Measurement.define(:'in.') do |unit|
  unit.alias :in, :inch, :inches, :'"'
  unit.convert_to(:mi) { |value| value / 63_360.0 }
  unit.convert_to(:fur) { |value| value / 7_920.0 }
  unit.convert_to(:ch) { |value| value / 792.0 }