Am.  Jour.  Pharm,"> 
July,  18S9.  > 
Manufacture  of  Chloroform. 
323 
shown  in  Fig.  1,  it  is  done  in  a  series  of  three  slightly-inclined 
cylindrical  retorts,  in  which  the  material  is  continually  pushed 
forward  by  revolving  blades.  The  crude  gray  acetate  is  dropped  in 
at  a  and  passes  along  the  length  of  the  upper  retort  until  it  drops 
upon  the  blades  which  revolve  in  the  second  retort,  and  passing  along 
this  is  dropped  into  the  third  or  lowest  retort,  from  which  it  issues  at  g, 
and  is  collected  in  suitable  vessels.  As  seen  in  the  illustration,  the  in- 
clination of  these  three  retorts  is  different,  so  that  the  material  passes 
along;  most  rapidly  as  it  descends  into  the  hottest  retort  below.  At  e 
and  /  are  connections  with  the  flue,  through  which  the  moisture  and 
Fig.  1. 
tarry  vapors  can  pass  off.  By  this  continuous  roasting  process,  the 
crude  material  can  be  purified  without  notable  decomposition  of  the 
true  acetate.  The  second  patent,  No.  385,777,  issued  to  the  same 
aud  assigned  to  the  same,  refers  to  the  method  of  distilling  the 
roasted  gray  acetate.  Here,  to  secure  the  maximum  yield  of  acetone, 
the  points  to  be  attained  are  uniformity  of  temperature  throughout 
the  whole  mass  and  slow  heating  to  not  over  300°  C.  The  patentee 
claims  that  "  in  the  process  of  subjecting  acetates  in  a  closed  vessel  to 
heat  applied  externally  to  the  vessel  for  distilling  acetoue  from  the 
acetates,  the  desired  slowness  and  uniformity  of  temperature  may  be 
