Hard friction contracts, and soft relaxes; so that those persons that
are relaxed should be rubbed hard, and those that are immoderately
constricted, softly; and when, neither in the one state nor the other,
it is clear that neither the one mode of friction nor the other should
be had recourse to, but as much as possible either extreme ought to
be avoided. For much and hard friction diminishes the bulk of the
body, whilst, on the other hand, little and soft distends it. If the
three different kinds of frictions as to quantity be joined to the
same number as to quality, they will produce nine combinations, as is
stated below. For one of the kinds, as to quantity, for example _much_,
being complicated with the three differences as to quality, I mean the
_hard_, the _soft_, and the _moderate_ as to hardness, will produce
three combinations; and, again, the _little_ being joined to the other
three will produce three more; and the _moderate_ as to quality being
complicated with the same three, will produce three more, as is shown
below: