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NITROGLUCOSE. 
An  attempt  to  prepare  nitroglucose  by  the  use  of  nitre  and 
sulphuric  acid,  which  succeeds  so  well  and  so  easily  in  the  case 
of  cellulose,  failed  almost  wholly  with  sugar.  Not  more  than 
two  or  three  per  cent,  of  the  weight  of  the  sugar  was  obtained. 
With  sulphuric  and  strong  nitric  acids,  allowed  to  cool  tho- 
roughly after  mixing,  the  reaction  takes  place  easily,  and  a  con- 
siderable quantity  of  nitroglucose  is  obtained.  The  nitric  acid 
should  be  as  strong  as  possible,  and  as  the  acid  of  the  requisite 
strength  is  not  easily  obtained  commercially,  I  have  found  an 
advantage  in  using  in  part  the  fuming  sulphuric  acid.  Two 
fluidounces  of  fuming  sulphuric  acid,  two  of  common  sulphuric, 
two  of  strong  nitric  acid,  as  near  to  1*5  sp.  gr.  as  can  be  ob- 
tained, give  good  results.  The  sugar  is  stirred  in,  in  the  form 
of  powder,  to  a  thin  paste.  The  stirring  is  kept  up,  and  as 
fast  as  the  nitroglucose  separates  in  doughy  masses,  it  is  re- 
moved with  a  spatula  and  thrown  into  cold  water.  A  further 
addition  of  sugar  will  give  more  nitroglucose,  but  considerably 
less  in  proportion  than  the  first  edition.  As  soon  as  possible, 
the  nitroglucose  is  to  be  kneaded  up  with  cold  water,  to  get 
the  acid  out.  In  one  case  when  this  was  neglected,  for  ten  or 
fifteen  minutes,  the  nitroglucose  passed  to  a  greenish  color  and 
apparently  was  undergoing  a  commencing  decomposition. 
The  removal  of  the  adhering  acid  is  much  more  difficult  than 
in  the  case  of  pyroxylin,  and  is  an  extremely  disagreeable  opera- 
tion. The  acid  pervades  the  whole  of  the  doughy  mass  so 
fully  that  the  fingers  are  stained  and  burned  by  it,  nor  can  the 
whole  of  the  acid  be  removed  satisfactorily  in  this  way.  The 
best  means  I  found  was  to  dissolve  the  crude  nitroglucose  in  a 
mixture  of  alcohol  and  ether  and  then  to  pour  this  into  a 
large  quantity  of  cold  water  with  constant  stirring,  and  violent 
agitation  afterward.  The  method  is  not  altogether  satisfactory, 
and  seems  to  be  attended  with  some  loss  of  material,  though 
why,  it  is  not  easy  to  see. 
Prepared  in  this  way,  nitroglucose  is  a  white  lustrous  body, 
which  may  either  assume  the  doughy  amorphous  condition  or 
the  crystalline,  and^  passes  from  one  to  the  other  with  extreme 
ease.  When  first  formed  by  the  mixed  acids,  it  always  has  the 
doughy  form.    That  which  I  obtained  by  the  use  of  nitric  and 
