314       NOTES  ON  THE  FLUID  EXTRACTS  OF  BUCHU,  ETC. 
tincture  evaporated  to  6  fl.  oz.  intimately  mixed  with  the  sugar 
and  evaporated  in  a  waterbath  to  one  pint. 
Extr  actum  Serpentarice  fluidum  16  oz.  of  the  root  are  ex- 
tracted with  one  pint  of  95  per  cent,  alcohol,  the  tincture  allowed 
to  evaporate  to  the  consistence  of  a  thin  extract,  which  is  taken 
up  by  4  oz.  95  per  cent,  alcohol  and  intimately  mixed  with 
12  oz.  sugar.  The  residuary  root  is  exhausted  by  diluted  alco- 
hol, evaporated  to  8  fl.  oz.  added  to  the  sugar,  which  is  dissolved 
by  a  moderate  heat,  and  the  extract  is  then  evaporated  to  one 
pint. 
Extraction  Valeriana?  fluidum. — 16  oz.  of  the  root  are  dis- 
placed with  half  a  pint  of  ether  and  1  pint  of  95  per  cent,  alcohol, 
the  tincture  allowed  to  evaporate  to  8  fl.  oz.,  the  clear  liquid  is 
incorporated  with  10  oz.  of  sugar,  the  precipitated  resin  is  dis- 
solved in  3  fl.  oz.  of  95  per  cent,  alcohol  and  added  to  the  sugar. 
The  root  is  then  exhausted  with  diluted  alcohol,  the  tincture 
evaporated  to  a  syrupy  consistence  and  added  to  the  sugar,  which 
is  to  be  dissolved  by  the  aid  of  a  waterbath  ;  the  resulting  fluid 
extract  is  evaporated  to  one  pint. 
To  these  directions  allow  me  to  add  a  few  comments : 
Though  three  of  the  above  articles  contain  a  certain  amount 
of  volatile  oil,  I  think  the  first  alcoholic  or  ethereo-alcoholic  tinc- 
ture may  be  safely  evaporated  at  a  moderate  heat  of  about  160° 
F.,  without  any  appreciable  loss  of  volatile  oil.  The  volatile 
principle  of  black  snakeroot,  a  member  of  the  family  of  Ranun- 
culacege,  is  probably  of  a  nature  similar  to  the  volatile  acrid  prin- 
ciples found  in  the  roots  of  some  other  plants  belonging  to  this 
important  family,  and  which  mostly  are  of  such  a  delicate  nature 
as  to  be  easily  modified  or  completely  changed  by  the  influence 
of  air,  so  that  it  most  likely  will  be  found  essential  to  prepare 
the  fluid  extract,  not  only  from  the  recently  dried  root,  but  also 
to  hasten  the  first  part  of  the  process  in  order  to  bring  this 
principle  under  the  protecting  agency  of  sugar. 
With  properly  constructed  apparatus,  I  am  of  opinion  that 
exhaustion  of  the  crude  material  with  ether  may  be  found  pre- 
ferable, as  the  ether  allows  of  its  evaporation  being  carried  on 
at  a  very  moderate  temperature,  and  might  be  nearly  all  regained, 
while  the  resulting  extract  may  be  taken  up  by  alcohol,  which 
would  leave  any  fixed  oil  and  much  of  the  chlorophylle  behind, 
