At  that  date,  1673,  all  of  that  portion  of  the  west  part  of  old  Dun-
stable which  is  now  included  in  Brookline  was  bounded  on  the  south  by
Groton  Plantation,  now  Pepperell,  Mass.,  and  the  present  town  of  Towns-
end,  Mass.;  which  was  then  an  unbroken  wilderness.  Townsend  was
chartered  in  1732;  and  for  many  years  subsequently,  or  until  the  estab-
lishment of  the  Province  Line  in  1741,  its  northeast  corner  was  located
at  the  junction  of  its  east  boundary  line  with  the  north  boundary  line
of  Groton  Plantation.  This  location  probably  never  was,  and  certainly
is  not 'now,  definitely  known.  But  it  is  supposed  to  have  been  about  one
mile  south  of  Townsend's  present  northeast  corner.  The  old  north
boundary  line  of  Townsend  commenced  at  its  said  northeast  corner  and
ran  west,  thirty-one  and  one-half  degrees  north,  until  it  reached  its  ter-
minus somewhere  in  the  present  town  of  Greenville ;  crossing  in  its  course
the  southwest  part  of  Brookline's  present  territory,  and  the  central  part
of  township  No.  1,  now  Mason.
By  the  establishment  of  the  Province  line  in  1741,  that  part  of  Towns-
end  lying  north  of  that  line,  and  east  of  the  east  boundary  line  of  Mason,
became  a  part  of  New  Hampshire;  and  subsequently,  at  Brookline's  in-
corporation, was  included  in  its  charter.  This  was  the  Triangular  Tract
in  question.  It  was  in  the  shape  of  a  scalene  triangle.  As  to  its  bound-
ary lines,  they  have  been  hitherto  somewhat  difficult  to  locate,  because
of  the  lack  of  sufficiently  accurate  data  from  which  to  establish  the  point
at  which  the  old  north  boundary  line  of  Townsend  crossed  the  south
boundary  line  of  Brookline.
