Am.  Jour.  Pharni. ) 
Feb.,  1881.  j 
Absorbent  Cotton. 
53 
Nor  does  the  Beth-a-barra  principle  correspond  exactly  with  chrysa- 
Tobin,  which  Liebermann  and  Seidler  found^  to  be  the  chief  constitu- 
ent of  goa  powder.  TJiat  compound  dissolves  in  strong  potassium 
Jhydrate  solution  with  yellow  color  and  green  fluorescence.  Its  per- 
'Centage  composition  moreover  demands  72*29  per  cent,  of  carbon  and 
•5'22  per  cent,  of  hydrogen.  By  heating  with  caustic  potash  solution 
in  contact  with  air  it  is  changed  into  chrysophanic  acid. 
The  similarity  of  the  Beth-a-barra  principle  in  many  of  its  reactions 
to  these  two  compounds  leads  one  to  suspect  a  relationship.  We  hope 
to  be  able  to  settle  what  this  relationship  is  shortly  by  a  fuller  study 
of  its  reactions  and  derivatives. 
Philadelphia,  Dec.  21,  1880. 
ABSOKBENT  COTTON. 
By  Frank  It.  Slocum. 
Absorbent  cotton  has  in  the  last  few  years  taken  such  an  important 
place  among  the  necessities  and  conveniences  of 'the  pharmacist  and 
physician  that  it  is  very  desirable  for  the  pharmacist  to  be  able  to  pro- 
'Cure  or  himself  manufacture  it.  The  manner  in  which  it  is  prepared 
is  kept  secret,  and  there  is  no  literature  on  the  subject  up  to  the  present 
time,  it  is  believed. 
At  the  request  of  Prof.  Maisch  some  experiments  have  been  made, 
the  following  process  yielding  the  most  satisfactory  results. 
Take  of  the  best  quality  of  carded  cotton  batting  any  desired  quan- 
tity and  boil  it  with  a  5  per  cent,  solution  of  caustic  potassa  or  soda  for 
one-half  hour,  or  until  the  cotton  is  entirely  saturated  with  the  solution, 
and  the  alkali  has  saponified  all  oily  matter.  Then  wash  thoroughly, 
±0  remove  all  soap  and  nearly  all  alkali ;  press  out  the  excess  of  water, 
:and  immerse  in  a  5  per  cent,  solution  of  chlorinated  lime  for  15  or  20 
minutes ;  again  wash,  first  with  a  little  water,  then  dip  in  water  acidu- 
lated with  hydrochloric  acid,  and  thoroughly  wash  with  water ;  press 
■out  the  excess  of  water,  and  again  boil  for  1 5  or  20  minutes  in  a  5  per 
cent,  solution  of  caustic  potassa  or  soda ;  now  wash  well,  dipping  in 
the  acidulated  water  and  washing  thoroughly  with  pure  water.  After- 
wards press  out  and  dry  quickly.  . 
Boiling  with  caustic  alkalies  saponifies  all  oil  and  greasy  matter,  and 
the  soap  formed  is  removed  by  washing ;  if  it  were  not  washed  out 
1 "  Ber.  der  Chem.  Ges.,"  1878,  p.  1003. 
