MAPLE  SUGAR  OF  THE  UNITED  STATES. 
73 
given  sugar  for  42  consecutive  years  ;  they  do  not  generally 
last  so  long.  In  certain  cases,  which  must,  however,  be  regarded 
as  exceptional,  as  much  as  104  litres  of  sap  were  obtained  in  24 
hours,  from  which  were  extracted  2  kil.  220  gms.  (nearly  5  lbs.) 
of  crystallized  sugar  ;  but  a  maple  of  ordinary  dimensions  yields 
in  a  favorable  season  113  litres,  producing  2  kil.  500  grs.  (about 
5  J  lbs.).  This  quantity  is  regarded  as  the  annual  yield  of  a 
tree. 
It  may,  consequently,  be  generally  supposed,  that  the  sap 
contains  2-50  of  its  weight  of  drained  sugar.  It  has  been  ascer- 
tained, that,  by  cultivation,  the  Acer  saccharinum  becomes  more 
productive.  Thus  the  forest  maples,  which  have  been  isolated 
by  felling  the  surrounding  trees  which  sheltered  them  from  the 
light  of  the  sun,  or  trees  transplanted  into  orchards,  have  yielded 
a  more  abundant  and  richer  sap,  containing  as  much  as  3  per 
cent,  of  sugar. 
The  extraction  of  the  sugar  from  the  sap  of  the  maple,  presents 
nothing  remarkable;  the  method  followed  is  analogous  to  that 
adopted  for  the  treatment  of  cane  juice.  It  is  necessary  to  boil 
it  as  quickly  as  possible,  because  it  alters  and  ferments  very 
rapidly,  to  such  an  extent  that,  in  some  parts  of  the  United 
States  they  make  with  it  an  alcoholic  liquor,  analogous  to  that 
given  by  cane  juice  which  has  undergone  fermentation  (jlangourin, 
the  chicha  of  South  America).  In  the  preparation  of  maple  sugar, 
a  considerable  quantity  of  molasses  is  obtained,  owing  to  the 
abundance  of  soluble  salts  which  exist  in  the  sap.  It  is  known, 
moreover,  that  by  combustion,  the  maple  leaves  ashes  very  rich 
in  potassa.  The  sap  of  the  maple  contains  acetate,  hydrochlorate 
and  sulphate  of  potassa,  acid  phosphate  of  lime  and  of  mag- 
nesia. 
The  formation  of  sugar  in  the  maples  does  not  take  place  in 
the  roots,  but  in  the  ligneous  body.  The  proportion  of  sugar  of 
the  sap  increases,  until  the  latter  reaches  a  certain  height  in  the 
tree ;  beyond  that  point,  it  undergoes  no  change. 
Maple  sugar  in  the  crude  state,  has  a  brown  color ;  it  contains 
a  little  mannite  ;  this  mannite  is  found  especially  in  the  molasses 
of  this  sugar  with  the  saline  matters.  This  sugar,  which  is  con- 
sumed chiefly  where  it  is  produced,  is  not  refined  ;  it  would  lose 
considerably  in  the  process  of  refining.    It  is  one  of  the  rudest 
