2. As soon as they take possession of property for the purpose of preserving it, as if they find a ship derelict at sea, or if they recapture it, or if they go on board a ship in distress, and take possession with the assent of the master or other person in possession, they are deemed boua fide possessors, and their possession cannot be lawfully displaced. 1 Dodson~s Rep. 414. They have a lien on the property for their salvage, which the, laws of all maritime countries will respect and enforce. Salvors are responsible not only for good faith, but for reasonable diligence in their custody of the salvage property. Story, Bail. §623.