anchor.diff:           (multiple-value-bind (deg boundp)
                (slot-value* object 'degree)
              (cond
  +             ((and boundp (subtypep (class-of object) 'kilogram))
  +              (error "FIXME: Printed representation for Kilgraom measurements")
  +              ;; FIXME: The fact that the base quanity, kilogram, is
  +              ;; actually a unit defined with a prefix over the base
  +              ;; unit for mass, gram -- though it may seem like
  +              ;; a cliched anachronism, but it is a standardized
  +              ;; anachronism -- in effect, it may serve to require
  +              ;; that all of the prefix/degree/scaling procedures
  +              ;; would be, henceforward, "Buried" within methods
  +              ;; specialized onto generic functions.
  +              ;;
  +              ;; For instance, the function SCALE-FOR-SI-DEGREE should
  +              ;; be defined as to dispatch onto the measurement unit
  +              ;; type for the scale. When the measurement is a
  +              ;; KILOGRAM, then it must be scaled with +3 implicit
  +              ;; degree, in addition to the measurement degree
  +              ;; e.g. new name and lamba list:
  +              ;;  SCALE-SI (MEASUREMENT &OPTIONAL EE-P)
  +
  +              ;; similar for SHIFT-MAGNITUDE  (cf. RESCALE)
  +              ;; e.g new lambda list:
  +              ;;  SHIFT-MAGNITUDE MEASUREMENT NEW-DEGREE
  +
  +              ;; Both changes will require redefinitions of the
  +              ;; respective functions, and changes to all calling
  +              ;; functions. 
  +              )
  +             
                (boundp
                 (multiple-value-bind (adj-mag deg)
                     (scale-for-si-degree mag deg)
  
positive.code: 
  
  (defun prefix-of (m)
    "Select and return a PREFIX object representative of the scalar
  magnitude and degree of measurement M. The second return value will
  represent the magnitude of M scaled for decimal degrees of the prefix
  
negative.code:             (deci  -1 "d" :|d|)
              (centi  -2 "c" :|c|)
              (milli  -3 "m" :|m|)
              (micro  -6 #.(string (code-char #x3BC)) :|u|)
              (nano  -9 "n" :|n|)
              (pico  -12 "p" :|p|)
              (femto  -15 "f" :|f|)
  