In 1967, Vannevar Bush published a retrospective article entitled "Memex Revisited" in his book "Science Is Not Enough". Published 22 years after his initial conception of the Memex, Bush details the various technological advancements that have made his vision a possibility. Specifically, Bush cites photocells, transistors, cathode ray tubes, magnetic and video tape, "high-speed electric circuits", and "miniaturization of solid-state devices" such as the TV and radio. The article claims that magnetic tape would be central to the creation of a modern Memex device. The erasable quality of the tape is of special significance, as this would allow for modification of information stored in the proposed Memex.