580 
Lithium  Bicarbonate. 
/Am.  Jour.  Pbarm. 
\   December,  1900. 
preservation,  the  percentage  of  alcohol  could  be  slightly  increased 
in  the  new  Tinctura  Opii  Deodorati.  If  I  may  be  permitted,  I 
would  respectfully  suggest  this  proposition  to  pharmacists  for  gen- 
eral consideration. 
A  little  point  arising  from  working  details  may  be  of  value  to 
pharmacists.  Granulated  opium  is  far  superior  to  powdered  opium 
for  making  any  of  its  preparations  by  percolation,  its  use  doing  away 
with  many  of  the  troubles  of  percolating  a  powdered  drug  that  will 
gum  in  spite  of  the  addition  of  sand,  calcium  phosphate,  etc. 
Opium  in  this  form  can  be  purchased  in  the  open  market,  but  the 
pharmacist  can  easily  prepare  it  for  himself  by  cutting  the  crude 
drug  into  thin  slices,  drying  these  thoroughly  and  grating  the  crisp 
slices  through  a  very  coarse  wire  sieve.  This,  I  believe,  is  the  basis 
of  the  method  of  the  manufacturers.  Of  course,  an  assay  must  be 
made  of  the  granulated  opium,  as  the  drug  will  lose  much  moisture 
and  weight  in  drying  and  increase  in  strength  thereby. 
LITHIUM  BICARBONATE. 
By  Lyman  F.  Kebi^er. 
For  some  time  past  repeated  inquiries  have  come  for  lithium  bi- 
carbonate, and  certain  manufacturers  are  supplying  an  article  which 
they  call  by  this  name.  Theoretically  it  is  possible  for  this  chemi- 
cal to  exist,  but  thus  far,  so  far  as  the  writer  knows,  it  has  never 
been  prepared,  except  in  solution.  Being  anxious  to  know  whether 
some  one  had  really  succeeded  in  preparing  lithium  bicarbonate,  the 
writer  secured  a  sample  and  made  a  careful  analysis.  It  consisted 
of  white  crystalline  crusts.  One  part  of  the  finely  powdered  chemi- 
cal required  75  parts  of  distilled  water,  at  150  C,  for  solution.  The 
solution  is  alkaline  to  litmus.  On  heating  a  given  weight  to  200°  C. 
for  some  time,  there  was  a  loss  of  0-29  per  cent.;  farther  heating  to 
fusion  increased  the  loss  only  slightly.  On  intimately  mixing  one 
part  of  the  finely  powdered  article  with  twice  its  weight  of  pure 
powdered  ammonium  sulphate  and  igniting  there  will  be  left 
lithium  sulphate.  By  this  process  the  article  contained  98-39  per 
cent,  of  lithium  carbonate.  This  method  includes  as  lithium  the 
inorganic  incidental  impurities  of  which  traces  are  present. 
By  the  acidimetric  method  the  sample  contains  97-97  per  cent,  of 
