40  THE  PEPPERMINT  PLANTATIONS  OF  MICHIGAN. 
iron,  about  one  hundred  feet  long,  the  lower  end  of  which  pro- 
jects through  one  side  of  the  cooler,  about  three  inches  from 
the  bottom ;  the  upper  end  of  the  worm  connects  by  a  pipe  of 
similar  material,  with  the  top  of  the  first  described  tub,  which 
tub  is  called  "the  steam  tub,"  or  "still." 
5th.  A  receiver  of  tin,  placed  under  the  opening  of  the  lower 
end  of  the  worm.  The  receiver  is  eighteen  inches  deep,  and  ten 
inches  in  diameter ;  from  the  bottom  of  this  there  issues  a  dis- 
charging pipe  at  an  angle  of  about  25°,  similar  to  the  spout  of 
a  coffee  pot,  and  extends  at  that  angle  to  its  extremity,  which 
stands  at  an  elevation  of  an  inch  or  two  below  the  top  of  the  re- 
ceiver. A  tube  or  pipe  extends  from  the  top  of  the  boiler  to 
the  bottom  of  the  steam  tub,  or  still. 
The  whole  structure  is  generally  covered  with  a  temporary 
shed,  for  protection  against  the  weather — this  covering  being 
open  upon  the  sides.  Underneath  the  covering  is  erected  a 
plank  floor,  twelve  or  fifteen  feet  square,  to  receive  the  Mint. 
This  floor  stands  at  a  level  with  the  top  of  the  steam  tub,  or 
still. 
After  the  boiler  has  been  supplied  with  water,  the  fire  is 
started  in  the  arch,  the  Mint  has  been  drawn  in  from  the  cock, 
and  deposited  on  the  plank  floor,  from  whence  it  is  pitched  with 
a  hay  fork  into  the  still,  and  packed  down  as  it  is  thrown  in, 
by  one  of  the  hands,  who  goes  into  the  tub  for  that  purpose,  and 
packs  it  with  his  feet  until  the  still  can  receive  no  more.  This 
is  called  a  "charge."  The  movable  lid  is  then  adjusted,  and 
the  steam  applied  from  the  boiler.  The  essential  oil  of  the  Mint 
passes  with  the  steam  into  the  worm  ;  is  condensed  with  it,*  and 
passes  into  the  receiver,  where  it  rises  to  the  top  of  the  water. 
As  the  receiver  gets  filled,  the  water  constantly  escapes  by  the 
spout,  while  the  oil  is  dipped  off,  and  placed  in  cans  ready  to 
receive  it.  When  the  charge  is  exhausted,  and  yields  no  more 
oil,  the  steam  is  shut  off ;  the  lid  of  the  steam  tub,  or  still, 
thrown  open,  and  the  reeking  contents  removed  with  hay  forks. 
This  is  called  "  Mint  straw."    Horned  cattle  and  sheep  are 
*  By  exhausting  each  charge  as  rapidly  as  possible,  by  using  steam  under  as 
high  a  pressure  as  the  strength  of  the  boiler  will  warrant,  it  is  found  that  though 
the  yield  of  oil  is  lessened,  it  is  nearly  colorless  and  of  a  firm  odor. 
