552 
On  Tea. 
j  Am.  Jour.Phark. 
1     Dec.  1, 1873. 
Percentage  of  asK. 
Specimen  of  tea  used  by  myself,  .           .  5*63 
Civil  Service  tea,    .           .  .          .  5-56 
Horniman's  tea,           .           .  .  5*99 
Mandarin's  tea,  8s.  per  lb.,    '  .           .  5*30 
Orange  Pekoe,  5s.  per  lb.,       .  .          .  5*84 
"  .          .          .  6-06 
Green  tea,  4s.  6d.  per  lb.,        .  .           .  5*86 
Average,         .....  5*75 
These  determinations  were  made  on  tea  in  its  ordinary  air-dried 
condition,  and  agree  sufficiently  with  Zoller's.  The  proportion  of  ask 
in  absolutely  dry  tea  is  5*92  per  cent. 
Zoller  further  calls  attention  to  the  composition  of  the  ash  of  spent 
tea  leaves.  This,  as  might  be  expected,  is  far  less  rich  in  alkalies^ 
being  far  less  soluble.    Zoller's  analysis  is  as  follows  : — 
Potash,           .....  7-34 
Soda,       ......  0-69 
Magnesia,       .....  11*45 
Lime,       ......  10*76 
Oxide  of  iron,             ....  9*53 
Protoxide  of  manganese,  .  .  .  .  .  1*97 
Chlorine,         .....  trace 
Phosphoric  acid,    .....  25*41 
Sulphuric  acid,           ....  trace 
Silica,       ......  7*57 
Carbonic  acid,             ....  25*28 
100-00 
This  ash,  as  a  matter  almost  of  course,  must  be  composed  mainly 
of  material  insoluble  in  water. 
For  practical  purposes,  that  is  to  say  for  use  by  the  public  analysts, 
a  complete  analysis  of  the  ash  would  be  too  cumbrous  and  trouble- 
some. A  great  deal  of  information  may,  however,  be  gathered  from 
a  tolerably  simple  operation,  viz.,  from  a  determination  of  the  rela- 
tive quantities  of  soluble  and  insoluble  ash  in  tea  leaves.  With  the 
object  of  rendering  a  determination  of  this  sort  available,  I  have  made 
such  determinations  on  dried  leaves  of  various  kinds.  The  leaves, 
with  the  exception  of  the  tea  and  Paraguay  tea  leaves,  were  gathered 
