Biographer Weissweiler do not dismiss the possibility that Busch 's increasing alcohol dependence hindered self @-@ criticism . He refused invitations to parties , and publisher Otto Basserman 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 nicotine poisoning in 1874 . He began to illustrate drunkards more often .