Petitioners also question the findings and conclusion of the Labor Arbiter and the NLRC that what caused private respondent in jumping overboard was the unmitigated pain he was suffering which was compounded by the inattention of the vessel’s captain to provide him with the necessary treatment inspite of the fact that the ship was moored for about two weeks at the anchorage of Takehara, Japan; and, that private respondent’s act was a desperate move to protect himself and to seek relief for his physical suffering.  Petitioners contend that the findings and conclusions of the Labor Arbiter and the NLRC which were affirmed by the CA are based on conjecture because there is no evidence to prove that, at the time he jumped ship, private respondent was really suffering from an ankle injury.   It is true that no substantial evidence was presented to prove that the cause of private respondent’s confinement in a hospital in Takehara, Japan was his ankle injury.  The Court may not rely on the letter marked as Annex “B” and attached to private respondent’s Position Paper because it was unsigned and it was not established who executed the same.[17]  However, the result of the x-ray examination conducted by the LLN Medical Services, Inc. on August 26, 1996, right after private respondent was repatriated to the Philippines, clearly showed that there is a soft-tissue swelling around his ankle joint.[18]  This evidence is consistent with private respondent’s claim that he was then suffering from an ankle injury which caused him to jump off the ship.   As to petitioners’ contention that private respondent could not have traversed the distance between the ship and the shore if he was indeed suffering from unbearable pain by reason of his ankle injury, suffice it to say that private respondent is an able-bodied seaman and that with the full use of both his arms and the help of a life jacket, was able to reach the shore.   As correctly defined by petitioners, desertion, in maritime law is:   The act by which a seaman deserts and abandons a ship or vessel, in which he had engaged to perform a voyage, before the expiration of his time, and without leave.  By desertion, in maritime law, is meant, not a mere unauthorized absence from the ship, without leave, but an unauthorized absence from the ship with an intention not to return to her service; or as it is often expressed, animo non revertendi, that is, with an intention to desert.[19] (emphasis supplied)