Put your lips together and blow

From Chapter 7, ' Putting Sounds on the Road', of A Mouthful of Air by Anthony Burgess:

Another trick of utterance is not in the service of entertainment but concerned with serious communication. I refer to the whistled languages in use among the Mazateco Indians of Oaxaca in Mexico, the peasants of La Gomera (one of the Canary Islands) and certain Turks. [...]
[Whistling] is conceivably a medium of communication older than speech, and it relates man to birds, otters and guinea pigs. Taboos are attached to it. 'A whistling woman, a crowing hen/ Whistled the devil out of his den.' Witches whistle (thrice), also whores. [...]
In 1891 R. Verneau published a book called Cinq Ans aux Iles Canaries. He described how the peasants of La Gomera whistled at each other across the deep valleys or barrancos that cross the island radially.

The Wikipedia article on whistled language notes, as does Burgess, that this is far easier when the reference language (should that be referent?) is tonal.

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Burgess's suggestion that whistling is an older form of communication than speech made me think of a story in which a man is perpetually plagued by a whistling which only he can hear, and which turns out to be form of communication. Questions: what message is the whistling imparting, and what sin has he committed to be so haunted? One can imagine a half-comic moment in which a child's guinea-pig whistles from its cage and he starts back in horror.

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'I know all that, my angry little weasel,' the barbarian replied, tugging the Mouser back. 'And the idea of Fissif escaping displeases me. but putting my bare neck in a trap displeases me more. Remember, they whistled.'
'Tcha! They always whistle. They like to be mysterious. I know these thieves, Fafhrd. I know them well. And you yourself have twice entered Thieves' House and escaped. Come on!'

From the story 'Thieves' House' by Fritz Leiber.

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Not quite at Disraeli's level ('Many thanks for your book: I shall lose no time in reading it'), but impressive nonetheless, an Evening Standard blurb on the cover of Lipstick Jungle:

Candace Bushnell is some sort of genius.

Supply your own adjective.