368  The  Direct  Synthesis  of  Ammonia.   {A  Au^i  i™' 
determined  to  make  trial  of  the  bromide  of  zinc,  and  accordingly  gave 
the  patient  15  drops  of  the  glycerole,  properly  diluted,  three  times  a 
day- — which  dose  was  afterwards  increased  to  20  drops.  After  a  few 
days'  use  of  the  remedy,  the  patient  returned  to  her  home  in  the 
country,  where  she  continued  to  take  it,  and  I  learned  at  second  hand 
from  her  physician  there,  that  her  condition  is  very  much  improved. 
Whether,  and  to  what  extent,  the  dose  may  have  been  increased,  I 
am  not  informed.  Of  course,  we  can  only  determine  by  repeated  and 
cautious  trials  what  dose  can  be  safely  tolerated,  and  what  quantity 
must  be  given  to  ensure  its  favorable  therapeutic  action.  To  obviate 
any  possible  irritating  effect  upon  the  alimentary  canal,  the  medicine 
ought  to  be  given  in  a  sufficient  quantity  of  water,  to  which,  if  desir- 
able, mucilage  and  aromatics  might  be  added. 
If  any  of  your  readers  should  decide  to  make  trial  of  the  remedy 
here  suggested  (which  can  now  be  obtained  of  several  of  our  apothe- 
caries), I  hope  the  results,  whether  good  or  bad,  will  be  duly  commu- 
nicated for  the  general  information.        Yours  very  truly, 
L.  S.  Joynes,  M.D. 
—  Virginia  Clinical  Record,  July,  1873. 
THE  DIRECT  SYNTHESIS  OF  AMMONIA* 
By  W.  F.  Donkin. 
The  action  of  induced  electricity  on  mixtures  of  certain  gases  has 
been  lately  shown  by  Sir  Benjamin  Brodief  to  yield  very  interesting 
results.  • 
An  obvious  application  of  his  method  was  to  treat  a  mixture  of  dry 
hydrogen  and  nitrpgen  in  a  similar  manner  as  those  referred  to  above, 
with  the  view  of  effecting  the  synthesis  of  ammonia  ;  and  Sir  B.  Brodie 
kindly  allowed  me  the  use  of  his  apparatus  for  the  purpose  of  the  ex- 
periment, which  was  conducted  as  follows  : 
A  mixture  of  about  three  volumes  of  hydrogen  with  one  of  nitro- 
gen in  a  bell-jar  over  water,  was  passed  through  two  tubes'  containing 
pumice  moistened  with  ajkaline  pyrogallate  and  sulphuric  acid  re- 
spectively, then  through  a  Siemens  induction-tube,  and  into  a  bulb 
containing  dilute  hydrochloric  acid.    The  whole  apparatus  being  first 
*  Read  before  the  Royal  Society,  May  1,  1873  (Proceedings,  vol.  xxi,  p.  281). 
t  Proceedings  of  Royal  Society,  April  3,  1873,  and  Pkarm.  Joum.,  3d  series, 
vol.  iii,  pp.  136,  156. 
