352  Processes  and  Laboratory  Notes.      {^™' zZiylum™' 
Shake  vigorously,  and  allow  to  stand  for  six  hours  or  over  night, 
then  add  5  c.c.  10  per  cent,  ammonia  water,  shake  well  and  pour  off 
50  grammes  of  the  clear  solution  (representing  5  grammes  of  the 
white  hellebore).  Transfer  the  solution  to  a  separatory  funnel  and 
shake  out  the  alkaloid  with  acidulated  water,  using  three  fractions  of 
20  c.c.  each.  Place  the  aqueous  washings  in  a  separatory  funnel,  and, 
after  rendering  alkaline  with  ammonia  water,  shake  out  the  sepa- 
rated alkaloid  with  a  mixture  of  chloroform  3  volumes,  ether  1 
volume.  Transfer  these  washings  to  a  tared  flask,  recover  the 
solvent,  if  desired,  and  weigh  the  residue,  which  is  the  total  amount 
of  alkaloid  in  5  grammes  of  the  drug. 
The  results  shown  below  were  obtained  by  the  foregoing  process, 
using  the  commercial  drug  in  the  form  in  which  it  is  sold  for  an 
insecticide.    Five  different  samples  assayed  respectively  : 
No.  1,  1-20  per  cent.;  No.  2,  1-24  per  cent.;  No.  3,  1-25  per  cent.; 
No.  4,  i- 1 2  per  cent.;  No.  5,  118  per  cent,  alkaloids. 
A  sample  of  the  whole  drug  was  also  ground  and  assayed.  This 
yielded  1-75  per  cent. — a  somewhat  higher  yield,  which  should  be 
verified  by  assaying  numerous  different  samples  before  accepting  it 
as  a  standard.  The  results  as  obtained  show  the  commercial 
drug  to  be  uniform  and  about  I  per  cent,  would  be  a  fair  limit  for 
the  minimum  allowable  yield  of  alkaloids  by  this  process. 
ARE  C.  P.  CHEMICALS  CHEMICALLY  PURE? 
In  answer  to  query  No.  44,  requesting  information  upon  the  sub- 
ject, it  is  difficult  to  give  a  definite  reply.  The  term  Chemically 
Pure,  commonly  abbreviated  C.  P.,  is  used  with  such  frequency  when 
applied  to  inorganic  compounds,  that  it  loses  its  force  in  a  great 
degree.  To  comply  with  this  description  accurately,  a  chemical 
should  be  absolutely  free  from  all  foreign  compounds,  an  ideal 
requirement  seldom  found  in  practice.  As  generally  applied,  it  has 
come  to  mean  simply  a  very  high  degree  of  purity,  such  as  is  re- 
quired for  analytical  reagents,  and,  according  to  this  interpretation 
of  the  term,  the  quality  of  most  C.  P.  chemicals  sold,  is  in  accord- 
ance with  the  description.  As  an  illustration  of  this  accepted  mean- 
ing, sulphuric  acid  may  be  mentioned.  This  acid  is  listed  as  "  C.  P.," 
and  also  "  C.  P.,  free  from  arsenic."  The  latter  commands  the  higher 
price,  thus  indicating  a  degree  of  purity  higher  than  "  C  P." 
Some  cases  have  been  observed  in  which  the  term  was  clearly 
