125. 1[ Information as to commission of offences.- No Magistrate or police- officer shall be compelled to say whence he got any information as to the commission of any offence, and no revenue- officer shall be compelled to say whence he got any information as to the commission of any offence against the public revenue. Explanation.--" Revenue- officer" in this section means any officer employed in or about the business of any branch of the public revenue.]