HELPER’S LECTURE TO COME OFF. – It appears that the author of the “Impending Crisis” has recovered from his recent disappointment, and has resolved to deliver his lecture upon the “Two Systems of Labor” on to-morrow evening. Helper has made on great point. He has satisfied the community that he really exists, that he is not impalpable myth, gotten up by the philosophers of Spruce street, and now he will probably have a large audience. Two shillings to see the identical Helper may be, without disrespect, termed absolutely dog cheap.