(57) The sliding rule comprises a flat, window-bearing sheath of a stiff material, in
which a sliding tablet of the same material is received, the sheath and the sliding
tablet bearing correlated inscriptions or pictures. According to the invention, the
sliding rule is made from a single blank of said stiff material, comprising a first
and a second board (10, 12), of which at least one has windows, integrally joined
and folded one upon the other and laterally bonded to form said sheath, and a third
board (14) which is end-joined to said second board through an intermediate area (23),
and is folded between said first and second board around a folding line (18) at the
midline of said intermediate area, the intermediate area being removed for using the
sliding rule, said third board acting as sliding tablet.
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