Measurement  of  Wall  Surfaces. —
A  common  application  of  square
measure  in  the  household  is  in  esti-
mating material  and  labor  for  the
treatment  of  wall  surfaces  by  paper
hanging,  plastering,  painting,  or  cal-
cimining.  All  of  these  are  usually
'computed  by  the  square  yard.
Wall  paper  is  sold  by  the  roll,
which  is  usually  18  inches  wide  and  8
yards  in  length.  Or  in  double  rolls
of  the  same  width,  16  yards  long.
These  are  counted  as  2  rolls  each.
They  economize  waste  in  cutting.
These  are  the  dimensions  of  most
wall  papers  made  in  America,  and
may  be  taken  for  granted  unless
otherwise  specified.  Imported  papers
differ  as  to  the  length  and  width  of
the  roll.
Borders  or  friezes  are  sold  by  the
yard.  They  vary  in  width  from  3
inches  upward.
Cost  of  Hanging  Wall  -Paper. — It
is  not  possible,  as  a  rule,  to  find  in
advance  the  exact  cost  of  papering  a
room.  The  measurement  of  the  room
will,  however,  assist  in  making  an  es-
timate of  the  number  of  rolls  re-
quired. The  actual  number  to  be  paid
for  can  be  determined  only  after  the
papering  has  been  done.  Then  all
rolls  that  have  been  cut  jjiust  be  paid
for,  the  uncut  rolls  being,  as  a  rule,
allowed  to  be  returned.
When  estimating  the  number  of
rolls  of  paper  required  for  papering
a  room  of  ordinary  height  (i.  e.,  if
the   distance    from   the  baseboard   to


WEIGHTS   AND    MEASURES


751


the  border  is  not  mare  than  8  feet),
first  measure  around  the  room,  leaving
out  the  widths  of  the  doors  and  win-
dows; then  allow  one  double  roll  or
two  single  rolls  for  every  7  feet.
