Dr. Doran, "Their Majesties' Servants." Annals of the English Stage…
“ Booth could, after all, perhaps, occasionally be languid without the excuse of illness. He would play his best to a single man in the pit whom he recognised as a playgoer, and a judge of acting; but to an unappreciating audience he could exhibit an almost contemptuous disinclination to exert himself. On one occasion of this sort he was made painfully sensible of his mistake, and a note was addressed to him from the stage-box, the purport of which was to know whether he was acting for his own diversion or in the service and for the entertainment of the public? ”
