Am.  Jour.  Pharm.  \ 
January,  1915.  j 
Oxidation  of  Nitrogen. 
29 
THE  OXIDATION  OF  NITROGEN  AND   HOW  CHEAP 
NITRATES  WOULD  REVOLUTIONIZE  OUR 
ECONOMIC  LIFE.1 
By  Dr.  W.  W.  Strong. 
How  is  Atmospheric  Nitrogen  Oxidized  ? 
It  is  not  many  years  ago  ( 1898)  that  Sir  William  Crookes  sounded 
the  note  of  alarm  concerning  the  possibility  of  a  future  famine  in 
the  world's  supply  of  nitrates  and  other  nitrogen  compounds.  At 
that  time  the  supply  of  these  salts  was  largely  confined  to  certain  beds 
of  guano  and  Chile  saltpetre.  During  the  past  few  years  most  im- 
portant advances  have  been  made  in  our  knowledge  of  the  fixation 
of  atmospheric  nitrogen,  and  some  of  the  processes  have  been  placed 
upon  a  purely  commercial  basis. 
In  addition  to  drawing  on  the  air  directly  for  nitrogen  it  has  been 
found  that  large  amounts  of  ammonia  and  other  nitrogen  compounds 
may  be  obtained  as  by-products  from  coal  and.  peat  in  connection  with 
the  manufacture  of  coke,  illuminating^  gas,  and  the  metallurgy  of 
iron.  The  treatment  of  various  shales,  peats,  silts,  and  organic  refuse 
often  yields  nitrogen  compounds.  The  nitrogen  in  these  substances 
has  probably  been  derived  from  the  atmosphere  by  one  or  more  of  the 
processes  which  will  now  be  described. 
The  amount  of  nitrogen  that  enters  into  the  plant  and  animal 
growth  ("nomadic"  nitrogen)  has  been  estimated  to  be  about  20 
Gms.  per  square  yard  of  land.  Part  of  this  is  being  constantly 
changed  into  nitrogen  gas  by  the  action  of  nitrifying  and  denitrifying 
bacteria.  In  nature  an  equilibrium  is  maintained  between  the  action 
of  these  bacteria  and  the  oxidization  of  nitrogen  in  the  air  by  means 
of  electrical  discharges  and  the  action  of  plants,  such  as  clover.  The 
natural  processes  of  fixing  nitrogen  are  therefore  electrical  and  by  the 
action  of  bacteria  in  the  legume  crops  of  clover  and  similar  plants. 
In  former  geological  times  certain  nitride  and  other  chemical  com- 
pounds may  have  been  formed  directly  with  the  air  nitrogen,  but  it  is 
doubtful  if  any  such  direct  chemical  reactions  take  place  at  present. 
The  natural  oxidation  of  nitrogen  by  electrical  discharges  takes 
place  during  electrical  storms,  the  aurora  discharges  at  high  levels, 
1  Reprinted  from  Science,  Dec.  18,  1914. 
