In  man  the  rate  of  secretion  is  proportional  to  the  palatability  of  the
food,  the  smallest  amount,  during  twenty  minutes'  mastication  of  pal-
atable food,  being  30  c.c.  and  the  largest  150  c.c.,  in  a  series  of  156  obser-
vations. A  typical  curve  showing  the  amount  of  the  secretion  is  given
in  Fig.  149.  To  construct  this  curve  the  gastric  juice  was  collected  dur-
ing five-minute  intervals  while  the  man  was  chewing  a  meal  of  average
composition  and  of  his  own  choice.  An  interesting  feature  depicted  on
this  curve  is  that  the  secretion  rate  was  highest  in  the  last  five-minute
period,  this  being  the  time  during  which  the  dessert  was  being  taken,
for  which  this  man  had  a  great  relish.  Quite  clearly  there  was  a  direct
relation  between  the  rate  of  the  secretion  of  the  appetite  juice  and  the
palatability  of  the  food.  It  will  further  be  observed  that  it  took  only
from  fifteen  to  twenty  minutes  after  discontinuing  the  chewing  before
the  juice  returned  to  its  original  level.
