17. The Government may, from time to time, by notification in the official Gazette, declare that any substance which appears to the Government to be specially dangerous to life or property, by reason either of its explosive properties or of any process in the manufacture thereof being liable to explosion, shall be deemed to be an explosive within the meaning of this Act, and the provisions of this Act (subject to such exceptions, limitations, and restrictions as may be specified in the notification) shall accordingly extend to that substance in like manner as if it were included in the definition or the term “explosive” in this Act.