Archiving Web content is an important topic for digital libraries. Usually, Web archiving systems freely can collect, preserve and provide. However, Web archiving systems have disadvantages: it is difficult to collect all versions of a resource. We proposed a Web archiving system which is designed to collect resources in accordance with a resource archiving policy determined by the person or organization which provides the resources on the Web. This system was designed without damage to the Web archive by reorganization. The Web archives should cooperate to reduce damage by the reorganization, and the cooperative task is to split archive and convert schema. We call this cooperative task the merge method. This paper describes the model of the Web archiving system which have functions of split and merge archives, and a prototype system implemented based on the model.