among  a  few  places  which  efcaped  my  notice,  I  may
mention  thole  of  Konigtberg  and  Sleltin.  Neverlhe-
lefs,  the  couilbs  of  exchange  of  fuch  places  will  be
found  under  their  refpecStive  heads,  in  the  Defcription
of  rlie  Monies,  Weights,  and  Meafures.
Of  Arhitralions  of  Exchange.
In  regard  to  three  given  places,  there  are  neceflarily
as  many  kinds  of  exchange,  and  there  cannot  be
more.  When  two  of  any  three  exchanges  be  known,
the  objed  of  arbitrjuions,  in  general,  is  that  of  deter-
mining, by  the  combination  of  the  two,  the  third  ex-
change, which  will  be  in  proportion  to  the  former.
Having  before  me  a  quotation  of  all  the  exchanges
current  at  a  certain  place,  and  alfo  a  fimilar  quotation
from  another  place,  I  am  enabled,  by  means  of  a  fuc-
ceffive  combination  of  the  nature  juft  defcribed,  to
difcover  the  proportional  exchange  between  either
of  the  two  places  whence  the  quotations  have  been
received,  and  each  of  thofe  places  which  are  refpec-
tively  enumerated  in  the  quotations  themfelves.
It  is  by  the  determination  of  proportional  exchanges
that  we  are  guided  iu  the  choice  of  an  intermediate
place  affording  the  greateft  advantage,  either  as  the
place  upon  which  we  Qiould  draw,  or  as  that  to  which
we  fliould  remit;  and,  as  we  are  our  own  arbiters  in
fuch  cafes,  the  name  of  arbitration  has  been  given  to
this  kind  of  operations.
