158  Acetone  and  Acetone-Chloroform.  {^'-dlxk^i^1 
to  1,400  pounds  of  35  per  cent,  bleaching  powder,  1  to  5 — to  pass 
the  resulting  chloroform  through  scrubbers,  then  distil  it  through 
water — then  distil  it  from  a  small  portion  of  bleaching  powder — 
then  pass  it  through  sulphuric  acid  scrubbers,  and  finally  rectify  it 
in  three  fractions,  the  large  middle  fraction  being  accepted,  and  the 
others  being  worked  over. 
A  part  of  the  great  excess  of  acetone  taken  in  the  1  to  5  propor- 
tion is  recovered  by  continuing  the  distillation  after  the  chloroform 
is  all  over.  Another  part  is  recovered  in  the  wash  water  from  the 
scrubbers  and  the  distillation,  and  the  small  remainder  is  decom- 
posed by  the  small  proportion  of  bleaching  powder,  the  total  amount 
recovered  being  practically  not  far  from  the  total  excess. 
To  this  recovered  acetone,  carefully  assayed,  new  acetone  is  added 
to  make  up  the  280  pounds  for  the  next  charge. 
The  patentees  were  invited  to  see  this  apparatus  and  process  in 
order  to  convince  them  that  there  is  a  strong  desire  to  avoid  any 
color  of  infringement,  by  taking  the  Siemerling  proportions  which 
are  excluded  from  their  patent.  But  they  took  the  ground  that  this 
was  a  mere  evasion,  or  getting  round  their  patent  by  using  the  ex- 
cess of  acetone  over  again,  and  could  not  be  made  to  see  that  this, 
if  objectionable,  is  so  by  defect  in  the  equity  of  the  patent,  and  is  a 
proceeding  that  antedated  the  patent  by  many  years.  And  finally,, 
they  covered  everything  by  claiming  that  the  patent  secured  to  them 
the  sole  right  to  make  chloroform  from  acetone  in  the  United  States, 
thus  claiming  a  reaction  that  had  been  well  known  for  more  than 
fifty  years. 
As  to  the  reasons  why  large  manufacturers  of  chloroform  did  not 
avail  themselves  earlier  of  the  acetone  process,  the  first  answer  is 
that  it  is  probable  that  many  of  them,  in  Germany,  at  least,  did  so 
secretly  as  soon  as  acetone  became  cheaper  than  alcohol. 
But  as  to  other  more  positive  reasons,  the  writer,  as  having  been 
for  many  years  a  large  manufacturer  from  alcohol,  and  as  having, 
with  all  other  makers,  given  up  the  manufacture  rather  than  con- 
test this  patent,  can  only  speak  for  himself.  He  for  many  years 
doubted  the  identity  of  alcohol  and  acetone-chloroform,  and  doubted 
whether  the  latter  was  as  easily  purified  for  use  as  the  former,  so 
that  when  chloroform  was  offered  to  him  at  so  low  a  price  as  to  in- 
sure that  it  was  made  from  acetone  it  was  refused.  Chloroform  has 
always  been  a  most  important  agent,  and  during  the  early  part  of 
