A convict who shall evade the service of his sentence, by leaving the penal institution where he shall have been confined, on the occasion of disorder resulting from a conflagration, earthquake, explosion, or similar catastrophe, or during a mutiny in which he has not participated, shall suffer an increase of one-fifth of the time still remaining to be served under the original sentence, which in no case shall exceed six months, if he shall fail to give himself up to the authorities within forty-eight hours following the issuance of a proclamation by the Chief Executive announcing the passing away of such calamity.
Convicts who, under the circumstances mentioned in the preceding paragraph, shall give themselves up to the authorities within the above mentioned period of 48 hours, shall be entitled to the deduction provided in article 98.