FERMENTATION  AND  CRYSTALLIZATION.  273 
tered,  and  that  is  in  spreading,  evenly  and  expeditiously,  the 
dry  sheet  on  the  oiled  one.  This  is  easily  overcome  by  working 
the  brush  freely  from  the  centre  to  the  circumference  of  the 
sheet. 
The  following  are  its  more  obvious  advantages: — 
1.  Its  extreme  cheapness  does  away  with  any  inducement 
which  might  otherwise  exist  to  employ  the  same  piece  more  than 
once.  A  ream,  or  480  sheets  of  paper,  costs  from  7s.  6d.  to 
10s.,  and  a  gallon  of  the  prepared  oil  about  3s.;  so  that  each 
sheet  costs  a  fraction  of  a  halfpenny.  This  does  not  include 
the  cost  of  manufacture,  which  would  slightly  increase  the  ex- 
pense. 
2.  Its  transparency. — When  applied  over  the  dressings  of  a 
stump,  or  any  cut  surface,  when  hemorrhage  may  be  feared,  the 
danger  can  be  seen  at  once,  and  obviated. 
3.  Its  lightness. — It  adds  little  to  the  weight  of  dressings, 
and  it  can  cause  little  or  no  pressure  on  a  tender  surface.  It  is 
particularly  useful  in  this  respect  for  covering  large  burnt  sur- 
faces. 
4.  It  extreme  adaptability. — It  can  be  applied  with  great 
niceness  to  any  part,  so  as  to  give  rise  to  little  or  no  inconveni- 
ence. When  applied  in  any  particular  way,  it  retains  the  form 
impressed  upon  it. 
5.  It  can  be  torn  easily  in  any  direction  In  this  respect  it 
contrasts  favorably  with  oiled  silk  and  gutta-percha. 
6.  It  can  be  made  of  any  required  strength  by  folding  it  one, 
two,  three,  or  more  times,  without  becoming  inconveniently 
thick. 
7.  It  possesses  a  certain  amount  of  adhesiveness,  which  is  in- 
creased by  the  heat  of  the  body,  and  thereby  more  effectually 
prevents  evaporation  from  wet  applications. — Pharmaceutical 
Journal  and  Transactions,  Feb.,  1859. 
RELATION  BETWEEN  FERMENTATION  AND 
CRYSTALLIZATION. 
In  1854,  Mr.  Schroeder,  in  connexion  with  Mr.  Dusch,  pub- 
lished a  paper  on  fermentation  and  putrefaction,  and  showed 
that  putrescent  and  fermentable  substances  could  be  indefinitely 
18 
