*"'^L°y:•Z""' }  Ethyl  Bromide.  243 
-and  perhaps  yet.  The  potassic  bromide  at  68,  the  sulphuric  acid  at 
15,  and  the  alcohol  at  30  cents,  will  make  the  expense  for  material  per 
^pound  only  90  cents,  while  any  young  man  can  make  this  amount  in 
two  hours'  time,  besides  attending  to  his  various  other  duties,  and  it 
will  enable  him  to  emancipate  himself  from  the  manufacturing  chemist, 
adding  by  it  to  his  self-esteem  and  the  elevation  of  his  profession. 
But  when  larger  quantities  are  'required,  and  when  it  is  a  matter  of 
importance  to  reduce  the  price  as  much  as  possible,  I  have  found  it  to 
advantage  to  deviate  from  the  above  process,  which,  however,  to  the 
.pharmacist  may  prove  most  suitable  for  its  preparation  on  a  small  scale. 
As  the  first  step  in  the  manufacture  of  potassic  bromide  is  that  of 
ferrous  bromide,  I  made  use  of  the  latter  at  once  to  obtain  the  desired 
ethyl  in  the  following  manner  : 
In  a  stone  jug  containing  about  i  gallon  of  water  and  pounds  of  iron 
turnings  or  wire,  5  pounds  of  bromine  are  gradually  added,  care  being 
taken  not  to  allow  the  temperature  to  rise  too  high,  the  jug  besides 
being  placed  in  cold  or  iced  water,  and  as  soon  as  the  reaction  has 
ceased  the  solution  of  the  green  ferrous  bromide  is  filtered  off,  the 
remaining  iron  being  well  washed  out  with  warm  or  boiling  water,  and 
to  it,  in  a  leaden  or  glass  flask  (I  have  found  the  acid  globe  of  a  carboy 
a  most  useful  vessel),  15  pounds  of  commercial  sulphuric  acid  are 
added  ;  after  the  mixture  has  sufficiently  cooled,  6  pints  of  alcohol 
(95  per  cent.)  are  intermixed,  the  mixture  well  agitated  and  distilled  at 
a  temperature  as  in  the  before-mentioned  operation.  I  have  in  this 
way  obtained  from  these  amounts  7  pounds  ethyl  bromide  at  a  cost  of 
material  of  not  over  $4.30,  or  about  60  cents  per  pound. 
Again,  in  this  reaction  the  chemistry  is  quite  simple,  the  sulphuric 
acid  uniting  with  the  iron  to  form  ferrous  sulphate,  while  the  two 
bromine  again  take  the  place  of  two  oxygen  in  the  two  ethyl  oxide,  the 
four  hydrogen  with  the  two  oxygen  of  the  ethyl  oxide  forming  two 
water,  and  may  be  expressed  in  symbols  as  follows  : 
FeBr^+iC^HgO  +  H^SO.^FeSO.-hiH^O  +  iC^H^Br. 
Although  the  ethyl  bromide  thus  obtained  is  by  far  purer  and  has 
less  odor  than  most  of  the  articles  found  in  the  market,  I  have  observed 
that,  on  evaporating  a  quantity  of  it,  it  left  a  heavy  acrid  odor  behind 
which  in  anaesthesia  was  bound  to  prove  objectionable  if  not  actually 
deleterious,  and  I  concluded,  therefore,  that,  after  washing,  I  would 
re-distill  it  at  a  low  temperature,  which  I  effected  by  placing  it  in  a 
gallon  bottle  contained  in  a  water-bath  and  connected  with  a  condenser. 
