If a suit in equity be set for hearing as to any defendant, it shall be heard as to him unless his interests be so connected with those of other defendants in the suit that it would be improper to decide upon their interests separately. And though there be such connection, a defendant as to whom the case has been set for hearing may have an order upon the plaintiff to use due diligence to mature the cause for hearing as to the other defendants, and, unless it be so matured within such time as the court may deem reasonable, shall be entitled to a hearing or dismission of it as to him