252  North  American  Conifer  cz.  {Am,May%earm' 
worked  two  years  to  195  barrels,  at  $3.50  per  barrel;  after  deducting  the  extra 
expense  involved  by  his  method,  this  would  leave  a  net  balance  of  $410  per  crop 
in  favor  of  the  cup  system.  He  further  claims  that  this  amount  is  still  further 
augmented  if  the  larger  quantity  of  spirit  of  turpentine  and  the  higher  quality 
of  rosin  obtained  from  the  dippings  under  his  system  are  taken  into  account. 
On  the  first  point  he  says  that  fully  one-eighth  of  the  crude  turpentine  brought 
to  the  still  from  the  boxes  consists  of  chips,  sand  and  other  foreign  matter, 
contaminations  from  which  the  product  of  the  cups  is  entirely  free.  On  the 
second  point  he  refers  to  the  high  grades  of  rosin  resulting  from  the  distillation 
of  the  crude  turpentine  from  the  cups,  which  almost  entirely  classes  with  the 
highest  and  higher  grades." 
Apparently  the  question  of  systems  resolves  itself  into  one  of 
boxes  or  cups.  It  is  a  matter  against  trouble  and  expense,  and  it  is 
doubtful  whether  any  other  than  the  present  system  will  be  adopted 
until  scarcity  of  material  drives  the  producers  into  more  economical 
methods. 
The  process  of  dipping  the  turpentine  from  the  boxes  has  been 
described ;  these  dippings  are  first  collected  in  buckets,  which  are 
emptied  into  barrels  in  wagons  and  conveyed  to  the  stills. 
The  distillation  of  turpentine  is  effected  in  copper  stills  set  into 
brick  furnaces.  The  still  usually  holds  from  fifteen  to  twenty  barrels 
of  the  crude  resin.  With  this  "  crude  "  a  little  water  is  added,  and 
the  whole  is  then  warmed  so  as  to  allow  the  chips,  straw  and  other 
light  impurities  to  rise  to  the  surface  and  be  removed  as  far  as 
possible.  The  top  is  then  luted  on  and  connected  with  a  large  con- 
densing worm  in  a  tank  of  cold  water.  When  all  the  joints  have 
been  made  tight,  heat  is  applied  strongly  and  the  distillation  com- 
mences. Water  predominates  in  the  first  portions  of  the  distillate, 
but  soon  a  nearly  pure  oil  is  collected.  In  most  cases  water  is  run 
in  during  the  process,  in  order  to  prevent  the  resin  from  becom- 
ing too|thick  and  charring.  The  spirit  of  turpentine  is  dipped  off 
from  the  surface  of  the  water  and  run  into  barrels,  or  in  some  cases 
into  oirtank  cars.  The  residue  in  the  still,  while  yet  in  a  molten 
state,  is  run  off  by  a  faucet  through  three  strainers  of  wire  cloth, 
and  then  into  barrels ;  this  constitutes  the  commercial  rosin.  The 
rosin  from  the  first  year  resin  is  rated  in  commerce  as  W.  W. 
(water  white)  and  W.  G.  (window  glass).  That  from  the  second 
year's  yield  is  classed  N.  M.  K.,  etc. 
The  following  facts  concerning  yield,  taken  from  the  U.  S. 
Government  Report,  previously  referred  to,  indicate  just  how  the 
