Not exactly relating to this pub, but the following has been found in the paper below and the name of the pub is the same.

Lancashire Evening Post 02 September 1931

ODD SIGN.

In Blackfriars-road, London, there is to be seen the odd sign of "The Dog's Head in a Pot." How many centuries it has hung there nobody knows. It was a shop sign as long ago as Henry VIII.'s reign, and was adopted by the humorists of the period to typify the slatternly, housewife. A woodcut showing a woman wiping a plate upon the curly tail of a dog, who has his head inside an iron pot and is obviously licking it out, is mentioned among the jests of the time.

The "caption" is in verse:—

All sluts behold, take a view of me,

Your own good housewifery to see.

It is, methinks, a cleanly care

My dishclout in this sort to spare;

Whilst dog, you see, doth lick the pot,

His tail for dishclout I have got.

It is rumoured that the sign is to go to America.