240 
AMYLENE. 
rine  algae,  being  decomposed  during  the  production  of  mannite, 
the  superficial  tissue  of  the  plant  is  deteriorated ;  this  is  espe- 
cially the  case  with  Laminaria  saccharina,  one  of  the  algae  which 
furnishes  the  most  mannite ;  with  the  microscope  we  perceive, 
that  the  pulverulent  and  white  layer  of  mannite  is  accompanied 
by  a  great  many  isolated  spherical  cellules,  proceeding  from  the 
destruction  of  the  plant ;  water  put  to  them  dissolves  the  man- 
nite, and  leaves  these  cellules  at  liberty.  A  piece  on  which  there 
was  no  mannite,  showed  these  same  cellules  in  juxtaposition  and 
implanted  in  the  mucilage,  forming  a  continuous  smooth  layer, 
which  becomes  pulverulent  by  the  formation  of  mannite. 
The  body  which  causes  the  alteration  of  the  mucilage  in  the 
algae,  is  probably  the  albuminous  matter  which  all  these  vegeta- 
bles contain,  and  which  decomposes  in  the  air,  causing,  by  pro- 
longed decomposition,  those  disagreeable  odors  which  character- 
ize the  putrefaction  of  the  algae,  as  well  as  those  of  fresh  as  of 
sea  water. 
The  production  of  mannite  :  1st,  by  marine  algae  ;  2d,  by  the 
viscid  fermentation  of  wine  and  beer;  3d,  by  the  decomposition 
of  mucilaginous  vegetable  juices,  such  as  those  of  the  beet  root, 
dog's  grass,  ash,  &c,  leads  us  to  imagine  that  the  origin  of  this 
saccharine  matter  is  vegetable  mucilage,  rather  than  sugar,  as 
many  chemists  have  supposed.  I  think  we  may  venture  to  say 
that  wherever,  in  nature,  there  exists  at  once  vegetable  mucilage 
and  a  disoxidising  action,  mannite  will  be  produced. 
It  appears  probable,  that  the  viscid  substance  produced  during 
the  decomposition  of  many  beverages,  and  whose  real  nature  has 
only  lately  been  suspected,  is  nothing  but  vegetable  mucilage  of 
the  formula  C12  H10  O10. — The  Chemist,  March,  1857,  from 
Comptes  Eendus,  Dec,  1856. 
AMYLENE ;  A  NEW  ANAESTHETIC  AGENT. 
Dr.  Snow,  in  a  paper  read  before  the  Medical  Society  of 
London,  on  the  10th  of  January,  and  since  published  in  the 
Medical  Times  and  Crazette,  has  directed  attention  to  amylene 
as  an  anaesthetic  agent,  and  numerous  trials  of  this  substance  for 
producing  insensibility  are  now  being  made.  In  the  paper 
alluded  to  Dr.  Snow  briefly  traces  the  history  of  the  introduc- 
