[interroboink]

From "Plenty of Room at the Bottom"[1]:

  What would happen if I print all this down at the scale we have been
  discussing? How much space would it take?  It would take, of course, the
  area of about a million pinheads ...  All of the information which all of
  mankind has every recorded in books can be carried around in a pamphlet
  in your hand — and not written in code, but a simple reproduction of
  the original pictures, engravings, and everything else on a small scale
  without loss of resolution.

Need a good magnifying glass, though (:

[1] https://web.pa.msu.edu/people/yang/RFeynman_plentySpace.pdf

[yencabulator]

Yeah electron microscopes are very much not "practically indestructible" on the scale of civilization-wide disturbances.

Going from "25,000x -> encyclopedia on pinhead" to "100x (microfilm scale) -> encyclopedia on a 5x10cm metal sheet" is probably a better bet.