418 
Pyridine. 
Am.  J*ur.  Pharm, 
Aug.,  1888. 
Saturated  Solution  of  Mercuric  Chloride. — One  cc.  of  reagent  and 
2  cc.  of  solution  give  a  white  precipitate  dissolved  by  heat. 
Concentrated  Solution  of  Stannous  Chloride. — Yellowish  coloration. 
Concentrated  Hydrochloric  Acid. — According  to  several  authors,  if 
to  2  cc.  of  solution  of  antipyrin  two  drops  of  fuming  hydrochloric 
acid  be  added  the  mixture  is  colored  green,  and  changes  to  red  if  it  be 
heated  and  a  drop  or  two  more  of  the  acid  be  added.  We  have  not 
been  able  to  obtain  any  such  reaction. 
Antipyrin  is  consequently  sufficiently  characterized  by  the  form  of 
the  crystals,  the  melting  point  of  the  dried  substance  and  the  fore- 
going reactions. 
We  have  recognized  that  antipyrin  resists  the  most  energetic  chemi- 
cal agents.  Blumenbach  has  shown  that  it  resists  the  agents  of 
putrefaction,  and  we  have  ourselves  found  it  intact  in  urine  that  had 
been  in  full  putrefaction  for  eight  days.  AVe  have,  on  the  other 
hand  recognized  that  an  aqueous  solution  of  antipyrin  is  unsuitable 
to  the  development  of  inferior  organisms,  such  as  the  fungi  that 
attack  the  solutions  of  most  of  the  alkaloids. 
PYRIDINE. 
By  D.  J.  Leech. 
Pyridine  (C5H5  N)  is  a  volatile  colorless  liquid,  with  a  strong  odor 
and  a  burning  taste,  produced  during  the  dry  distillation  of  many 
forms  of  organic  matter.  It  is  present  in  animal  oil  (DippePs)  made 
by  distilling  bones,  and  also  in  coal  tar ;  it  is  formed,  too,  during  the 
combustion  of  tobacco,  and  probably  during  the  burning  of  nitre 
paper  and  several  other  organic  substances,  the  fumes  of  which  are 
used  for  the  relief  of  asthma.  Harnach  and  Meyer^s  experiments^  led 
them  to  look  upon  it  as  a  stimulant  of  the  motor  centres  and  nerve 
endings.  Bochefontaine,^  on  the  other  hand,  found  it  to  be  a  local 
irritant,  though  after  introduction  into  the  system  it  causes  death  by 
paralysis.  See  regarded  it  as  a  depressor  of  the  reflex  irritability  of 
the  spinal  cord  and  respiratory  centre,  and  as  the  active  ingredient  of 
the  various  fumes  from  cigarettes,  medicated  papers,  etc.,  which  give 
1  Arch.f.  Path,  und  Phar.,  XII.,  395. 
2  Comp.  rend,  de  la  Soc.  de  Biol,  Ser.  VII.,  Tom.  III.,  p,  5. 
