'•}  On  the  Detection  of  Exhausted  Ginger.  345 
N. 
0. 
P. 
R. 
S. 
T. 
U. 
V. 
IV. 
Origin  of  Ginger. 
Jamaica. 
Jamaica. 
Jamaica. 
Jamaica. 
Jamaica. 
Cochin. 
Cochin. 
Cochin. 
African. 
African. 
Average. 
11-26 
10  98 
13*95 
1276 
I3'96 
10-64 
i3"50 
1323 
I5'97 
13-70 
13-00 
3'90 
3' 29 
3'45 
3-8i 
3-62 
3-66 
3-90 
3'66 
Soluble  ash.  ...... 
170 
1 -41 
3 '05 
175 
171 
171 
203 
2  04 
2-28 
2-41 
2-0I 
Cold-water  Extract,    .  . 
15  65 
13-25 
14-40 
12-25 
11-85 
13-00 
8-65 
11-65 
io-8o 
I0"I0 
12*12 
Somewhat  closer  figures  are  obtainable  by  calculating  the  results 
on  the  moisture-free  samples,  but  even  then  the  figures  show  a  good 
deal  wider  variation  for  the  soluble  ash  than  was  observed  by  Dyer 
and  Gilbard,  while  the  cold-water  extract  also  shows  a  wider  range 
than  we  had  expected.  Sample  T  presents  the  peculiarity  of 
yielding  the  average  proportion  of  soluble  ash,  but  an  abnormally 
low  water-extract.  On  the  other  hand,  sample  0,  which  gave  the 
lowest  soluble  ash,  yielded  a  cold-water  extract  above  the  average. 
It  appears,  therefore,  that  neither  the  soluble  ash  nor  the  cold- 
water  extract  affords  by  itself  a  perfectly  safe  means  of  deciding  as 
to  the  presence  of  exhausted  ginger,  but  by  a  combination  of  the 
two  data  it  is  possible  to  arrive  at  a  more  definite  conclusion. 
More  extended  observation  is  needed  before  anything  like  a 
definite  limit  of  composition  can  be  assigned  to  genuine  ginger,  and 
hence  it  is  desirable  to  leave  a  wide  margin  when  stating  the  pro- 
portion of  exhausted  ginger  present  in  a  sample.  But,  meanwhile, 
there  is  no  difficulty  in  ascertaining  the  presence  of  the  adulterant 
when  it  has  been  added  in  such  quantities  as  to  bring  the  soluble 
ash  down  to  something  like  1  per  cent.,  and  the  cold-water  extract 
to  less  than  8  per  cent.;  and  this  is  the  case  with  not  a  few  gingers 
in  the  market.  The  adulteration  has  been  admitted  in  several  cases 
of  this  kind  which  have  come  under  our  notice. 
We  have  pleasure  in  acknowledging  the  valuable  assistance  ren- 
dered by  Mr.  H.  Court  and  Mr.  R.  Waterhouse  in  making  the 
experiments  above  recorded. 
Dr.  K.  J.  Baver  claims  to  have  discovered  a  new  element  in  French  beauxite. 
— (Chem.  Zeitung,  18,  671). 
