'^"•iviri8^8o"'"-}  Chemical  Notes.  ,         26  j 
was  taken,  great  difficulty  was  experienced  in  getting  satisfactory  deter- 
minations, owing  to  its  volatility.  The  results  agreed  in  general  with 
those  of  Craft's.  When  the  bromine  was  liberated  in  the  nascent 
state  from  platinic  bromide,  PbBr^,  they  got  results  agreeing  exacdy 
with  I  Br2,  showing  dissociation.  They  say  nothing  as  yet  of  the 
nature  of  the  dissociation  products  of  the  three  halogens.  —  Nature^ 
March  i8th,  1880,  p.  461. 
Manufacture  of  Glauber  s  Salt  in  the  south  of  France. — The  following 
interesting  description  of  the  extraction  of  Glauber's  salt  from  the  sea- 
brines,  as  now  practiced  at  the  large  salines  at  the  mouth  of  the  Rhone 
River,  contains  several  items  of  interest  to  the  chemist. 
The  sodium  sulphate  is  obtained  by  decomposing  a  liquor  which 
contains  common  salt  and  magnesium  sulphate  in  proper  proportions 
by  the  aid  of  artificial  cold.  The  Carre  ice  machine  is  used  for  this 
purpose.  The  crude  material,  the  sel  mixte^  crystallizes  out  at  a  cer- 
tain stage  in  the  evaporation  of  the  mother-liquor  left  after  common 
salt  has  crystallized.  This  special  liquor  is  then  cooled  by  an  ingenious 
application  of  the  refrigerating  process  until  — 6°C.  is  reached,  when 
Glauber's  salt  separates  out  as  a  crystalline  scum,  which  is  removed 
and  carried  by  elevators  to  large  draining  casks.  Here  the  salt  is  freed 
from  adhering  water  and  is  now  ready  to  be  made  anhydrous.  This 
operation  had  given  great  difficulty,  as  the  evaporation  in  iron  pans  was 
not  possible,  on  account  of  the  tendency  of  the  separating  anhydrous 
sulphate  to  burn,  and  calcination  with  the  aid  of  a  reverberatory  flame 
was  also  extremely  difficult  to  carry  out.  The  difficulty  has  been 
overcome  very  simply.  The  water  of  crystallization  is  not  driven  ofF 
by  heat,  but  is  displaced.  For  this  purpose  the  crystallized  Glauber's 
salt,  in  quantities  of  1,500  kilograms,  is  fused  with  a  small  amount 
of  the  mother-liquor  in  a  wooden  tank  heated  by  a  copper  worm  and 
provided  with  stirrers,  when  250  kilos  of  common  salt  are  added.  In 
the  degree  that  the  salt  dissolves,  anhydrous  Glauber's  salt  is  precipi- 
tated, and  at  the  end  of  the  operation  about  85  per  cent,  of  the  Glau- 
ber's salt  originally  used  is  gotten  as  an  anhydrous  precipitate.  The 
salt  so  obtained  has  at  most  0  5  per  cent,  sodium  chloride  and  5  per 
cent,  of  water  present. — Chem.  Industrie^  Jan.  1880,  p.  9. 
Organic  Chemistry. — Extraction  of  Fresh  Flower  Perfumes  zvith 
Methyl  Chloride.- — C.  Vincent,  who  has  prepared  methyl  chloride 
recently  in  such  large  amount  from  the  residues  of  beet-root  molasses 
(this  Journal,  March,  1879,  p.  126)  has  made  exper/ments  on  a  large 
