undulating humming

When you're wasting time by reading book reviews written in 1937, and you see "clew", you can instantly find the following (Modern (ha ha thud) English Usage, p. 79):

clew, clue.   The words are the same, but the more recent clue is now established in the usual sense of idea or fact that may lead to a discovery, while clew is retained in the nautical sense, & in the old-fashioned sense skein or ball of wool from which the usual sense of clue has been developed.

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And as usual, the same page has (further) hilarity:

clerk.   The pronunciation -erk, now sometimes heard instead of the long-established -ark, is due to excessive respect for spelling; cf. OFTEN.

climactic is falsely formed from climax, & it may fairly be demanded of the literary critics who alone have occasion for the adjective that they should mend or end it.

'Often' is even better:

often.   Pronounce aw'fn or o'fn. The sounding of the t, which as the OED says is 'not recognized by the dictionaries', is practised by two oddly consorted classes—the academic speakers who affect a more precise enunciation than their neighbours' & insist on de'vil & pi'ktur instead of de'vl & pi'kcher, & the uneasy half-literates who like to prove that they can spell by calling hour & medicine howr & me'disin instead of owr & me'dsn. See PRONUNCIATION.

Pronunciation? I'm not going there.