292 
Varieties. 
f  Am.  Jour.  Pharm. 
t    June  1, 1874. 
commercial  iodine  is  often  considerable,  frequently  as  much  as  20  per 
cent.  This  must  be  determined  by  difference,  as  all  direct  determi- 
nations being  attended  by  heat  would  cause  large  quantities  of  iodine 
to  volatilize. 
We  have,  however,  in  cases  where  the  sample  is  very  moist,  em- 
ployed the  following  method  :  Place  a  gramme  of  iodine  in  a  narrow 
tube  graduated  into  tenths  of  centimetres,  add  20  c.  c.  of  bisulphide 
of  carbon,  and  shake  the  tube.  Closing  the  orifice  with  the  finger, 
till  the  iodine  is  entirely  dissolved,  cork  the  tube,  and  allow  it  to 
stand  in  a  warm  place  for  three  hours  ;  at  the  end  of  the  time  the 
water  in  the  iodine  will  have  separated  from  the  solution,  and  the 
number  of  centimetres  occupied  by  the  water  will  give  the  percentage 
contained  in  the  iodine.  This  method  is  not  exact,  but  will  act  as  a 
check  upon  the  remainder  of  the  analysis. 
Below  are  a  number  of  analyses  of  commercial  iodine,  Nos.  3,  4, 
and  5  being  good  samples ;  Nos.  1  and  2  containing  more  water  than 
is  usually  found. 
1 
2 
3 
4 
5 
Iodine, 
.  76-21 
79-50 
84-25 
88-61 
94-12 
Chlorine, 
0-88 
0-71 
0-92 
0-52 
0-30 
Ash,  . 
1-11 
1-02 
0-80 
0-72 
0.40 
Moisture, 
21-80 
18-77 
14-03 
10-15 
5-18 
100-00 
100-00 
100-00 
100-00 
100-00 
- — Amer.  Chemist,  May,  1874. 
ututm. 
The  Product-ion  of  Vanilla. — In  the  island  of  Reunion  (or  Bourbon)  there 
were  in  1870  nearly  700  acres  under  culture  with  vanilla,  which  produced 
37,024  lbs.  The  French  Colonial  Commission  has  been  seeking  to  extend  the 
culture  of  this  valuable  orchid.  It  appears  that  the  large  sales  of  vanilla  which 
were  made  in  the  French  Colonial  Section  of  the  Paris  Exhibition,  in  1867,  have 
extended  the  taste  for  this  aromatic  flavoring,  and  caused  the  price  of  the  finest 
qualities  of  Reunion  Vanilla  to  advance  from  16  francs  to  100  francs  per  lb. 
In  view  of  the  insufficiency  of  the  production  to  meet  the  increased  demand, 
instructions  have  been  sent  out  to  these  colonies  as  to  the  processes  of  arti- 
ficially fecundating  and  preparing  the  pods,  and  it  is  expected  that  the  culture 
will  be  largely  extended.  It  was  from  Reunion  that  this  orchidaceous  plant  was 
transported  to  Mauritius,  by  M.  Richard,  of  the  Botanic  Garden  of  Reunion. 
The  plantations  for  vanilla  are  extending  in  Mauritius,  and  occupy  the  atten- 
tion of  many  small  proprietors.    This  product  bids  fair  to  extend  considerably, 
