WEIGHTS  AND  MEASURES  171
selves  a  system  in  which  the  various  measuies  have  no
common  inter-relation,  and  of  which  the  tables  in  use  in
the  United  Kingdom  and  the  United  States  proceed  on
no  one  notation,  but  skip  lightly  from  dozens  to  scores,
from  sevens  to  fours,  from  a  decimal  to  a  duodecimal  notation. ­
  In  this  last  respect  the  Chinese  are  wiser,  and
with  two  exceptions  base  their  tables  on  a  purely  decimal
notation  ;  but  in  their  disregard  of  any  common  relation
between  the  different  measures,  they  are  on  the  same
footing  as  ourselves.
While  in  theory  their  tables  are  based  generally  on
a  decimal  notation,  the  Chinese  would  not  be  Chinese  if,
in  applying  this  theory  to  practice,  they  did  not  make  some
differences,  perfectly  recognised  and  accepted  as  the  custom
of  the  trade  and  place.  Thus  the  table  gives  100  kin
(catty)  as  making  1  tan  (picul)  ;  but  at  Amoy  the  picul  of
indigo  is  no  catties,  of  white  sugar  95  catties,  and  of  brown
sugar  94  catties  ;  of  rice  the  picul  at  Shanghai  is  100  catties,
at  Amoy  140  catties,  and  at  Foochow  180  catties  ;  for
tribute  rice  the  stipulated  picul  is  120  catties,  but  at  Nanking ­
  it  is  140  catties.  These  are  enough  to  illustrate  this
form  of  irregularity  ;  but  generally  the  purpose  of  this
chapter  is  to  consider  only  the  standards  accepted  at  each
place  by  the  guilds  concerned.
Weight
As  in  England  and  America  16  ounces  make  1  pound,
in  China  16  liang  (tael)  make  1  kin  (catty),  constituting  one
of  the  two  exceptions  to  the  purely  decimal  system  ;  then
100  catties  make  1  picul.  In  practice  quantities  of  ordinary
commodities  are  usually,  and  in  exact  accounts  invariably,
stated  in  the  single  unit  of  catty,  even  when  the  amount  is
millions  ;  and  for  valuable  articles,  such  as  musk,  in  taels,
even  to  the  amount  of  thousands.  The  catty  generally  known
to  foreigners  is  that  imposed  by  treaty  as  the  weight  to
be  used  for  levy  of  Customs  duty,  21&amp;  ounces  avoirdupois,  as
stipulated  by  the  British  treaty,  604-53  grammes  as  stipulated ­
  by  the  French  treaty,  the  two  differing  by  0  4  grammes