September 2010 Issue 102

	

 by John Merchant

In the five and a half thousand years since the Ancient Egyptians invented papyrus, mankind has been searching for a more practical and durable way to record the thoughts, images and transactions that humans find so necessary.

The Essenes, or Sadducees, depending on which scholars you believe, advanced the technology with parchment, but the propagation of sheep or goats could never have kept up with today’s demand.

We humans just love to write stuff down.  As the old joke says, the Law started out with a couple of stone tablets, and now fills thousands of libraries.  For years it was believed that paper and ink would last forever, given proper care.  Now there is increasing concern that posterity is a lot less distant than we originally thought, so the scramble to preserve the written and printed word is of prime interest.

The first “salvation” was thought to be the wax cylinder, the heart of the putative dictating machine, which evolved into plastic discs, then belts, until it was replaced by magnetic tape.  Tape seemed like a winner, and lasted from the 1950’s until the 90’s, but the thin, delicate coating of ferrous oxide that “memorized” the data, wore away after several playings, and also was vulnerable to corruption from the proximity of other magnetic devices such as loudspeakers.

With the advent of digital technology, the possibilities for durable record keeping expanded beyond all expectations.  Progress was only constrained by the time it took to invent devices that could make use of it.  Initially, the recording medium still was magnetic tape, but tape wear and damage was less critical with information that had been converted to the binary 0 and 1 codes of digitized data.

No longer was reading, interpretation or reproduction dependent on the clarity of handwriting or typescript.  Computers had the capability to make some “assumptions” about what a corrupted word, image or sound really meant, and clean up the record accordingly.  Ironically, after the computer, the next digital devices to come along were printers, so we were back to ink and paper!

Many printer users made the erroneous assumption that advances in technology had somehow increased the durability of the inks and toners used in these devices.  In fact, even today, the predicted lifetime of printer ink images is not much beyond 100 years.  Even more ironic is the fact that few of us feel really secure unless we print out what we store in our computers.  The promised paperless office never happened.

Probably the next, most important invention was the scanner.  Scanners can convert text on paper, and more importantly, images, to digital format.  So now we have the capability to copy books and maps, engineering drawings and photographs into the computer. Scanners became so good that complex changes in currency bills were necessary to prevent forgeries.  Whole libraries are being, or will be, scanned for computer storage.

So the acquisition and recording of data has come a long way, but the durability of data storage still has many question marks.  Hard drives are mechanical devices that wear out and fail.  Flash drives offer more durability and have no moving parts. They come in a variety of formats such as the USB Flash Drive that plugs into your computer, or the card that slots into your digital camera and photo printer. Storage capacities can range from a few megabytes to 256 billion bytes with steady improvements in capacity.

Some allow one million write or erase cycles, but withal, have only a 10-year guaranteed data retention capability.

Clearly this is far from adequate for archival purposes, and doesn’t even begin to approach  the longevity of the parchment and ink of the Dead Sea Scrolls.  So it seems we’ve made incredible progress in the acquisition and recording of massive amounts of data, but none at all in the preservation of what we acquire.

Extraordinary measures such as storing magnetic tape and other media deep within mountains and worked-out salt mines to protect them from decay or corruption, goes some way towards delaying disintegration, but it doesn’t eliminate it.  New forms of data storage using biological media are in the pipeline, but it remains to be seen how durable they will be. Perhaps we must resign ourselves to constantly re-recording our data, onerous though that may be.

© John Merchant 2010

This entry was posted by John Merchant on Monday, February 1st, 2010 at 12:00 am and is filed under Science Stuff. You can be notified of any comments on this entry through the RSS 2.0 feed. You can leave a comment in the box at the bottom of the post.

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