It’s not possible to go back in time and rewrite the HTTP protocol, but Van de Sompel’s work involves adding to it. He and Michael Nelson are part of the team behind Memento, a protocol that you can use on Google Chrome as a Web extension, so that you can navigate from site to site, and from time to time. He told me, “Memento allows you to say, ‘I don’t want to see this link where it points me to today; I want to see it around the time that this page was written, for example.’ ”