4. Presumption as to poisonous substances. – Any substance specified as poisonous by rule made under Chapter II or Chapter IV [(Note: Ins. by Act 13 of 1964, sec.3 (w.e.f. 15-9-1964)) or Chapter IVA] shall be deemed to be a poisonous substance for the purpose of Chapter III or Chapter IV [(Note: Ins. by Act 13 of 1964, sec.3 (w.e.f. 15-9-1964)) or Chapter IVA], as the case may be.