556  PRESERVATION  OF  MEDICINAL  PREPARATIONS. 
conii,  hyoscyami,  and  ergotse.  Alcoholic  and  ethereal  extracts 
likewise  do  not  require  this  treatment ;  but  it  would  do  no  harm 
and  certainly  prevent  changes,  unknown  to  us,  which  may  take 
place  in  the  course  of  years. 
5. — Tinctures. 
Tinct.  rhei  aquosa,  filled  in  1  oz.  vials  and  treated  by  Appert's 
method,  keeps  unaltered ;  carbonate  of  soda  produces  a  much 
finer  color  than  carbonate  of  potassa.  The  alcoholic  tinctures 
deposit  precipitates ;  sometimes  crystals,  like  tinct.  assafoetidse, 
castorei  and  scillse.  Tinct.  capsici,  after  having  been  exposed  to 
the  sunlight  (direct  ?)  for  eight  years,  had  lost  its  color  and 
acrimony ;  while  tinct.  colchici  and  colocynth.  showed  no  such 
change,  It  is  worthy  of  inquiry  how  the  various  liquid  medicines 
will  keep,  in  bottles  of  different  colors,  when  exposed  to 
diffused  and  direct  sunlight. 
6. — Roots,  Barks,  Herbs,  Flowers,  Seeds. 
The  advantage  of  double-cased  tin  vessels  for  the  preservation 
of  vegetables,  is  now  generally  admitted ;  when  entirely  dry 
they  keep  perfect  in  these  vessels.  Mullein  flowers,  after  eight 
years,  still  had  their  golden  yellow  color ;  narcotic  herbs,  after 
four  years,  their  peculiar  odor  and  green  appearance ;  burdock, 
Colombo,  chicory  and  elecampane,  after  five  years,  all  their 
sensible  properties,  and  no  insects  could  be  discovered. 
Ergot  and  mustard  flour  assume,  when  kept  in  this  manner,  a 
musty  odor  ;  but  such  mustard  was  just  as  strong  to  the  taste  as 
before ;  and  ergot,  when  treated  with  potassa,  evolved  a  fishy 
odor  not  less  faint  than  before.  It  appears,  however,  advisable 
not  to  keep  too  large  a  quantity  of  these  powders  on  hand. 
Vegetables  may  be  kept  in  glass  bottles,  when  they,  in  a  well 
dried  state,  are  treated  by  Appert's  method.  Violets,  roses, 
primroses  and  many  others  are  thus  preserved  in  an  excellent 
state. 
By  the  experience  of  the  pharmaceutist,  Liebig's  assertions 
are  proved,  namely  :  "  That  the  tendency  of  organic  matter  in 
contact  with  air  to  pass  into  fermentation  and  decay,  and  in 
consequence  thereof  to  start  fermentation  and  decay  in  others, 
is  suspended  without  exception  by  the  temperature  of  boiling 
water;  that  if  the  first  and  sole  cause  of  these  changes — 
