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My best friend Aaron goes through a lot of index cards. Easily a 100 a week I'd bet, filling each one with the polysyllabic facts one must conquer in medical school. He keeps them in boxes specifically designed to hold such cards, and has become quite picky about the brands that he'll acquire.
He knows which ones absorb liquid ink, which ones don't; he knows which are long fibred, which short; always looking in cheap drugstores and expensive stationers for something new, something that will hold his pen's interest for the next week or two. As each pack is opened and consumed, the last is dropped in the box, the newest layer in the striated stack. Together, the layers (of mostly pastels and recycled brown) look like sedimentary rock (the kind we remember visible along highways cut into Appalachian hills).
He announced his most recent find (white cards with thick pink stripes) with the charming thought depicted above, handwritten in his signature blue and mailed to Heather several days ago.