VMS Help PASCAL, Data Types, Real, QUADRUPLE  *Conan The Librarian (sorry for the slow response - running on an old VAX)

  The QUADRUPLE type denotes quadruple-precision real values.   To
  indicate  a  quadruple-precision real number, you must include a
  real number or an integer, the letter Q (or q), and  an  integer
  exponent with its minus sign or optional plus sign.  The largest
  QUADRUPLE  value  is  denoted  by  MAXQUADRUPLE.   The  smallest
  QUADRUPLE   value  is  denoted  by  MINQUADRUPLE.   EPSQUADRUPLE
  denotes the  result  of  subtracting  1.0q0  from  the  smallest
  QUADRUPLE value that is greater than 1.0q0.

  Example:  0.11435Q3
            3362Q2
            0.11825q-4

  On OpenVMS VAX systems, QUADRUPLE uses  the  H_Floating  format.
  On OpenVMS Alpha systems, QUADRUPLE uses the X_Floating format.