ON  THE  MEDICAL  PLANTS  OF  MICHIGAN. 
29 
samea  forms  one  of  the  most  beautiful  of  ornamental  shade  trees, 
from  its  perfect  proportions  and  graceful  form  ;  its  juice,  which 
is  so  much  employed  as  a  stimulant,  expectorant,  and  vulnery, 
is  collected  in  the  northern  peninsula,  by  the  Ojibway  Indians 
to  some  extent,  but  more  profitably  by  the  attachees  of  the  Hud- 
son's Bay  Co.  The  Indian  method  of  collecting  it  is  very  prim- 
itive, and  consists  of  piercing  the  external  hardened  coating  of 
the  blister-like  exudations  of  juice,  and  receiving  the  contents  in 
bottles.  Prepared  in  this  way,  it  is  of  a  beautiful,  clear,  light- 
straw  color,  and  of  a  pleasant,  aromatic  odor. 
The  A.  Canadensis,  besides  a  valuable  timber,  yields  a  bark 
important  to  the  tanner,  the  inner  portion  of  which  is  often  used 
in  medicine  for  its  astringency,  and  also  the  commercial  oils  of 
hemlock  and  spruce,  and  hemlock  gum,  or  Canada  pitch.  The 
habitat  of  this  tree  is  usually  near  streams,  and  in  swampy  spots, 
growing  with  the  tamarac,  from  which  it  is  easily  distinguished  by 
the  fact  of  its  losing  its  leaves  in  the  spring,  while  the  latter 
loses  them  in  the  fall. 
There  are  two  methods  of  collecting  the  resin  of  the  hemlock, 
one  of  which  consists  of  cutting  cup-like  incisions  into  the  body 
of  the  living  tree,  and  removing  the  soft  resin  as  it  exudes  ;  the 
other,  and  most  common  one,  is  to  remove  the  wood  and  bark 
around  the  knobs  or  knots  of  the  felled  trees,  which  are  rich  in 
resin ;  these  being  placed  in  water  in  a  large  kettle,  the  resin  is 
boiled  out,  and  rising  upon  the  top  is  skimmed  off  and  further 
purified  by  remeltingand  straining.  The  product  of  this  method 
is  not  so  good  as  that  by  the  former  one,  the  heat  to  which  it  is 
exposed  necessarily  driving  off  much  of  the  essential  oil.  Not 
content,  however,  with  making  this  gum  by  an  inferior  method, 
the  collectors  often  put  their  gums  into  market  sophisticated 
with  common  resin  to  the  extent  of  seventy  per  cent.  The  com. 
mercial  oils  of  spruce  and  hemlock  are  one  and  the  same  thing ; 
and  are  distilled  from  the  boughs  of  the  Abies  Canadensis.  The 
mode  of  proceeding  is  as  follows,  related  to  me  by  Mr.  David 
Bales,  of  Livingston  County,  who  does  a  large  business  in  distil- 
ling the  oil.  The  trees  are  cut  dowTn  and  the  boughs  collected 
only ;  these  are  cut  up  fine  and  subjected  to  a  distillation  with 
water,  in  a  portable  copper  still  and  worm,  capable  of  holding 
about  one  hundred  gallons,  which  is  so  arranged  that  it  can  be 
transported  in  the  woods,  and  erected  quickly  upon  a  temporary 
