372 
Polarization  by  Mixtures. 
( Am.  Jour.  Pharm. 
\     August,  1901. 
bottles  covered  with  perforated  paper  answered  the  purpose  very 
well,  and  in  the  results  which  follow,  the  short  tube  belonging  to 
the  saccharimeter  was  used  with  a  bottle  containing  the  second 
liquid.  The  next  tube  shows  the  result  of  comparing  the  separate 
and  combined  effects  of  various  oils. 
TABLE  IV. 
Number  and  Name  of  Substance. 
Rotation 
Observed. 
Rotation 
Computed. 
Percent,  of 
Deviation. 
No.  i,  turpentine. 
-6°-3o 
No.  2,  mixture  of  turpentine  and  orange. 
64°-42 
No.  3,  orange  oil. 
240-94 
No.  4,  mixture  of  nutmeg,  orange  and  mint. 
i7°6o 
No.  5.  orange  oil  (small  bottle). 
i3°-55 
No.  6,  mixture  of  nutmeg,  orange  and\ 
mint  (small  bottle).  J 
9°"43 
Nos.  1  and  3. 
i8°72 
i8°64 
0-3 
Nos.  1  and  5. 
7°-i6 
7°*25 
0-4 
Nos.  2  and  4. 
8i°-97 
82°'02 
O'l 
Nos.  2  and  6. 
730,39 
73°85 
0-6 
In  order  to  determine  whether  two  substances  mixed  together 
would  give  the  sum  of  the  rotations  due  to  the  ingredients  sepa- 
rately, solutions  of  the  various  sugars  were  placed  in  the  double 
tube,  and  results  reached  as  follow : 
TABLE  V. 
Substance. 
Rotation 
Observed. 
Rotation 
Calculated. 
Per  Cent,  of 
Deviation. 
Tube  1,  grape  sugar. 
7°"99 
Tube  2,  cane  sugar. 
I7°79 
Mixture. 
i2°-85 
i2°-89 
o-3 
The  calculated  rotation  was  obtained  by  remembering  that  the 
relative  lengths  of  the  parts  of  the  double  tube  were  I  :  1-002. 
12^  X  7°-99  =  4°-oo7 
2  002 
X  I7°'79  =  8°.886 
2  002 
40-007  +  8°-886  =  i2°-89 
