It is the rule that where one surety obtains security for his indemnity before he became bound on his obligation, or wherever indemnity obtained by him would inure to his co-sureties, he, the surety, is bound to protect, such security for his co-sureties, and if by his act the security is lost, his co-sureties are relieved from their liability to make contribution to him, to the extent to which they are injured; so where a surety by his own negligence loses the security of a lien on certain property, he thereby releases his cosureties from contribution to the extent of the hen so lost.58