310  Epinephrin  and  its  Compounds.  {Amjiuy,ri903.arm" 
whatsoever  is  deducible  from  the  above  analytic  data,  a  sure  indi- 
cation that  adrenalin,  as  hitherto  isolated,  is  a  mixture  and  not  a 
chemical  individual.  The  fact  that  adrenalin  is  so  readily  converti- 
ble into  the  alkaloidal  modification  suggests  at  once  that  a  simple 
relationship  must  exist  between  these  two  modifications  of  the  blood- 
pressure-raising  principle,  quite  aside  from  the  question  as  to 
whether  an  atomic  rearrangement  has  occurred  in  the  process  of 
conversion. 
ON    THE    TRUE    ELEMENTARY   COMPOSITION  OF  THE  ABOVE-DESCRIBED 
CRYSTALLINE,  NON- ALKALOIDAL  FORM  OF  EPINEPHRIN. 
Since  neither  Aldrich  nor  Takamine  has  succeeded  in  isolating 
adrenalin  as  a  pure  substance,  and  also  because  it  is  necessary  to 
establish  the  relationship  existing  between  epinephrin  and  this  sub- 
stance, I  have  undertaken  to  purify  and  to  analyze  it.  As  prepared 
by  the  zinc-ammonia  process  described  by  me  in  an  earlier  paper,1 
and  washed  entirely  free  of  ammonia  with  water,  alcohol  and  ether 
and  then  dried  in  vacuo  over  sulphuric  acid,  adrenalin  is  found  to 
be  stable  as  long  as  it  is  kept  perfectly  dry.  As  made  by  me 
according  to  the  process  just  named,  redissolved  in  dilute  hydro- 
chloric acid  and  again  precipitated  with  ammonia,  its  composition 
was  found  to  be: 
C  =  57"39  to  57-60 
H  =  6*29  to  677 
N  =  7*38  (Kjeldahl-Gunning). 
After  nine  precipitations  with  ammonia  or  sodium  carbonate  its 
composition  changed  to: 
I.  II.  Required  for  C10Hi3NO3  .  ^H20. 
C  =  58-61      58-67  C  =  58-82 
H—  6-84       6-77  H=  6-86 
N=   7-08  (Kjeldahl-Gunning2)  N  =  6'86 
O  =  27-47  O  =  27-46 
1  The  Johns  Hopkins  Hospital  Bulletin,  February-March,  1902,  Vol.  XIII. 
2  In  applying  this  method  it  is  necessary  to  continue  the  digestion  with  the  con- 
centrated sulphuric  acid  for  about  four  hours  in  order  to  effect  the  complete  de- 
composition of  the  substance.  I  was  for  a  time  of  the  opinion  that  the  Kjeldahl- 
Gunning  method  does  not  liberate  all  of  the  nitrogen  as  ammonia  (see  Amer. 
four,  of  Physiology,  Vol.  VIII,  1903,  No.  5),  but  it  was  afterwards  found  that 
the  control  analysis  by  the  method  of  Dumas  was  at  fault. 
