his object to be ’ramener la chimie tout entirere ... aux memes principes mecaniques qui regissent deja les diverses branches de la physique.’

[I] This is the more curious, as Ampere’s hypothesis that vibrations of molecules, causing and caused by vibrations of the ether, constitute heat, is discussed.  See vol. ii. p. 587, 2nd ed.  In the Philosophy of the Inductive Sciences, 2nd ed., 1847, p. 239, Whewell remarks, a propos of Bacon’s definition of heat, ’that it is an expansive, restrained motion, modified in certain ways, and exerted in the smaller particles of the body;’ that ’although the exact nature of heat is still an obscure and controverted matter, the science of heat now consists of many important truths; and that to none of these truths is there any approximation in Bacon’s essay.’  In point of fact, Bacon’s statement, however much open to criticism, does contain a distinct approximation to the most important of all the truths respecting heat which had been discovered when Whewell wrote.

[J] Perhaps I ought rather to say Button’s axiom.  For that great naturalist and writer embodied the principles of sound geology in a pithy phrase of the Theoris de la Terre:  ’Pour juger de ce qui est arrive, et meme de ce qui arrivera, nous n’avons qu’a examiner ce qui arrive.’

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