Am.  Jour.  Pharm. 
Dec,  1892. 
Thyroid  Extract. 
635 
beneath  the  chin  nearly  to  the  breast,  so  as  to  expose  the  trachea. 
The  thyroid  consists  of  two  lobes,  situated  in  the  upper  part  of  the 
neck,  one  on  each  side  of  the  trachea,  and  connected  by  a  narrow 
bridge  or  isthmus.  This  isthmus  is  about  one-eighth  of  an  inch 
broad,  and  is  seen  running  across  the  trachea  just  below  the  larynx, 
on  about  the  third  or  fourth  cartilage  ring.  It  is  reddish  in  color, 
but  sometimes  very  pale.  Tracing  it  round  on  either  side  of  the 
trachea,  the  two  lobes  are  easily  found.  Each  lobe  is  from  i-i  ]/2 
inch  long,  about  ^  inch  broad,  shaped  like  an  almond,  and  of  firm 
and  compact  texture.  The  color  is  dark  red.  Remove  the  lobes 
by  means  Of  the  forceps  and  scalpel,  as  free  as  possible  from  the 
surrounding  connective  tissue,  and  transfer  them  at  once  to  the 
bottle. 
To  prepare  the  extract,  cut  up  the  glands  into  transverse  slices 
on  a  clean  glass  or  earthenware  plate  which  has  been  rinsed  in  5 
per  cent,  carbolic  acid  solution.  All  the  utensils  employed  in  the 
subsequent  operations  must  be  rinsed  in  the  same  fluid.  Place  the 
sliced  glands  in  a  mortar  with  some  ordinary  glass  tubing — about 
two  inches  to  each  pair  of  glands  will  be  found  sufficient.  Grind 
the  whole  up  together  until  the  glands  are  thoroughly  disintegrated, 
then  add  a  mixture  of. equal  parts  of  glycerin  and  water  in  the 
proportion  of  one  fluid  drachm  to  each  pair  of  glands.  The  mix- 
ture of  glycerin  and  water  must  be  first  sterilized  by  boiling  for  a 
few  minutes,  and  then  cooled.  After  well  triturating,  transfer  the 
contents  of  the  mortar  to  a  stoppered  bottle  or  jar,  add  a  small  piece 
of  thymol,  and  macerate  for  twenty-four  hours.  At  the  expiration 
of  this  period,  squeeze  out  the  fluid  through  a  piece  of  muslin,  by 
means  of  the  fingers  (previously  dipped  into  5  per  cent,  carbolic 
acid  solution),  and  filter  through  a  double  layer  of  paper  under  pres- 
sure. The  paper  may  be  sterilized  by  immersion  in  boiling  water. 
Under  a  pressure  equal  to  about  1 5  inches  of  mercury  a  nearly  clear 
filtrate  of  a  pale  red  color  is  obtained,  measuring  about  the  same 
volume  as  the  fluid  added  to  the  glands,  since  the  glands  themselves 
exude  fluid  when  pounded  in  the  mortar,  and  by  filtering  under 
pressure  very  little  fluid  is  lost  in  the  residue  remaining  on  the 
filter, 
If  access  cannot  be  had  to  a  pressure  filter,  one  must  be  content 
with  pouring  off  the  supernatant  fluid  after  the  twenty-four  hours 
maceration,  because  filtration  under  ordinary  conditions  proceeds  too 
