By the help of the preceding operations the documents, all the documents, let us suppose, of a given class, or relating to a given subject, have been found. We know where they are; the text of each has been restored, if necessary, and each has been critically examined in respect of authorship. We know where they have come from. It remains to combine and classify the materials thus verified. This is the last of the operations which may be called preparatory to the work of higher (or internal) criticism and construction.