Secondary evidence permissible where originals are unavailable, destroyed, immovable, public, certified-copyable, admitted, or numerous collections. Section 60 permits secondary evidence of a document's existence, condition, or contents when the original cannot be produced because it is with the adverse party or beyond process, admitted in writing, destroyed or lost without the offeror's fault, not easily movable, is a public document, may be evidenced by a certified copy, or where numerous originals make court examination impracticable; the Explanation specifies which forms of secondary evidence are admissible under each circumstance.