set the Thames on fire

Unknown. Suggested to derive from a misconstrual of temse (“sieve”): thus, to work so vigorously as to heat a sieve by friction. Alternatively, a reference to lightning strikes which sometimes occurred along the Thames, occasionally setting trees on fire or causing death in unusual manner. Otherwise simply by hyperbole, from the improbability of setting a river on fire (although the image might sound like a familiar reference to the Great London fire of 1666).

• "The baronet will never set the Thames on fire, but there seems no harm in him."
• "They intend to send a wire / To the moon — to the moon; / And they'll set the Thames on fire / Very soon — very soon"
• "Do you remember when you jumped into the water after the flowers? I fancy it was then you really set the Thames on fire."
• "My head is spinning round / my heart is in my shoes, yeah / I went and set the Thames on fire, oh / now I must come back down."

• set the world on fire