Nassau Senior (1790-1864)
From Literary Anecdotes (1800-1829)

WE spoke of Senior. He has, said Hayward, infinite aplomb. On one occasion when Moore was singing at Bowood, the poet was annoyed by the scratching of the pen with which Senior was writing, and stopped.

'Pray go on,' said Senior, 'you don't interrupt me.'

From Grant Duff, Notes, i. 187.