Vim and vigour

To do something with vim and vigour means to do it with strength and force. Vim is a word of American coinage from 1850, and supposedly derives from the Latin accusative of vis meaning strength or force, but the OED states that it could be 'a symbolic formation' (whatever that means). Other sources claim it could be simply onomatopoeic because vim sound like something that is revved up and forceful. The alliterative coupling of vim and vigour (or vigor) ocurred a little later after 1850, but before the 20th century.