IMPROVEMENTS  IN  THE  MANUFACTURE  OF  SUGAR.  361 
Assuming  the  specific  gravity  of  the  nitrous  ether  separated 
by  the  chloride  of  calcium  to  be  -899,  as  stated  by  the  Edin- 
burgh College,  or  -900  as  stated  in  the  Dublin  Pharmacopoeia  of 
1826,  the  proportion  of  nitrite  of  soda  directed  by  the  British 
Pharmacopoeia  should  yield,  if  pure,  a  spirit  of  nitrous  ether 
containing  17*25  per  cent.*  The  above  result,  13  per  cent., 
would  imply  a  percentage  of  nitrite  of  soda  in  the  salt  used  equal 
to  75-34, f  a  conclusion  which  has  been  further  confirmed  by  the 
amount  of  nitrogen  gas  evolved  by  decomposing  the  salt  with 
chloride  of  ammonium.  On  the  same  basis  of  calculation  it 
would  require  the  nitrite  of  soda  used  to  contain  55*07  per  cent, 
of  real  nitrite  in  order  to  produce  the  strength  specified  by  the 
British  Pharmacopoeia,  and  46-32  to  bring  the  mixture  of  spirit 
and  test  liquor  up  to  the  point  of  saturation,  or  8-  per  cent. J 
Since  the  appearance  of  the  British  Pharmacopoeia,  I  have 
again  procured  samples  of  spirits  of  nitre  from  several  of  our 
leading  manufacturers,  but  in  no  case  have  I  yet  found  sufficient 
nitrous  ether  present  to  yield  any  indication  by  the  test.  In 
fact,  it  has  been  admitted  that  a  salt  containing  25  per  cent,  of 
real  nitrite  is  the  best  product  that  has  been  obtained  by  the 
process  of  deflagration. 
Apothecaries'  Hall,  Blackfriars,  June,  1865. 
— London  Pharm.  Jour.,  July,  1865. 
IMPROVEMENTS  IN  THE  MANUFACTURE  OF  SUGAR. 
A  correspondent  writes : — u  I  have  seen  some  sugar  from 
Antigua  which  is  the  result  of  a  new  mode  of  boiling  down. 
This  sugar  is  in  reality  only  boiled  down  juice,  and  yet  is  so  dry 
*  NaO,NO  3  fEO,N03  by  Weight.    By  Vol. 
69      :  75    :  :  5  :  5-435 
 =      .6*04    in  35  of  spirit  of  nitrous 
•900 
ether  =  17*25  per  cent.  Nitrous  Ether. 
Vol.  wt. 
fThus:— 17*25  :  100  :  :  13  : 75-34;  or,  100  :  13  :  :  35  :  4*55-h*900=4*095. 
Then,  75  :  69  :  :  4*095  :  3.767  +  20  =  75*34. 
t  And  )  9*5  4-  100 
[  =  55*07. 
B.P.I  17*25 
