Preserving the Past - NYTimes.com Re "In a Flood Tide of Digital Data, an Ark Full of Books and Film" (front page, March 4): Brewster Kahle and his colleagues at the Internet Archive, in their efforts not only to digitize books and films but also to collect and preserve the originals, are demonstrating a true understanding about the nature of primary materials. Primary materials are physical objects whose attributes can never be wholly expressed or preserved in copies. The loss or willful destruction of primary materials reduces the cultural heritage and the evidence readers of one era can consult in trying to recreate the history of another. Unfortunately, as representative comments in the article show, many library administrators have little understanding of the nature and importance of primary materials. Instead of acting as the custodians of humanity's cultural heritage, some seek to rob posterity, by "repurposing" their "space" and relegating little-used volumes to landfills. The printed and filmed legacy of the past would be far more secure if its management were separated from those would mindlessly destroy it, and put in the hands of those, like Mr. Kahle, who at least know it when they see it. The writer, a bibliographer, is an editor of Mark Twain's letters.