*46  THE  TROPICAL  AGRICULTURIST.  [June  i,  iS93i 
valued  by  the  expert  as  shown  by  the  prioeB  paid. 
Only  by  experimenting  on  the  spot  and  especially 
in  the  Tea  Factory  can  the  Chemist  tell  us  this. 
Meantime  here  is  Mr.  Hughes’  paper : — 
So  much  has  has  been  said  and  written  of  late  in 
reference  to  the  respective  qualities  of  Indian,  Ceylon 
and  China  tea,  more  particularly  in  regard  to  the 
tannin  contained  in  each,  that  some  Comparative 
Analyses  will  probably  be  of  interest.  Accordingly 
samples  fairly  representative  of  these  teas  were  fur- 
nished the  writer  by  Messrs.  Elliot,  Lack  & Porter, 
a firm  of  brokers  dealing  in  the  three  kinds  of  tea 
abovenamed  and  therefore  quite  impartial  in  the 
matter.  The  analytical  results,  which  have  occupied 
some  time  and  trouble,  are  arranged  in  the  following 
tabulated  form.  The  names  and  description  of  the 
specimens  are  first  given,  followed  by  the  market 
price  at  which  they  were  sold,  to  which  has  been 
added  the  normal  value  of  each  tea  by  way  of 
comparison. 
This  was  desirable,  because  of  late  there  has  been 
a poor  demand  for  tea  of  high  quality  and  a large 
demand  for  tea  of  a comparatively  low  quality ; the 
consequence  being  that  at  public  sales  the  latter 
have  commanded  unusually  high  figures  and  the 
former  unusually  low  ones.  How  far  these  market 
prices  have  agreed  with  the  practical  results,  a care- 
ful examination  of  the  analytical  details  will  show. 
In  order  to  assist  in  this  examination  it  may  be  useful 
to  take  the  various  items  as  they  present  themselves 
in  the  table  and  offer  a few  remarks  by  way  of 
explanation. 
1.  The  Percentage  of  Water  expelled  at  a tem- 
perature of  212°  F.  varies  from  563  in  No.  3 to  8-86 
in  No.  5.  The  China  teas  are  evidently  not  so  highly 
dried  as  the  Indian  and  Ceylon  specimens. 
2.  The  Proportions  of  Oil  and  Chlorophyll  show 
considerable  variations  No.  3 which  fetched  11  id  con 
taining  the  least  1T0  per  cent,  while  No.  2 which 
fetched  only7|d.  contained  the  most  3"23.  These  results 
however  must  be  considered  as  r-.tl.er  < xceptional, 
for  No.  1 contaiuing  2‘47  sold  for  Is  3d  and  No.  5 con- 
taining 2’70  sold  ior  Is  7d.  A hign  peroen  aje  being 
generally  associated  with  a good  market  p-ice. 
3.  The  amount  of  Tannin  is  expected  under  two 
headings,  first  the  percentage  yielded  to  the  umhI 
5 minutes’ infusion  made  by  pouring  a definite  quantity 
of  boiling  water  upon  a definite  quantity  of  tea  ; 
secondly,  the  total  amount  of  tannin  yielded  after  boiling 
for  30  minutes. 
In  each  case  Assam  yielded  the  most,  Ceylon  next  and 
China  the  least,  but  the  differences  are  by  no  means 
large  and  certainly  do  not  justify  all  the  fuss  that 
has  been  made  about  the  respective  quantities  of 
tannin.  At  least  so  far  as  these  analyses  indicate, 
the  total  tannin  varies  from  9 40  in  No.  5 China  to 
14-76  in  No.  1 Assam,  the  former  being  sold  at  Is  7d 
and  the  latter  at  Is  3d,  both  being  relatively  high 
priced  and  the  normal  value  put  down  at  Is  51  in 
each  case.  In  No.  2 there  is  1180  while  No.  3 4 and  6 
praotioally  contain  very  similar  quantities  of  tannin. 
Comparing  these  results  with  the  figures  giving  the 
proportion  of  tannin  yielded  by  6 minutes’  inludon 
with  boiling  water,  we  observe  that  of  the  1 4*76 
present  in  No.  1 there  is  10  35  dissolved  out  or  70  per 
cent  of  the  whole;  while  id  No.  5 of  the  total  9 40 
there  is  dissolved  out  as  much  as  7 80  or  83  per 
cent  of  the  total  tannin  present  in  the  China  Tea. 
Tannin  therefore  being  soluble  inversely  according  to 
the  percentage  present.  Assam  tea  contains  more 
tannin,  but  yields  it  to  an  infusion  more  graduallv, 
in  other  words  if  we  use  Indian  Tea  and  wish  to 
avoid  an  excessive  quantity  of  tannin  we  should  allow  it 
to  infuse  for  a morter  time  than  China  Tea.  Con- 
sequently for  obtaining  a cup  of  tea  quicl-ly  Indian 
and  Ceylon  Tea  are  more  efficacious  than  China  Tea 
4.  — Theine  has  also  been  arranged  under  two 
headings;  namely  the  amount  yielded  by  the  nBual  5 
minutes’  infusion  with  boiling  water,  and  the  total 
amount  yielded  by  treatment  with  slaked  lime  and 
hot  water  with  subsequent  extraction  by  ohloroform 
and  evaporation.  It  will  be  noticed  that  the  vaca- 
tions of  the  total  Theine  are  inconsiderable,  the 
Assam  specimens  containing  ihe  most,  also  that  of  the 
total  386  in  No.  1,  3"33  was  yielded  in  the  5 minutes' 
infusion,  or  nearly  87  par  cent  of  the  total  quantity. 
On  the  other  hand  No.  3 which  contained  3 36  only 
yielded  2-13  or  63  per  cent  of  the  whole,  but  this  No  3 
specimen  is  evidently  Bomewhat  abnormal  as  will 
appear  more  clearly  present'y.  The  alkaloid  Theine 
containing  as  it  does  a high  proportion  of  soluble 
uitrogf  n no  doubt  exerts  an  important  medicinal  effect 
but  any  variation  in  the  quantity  present  cannot  be 
detected  by  the  tea  expert,  for  the  simple  reason  that 
it  possesses  no  distinctive  tis'e  or  smell  whereby  its 
presence  in  large  or  small  quantity  can  be  detected, 
and  consequently  it  can  in  no  way  affect  the  valuation 
for  market  purposes. 
5. — The  figures  for  woody  fibre  (cellulose)  are  very 
similar  iu  all  the  samples  with  the  exception  of  No.  3 
in  which  instead  of  the  usual  8*20  or  8-50  per  oent 
there  is  as  much  as  10-40  or  an  increase  of  upwards 
of  20  per  cent. 
6.  — The  figures  for  soluble  ash  are  very  interesting 
because  they  appear  more  than  anything  else  to  agree 
with  the  actual  market  prioe  : — 
Thus  No.  5 with 
No.  1 „ 
No  3 „ 
No.  2 „ 
No.  4 ,, 
No.  6 „ 
4'01  soluble  ash  sold  at  Is  7d 
373  „ „ Is  3d 
3-46  „ „ 0s  11  §d 
306  „ „ 0s  7id 
306  „ „ 0s  7Jd 
3 06  „ „ Os  6£d 
7. — The  figures  for  insoluble  aBh  show  al»o  a wonder- 
ful agreement  with  the  market  price,  inversely  with 
the  qoantity  found. 
Thus  No.  5 which  contains  1-92  said  for  le  7d 
No.  1 „ 
„ 2-27 
„ Is  3d 
No.  3 „ 
„ 2-47 
„ 0s  lljd 
No.  4 „ 
2-61 
0s  7id 
No.  6 ,, 
„ 2-70 
,,  0s  6§d 
No.  2 „ 
„ 2-94 
„ 0s  7Jd 
The  samples  2,  4 and  6 contained  the  same  quantity 
of  soluble  ash  and  very  similar  quantities  of  in- 
srluble  ash  while  the  market  price  only  varied 
from  6§d  to  7$d. 
8. — The  variation  in  nitrogen  is  very  alight  No.  3 
containing  the  least  3-80  and  No.  5 the  most  4‘08. 
Taken  with  the  ash  determinations,  a high  percent- 
age of  nitrogen  may  be  regarded  as  indicative  of  a 
superior  quality  of  tea. 
9.  — The  weight  of  the  dried  residue  left  on  evapora- 
tion of  a portion  of  the  water  extraot  obtained  by 
the  five  minutes  infusion  gives  a practical  illustra- 
tion of  the  diff,  renoe  between  Indian  and  Oeylon 
taken  together  and  China  tea.  The  former  yield  a 
larger  quantity  and  more  highly  coloured  liquor. 
The  dried  water  extraot  only  varies  iu  the  former 
irom  24  13  id  No.  3 to  25-06  in  No.  1,  a very  slight 
variation.  In  the  two  China  teas,  however,  there  is 
only  23-20  in  the  hist  quality  and  only  20'40  in  the 
inferior  quality.  Consequently  more  China  tea  would 
have  to  be  used  in  order  to  produce  the  same  quantity 
of  the  same  coloured  liquor.  The  question  of  flavour 
is  of  course  auother  matter;  at  present  it  is  only 
the  few  who  desire  flavour. 
The  public  care  more  for  quantity  and  colour 
than  for  quality,  and  hence  the  extended  demand 
for  Assam  and  Ceylon  tea  and  for  a |coarser,  but 
more  le-fy  quality  provided  it  yields  a good  deep 
coloured  liquor.  It  is  this  demand  that  has  so  af. 
feoted  the  market  of  late  and  these  analyses  so 
far  «s  they  go,  help  to  explain  why  such  a de- 
mand has  arisen. 
In  table  II.  a comparison  of  these  six  samples 
has  been  made  with  » view  of  ascertaining  the 
ixtsnt  to  whioh  variation  occuis  in  the  propor- 
tions of  leaf,  stalk  and  total  water  extraor.  A defi- 
nite quantity  of  tea  was  taken  in  each  case  ana 
thoronchly  exhausted  by  continued  boiliDg  with  fresh 
quantities  of  water.  Alter  pouring  off  the  final  < x- 
hauation,  the  stalks  were  ea  efully  separated  from 
the  leafy  portion,  hoth  were  (hen  dried  separately 
at  212°  F and  weighed.  The  results  will  be  interesting 
to  planters  as  well  as  tea  expertB  and  suggests  further 
investigation,  John  Hughes. 
Aca'ytical  Laboratory,  79  Mark  Lane,  London,  E.C. 
