JAPANESE  ISINGLASS. 
355 
Ij  inches  broad,  full  of  cavities,  very  light  (each  weighing  about 
three  drachms),  rather  flexible  but  easily  broken,  and  devoid  of 
taste  and  smell.  Treated  with  cold  water,  a  stick  increases 
greatly  in  volume,  becoming  a  quadrangular,  spongy  bar  with 
somewhat  concave  sides  1|  inches  wide.  Though  not  soluble  in 
cold  water  to  any  important  extent,  the  substance  dissolves  for 
the  most  part  when  boiled  for  some  time,  and  the  solution,  even 
though  dilute,  gelatinizes  upon  cooling. 
2.  The  second  specimen,  also  from  Japan  (which  I  owe  to  the 
kindness  of  the  late  John  Reeves,  Esq.,)  resembles  the  preced- 
ing in  all  its  properties,  but  its  form  is  very  different,  it  being 
in  long,  shrivelled  strips  about  J  of  an  inch  in  diameter.  These 
strips  when  immersed  in  water  speedily  increase  in  volume,  and 
are  then  seen  to  be  irregularly  rectangular.  This  substance  in 
color  is  usually  whiter  than  the  preceding  ;  it  is  also  more  readi- 
ly soluble,  cleaner,  and  altogether  a  more  carefully  manufac- 
tured article. 
The  substance  under  notice  in  all  its  forms  is  used  by  the 
Europeans  in  China  as  a  substitute  for  true  isinglass,  for 
which  many  of  its  properties  render  it  highly  efficient.  That 
which  is  perhaps  most  distinctive,  is  its  power  of  combining 
with  a  very  large  proportion  of  water  to  form  a  jelly.  This 
property  is  due  to  the  principle  named  by  M.  Payen  Gelose,  of 
which  the  Japanese  sea- weed  product  mainly  consists.  The 
jelly  formed  by  boiling  this  sea-weed  product  or  crude  gelose  in 
water,  and  allowing  the  solution  to  cool,  requires  a  high  temp- 
erature for  fusion,  differing  in  this  respect  from  a  jelly  made  of 
isinglass  which  readily  fuses  and  dissolves  in  warm  water.  This 
character  occasions  a  peculiarity  in  the  taste  of  culinary  jellies 
made  of  the  new  material,  inasmuch  as  they  do  not  dissolve  in 
the  mouth  as  ordinary  animal  jelly.  The  jelly  of  gelose  is  but 
little  prone  to  undergo  change — so  little  indeed  that  sometimes 
under  the  name  of  sea-weed  jelly,  it  is  imported  to  this  country 
from  Singapore,  sweetened,  flavored  and  ready  for  use,  and  in 
this  state  it  may  be  kept  for  years  without  deterioration. 
Gelose'differs  from  animal  gelatine,  in  not  precipitating  tannic 
acid  ;  from  starch  jelly,  in  not  being  rendered  blue  by  iodine  ; 
from  gum,  by  its  insolubility  in  cold  water  and  its  great  gela- 
tinizing power.    From  the  mucilage  of  Ohondrus  crispus,  named 
