Am.  Jour.  Pharm  ") 
Dee.  1,  1873.  J 
On  Tea. 
553- 
by  my  assistant  on  the  24th  of  August  this  year.  The  following  are 
the  results  : — 
Percentages  on  the  dried  leaves. 
The  Ash. 
Total. 
Soluble  in 
Insoluble 
Water. 
in  Water. 
1.  Oommon  tea,  . 
0  vL 
O  00 
9-37 
L  O  1 
2.  Paraguay  tea, 
6-28 
4-22 
2-06 
3.  Beech, 
.  4-52 
2-00 
2-52 
4.  Bramble,  . 
4-53 
1-84 
2-69 
5.  Raspberry 
.  7-84 
1-72 
6-12 
6.  Hawthorn, 
8-05 
3-78 
4-27 
7.  Willow, 
.  9-34 
4-16 
5-18 
8.  Plum, 
9-90 
5-66 
4-24 
9.  Elder, 
.  10-67 
3-19 
7-48 
10.  Gooseberry, 
13-50 
7-83 
5-67 
From  this  table  it  will  be  apparent  that  the  ash  of  Paraguay  tea 
is  the  only  ash  capable  of  being  mistaken  for  the  ash  of  tea  ;  the  total 
percentage  would  of  itself  exclude  all  the  others.  The  ash  of  Para- 
guay tea,  is,  however,  distinguished  from  the  ash  of  common  tea  by 
containing  a  higher  proportion  of  soluble  matter. 
The  ash  of  beech  and  of  bramble  is  distinguished  from  that  of  tea 
by  being  too  small  in  amount,  and  by  containing  too  little  soluble 
matter.    All  the  rest  are  exceedingly  unlike  tea  ash. 
The  determination  of  the  total,  the  soluble,  and  the  insoluble  ash 
in  leaves  are  made  with  great  facility.  Dried  leaves  burn  up  with 
great  ease  ;  and,  for  the  purpose  of  getting  a  complete  combustion 
there  is  no  occasion  for  the  employment  of  nitric  acid.  I  am  in  the 
habit  of  employing  about  2  grms.  of  the  dried  leaves  for  the  experi- 
ment. These  I  burn  in  a  small  platinum  dish,  and  when  the  result- 
ing  ash  has  become  grey,  I  allow  the  dish  to  cool  and  weigh  it  to- 
gether with  its  contents.  The  ash  is  then  heated  to  boiling  with  a 
little  water,  and  the  solution  filtered,  and  the  filtrate  evaporated  to 
dryness  in  a  small  platinum  dish  ;  the  resulting  residue  is  then  ignited, 
cooled  and  weighed.  Thus  I  get  determinations  of  "  total  ash"  and 
"  soluble  ash  ;"  the  "  insoluble  ash"  is  found  by  difference. 
Sand  is  sometimes  found  in  tea  leaves  ;  this  is  very  easy  of  detec- 
tion. It  will,  of  course,  remain  in  the  insoluble  portion  of  the  ash,, 
and  refuse  to  dissolve  when  that  is  treated  with  hydrochloric  acid„. 
