 Biographer Weissweiler does not dismiss the possibility that Busch 's increasing alcohol dependence hindered self @-@ criticism . He refused invitations to parties , and publisher Otto <unk> sent him to Wiedensahl to keep his alcohol problem undetected from those around him . Busch was also a heavy smoker , resulting in symptoms of severe <unk> poisoning in 1874 . He began to illustrate drunkards more often . 
