444 
EXAMINATION  OF  JAPANESE  PEPPER. 
different  way  (Liebig's  Annalen,  xcix.  p.  129.)  As  appears  from 
the  following  comparison,  my  table  agrees  so  closely  with  that 
calculated  by  Carius,  that  it  deserves  perfect  confidence  for  use  in 
the  preparation  of  the  acetometric  fluid. 
Amount  of  ammonia  in  the  fluid.  Specific  gravity. 
Carius. 
Otto. 
12  per  cent. 
0-9520 
0-9517 
11  « 
0-9556 
0-9555 
10  « 
0-9593 
0-9593 
9  « 
0-9631 
0-9631 
8  " 
0-9670 
0-9669 
7  " 
0-9709 
0-9707 
6  « 
0-9749 
0-9745 
5  « 
0-9790 
0-9783 
Ohem.  Craz.,  July  1,  1857,  from  Liehig's  Annalen,  April  1857. 
EXAMINATION  OF  JAPANESE  PEPPER,  THE  FRUIT  OF 
THE  XANTHOXYLUM  PIPERITUM  OF  DE  OANDOLLE. 
By  John  Stenhouse,  L.L.D.,  F.R.S. 
About  three  years  ago,  I  published  a  cursory  examination  of 
Japanese  pepper,  and  described  a  crystalline  principle,  to  which 
I  gave  the  name  of  Xanthoxylin,  made  with  a  specimen  received 
from  my  friend  Daniel  Hanbury,  jun.,  Esq.  Having  recently 
obtained  a  larger  quantity  of  the  same  material,  I  was  enabled 
to  submit  it  to  a  more  extended  examination. 
"  Japanese  pepper  is  the  product  of  Xanthoxylum  piperitum^ 
De  Cand.,  (Fagara  piperita,  Linn.),  a  tree  of  Japan  of  the 
natural  order  Rutacse,  figured  and  described  by  Koempfer,  in 
1712. 
u  It  consists  of  roundish  sessile  capsules  of  the  size  of  a 
peppercorn,  which  appear  to  have  been  nominally  four  in  number, 
situated  at  the  extremity  of  a  peduncle,  though  but  one  or  two 
are  usually  fully  developed.  The  capsules,  which  are  externally 
reddish  brown,  have  their  outer  covering  beset  with  numerous 
prominent  tubercles,  enclosing  an  acrid  liquid,  to  which  the 
pepper  owes  its  pungent  flavor.  The  seeds  are  black,  shining, 
and  devoid  of  pungency ;  from  dehiscence  of  the  capsules 
