E. Cobham Brewer 18101897. Dictionary of Phrase and Fable. 1898.
Hot as a coal. The expression has an obvious allusion.
To post the coal or cole. To pay or put down the cash. Coal=money has been in use in the sporting world for very many years. Buxton, in 1863, used the phrase post the coal, and since then it has been in frequent use. Probably rhyming slang. Coal, an imperfect rhyme of gool=gold. (See page 248, CHIVY, and page 266, COALING.)
It would not suit me to write even if they offered, to post the cole.Hood.