REMARKS  ON  THE  COHESION  FIGURES  OF  LIQUIDS.  343 
of  leadPb02  which,  on  account  of  this  property  is  very  largely 
employed  in  the  manufacture  of  chemical  matches. 
A  very  dry  mixture  of  about  two  parts  of  oxioTe  of  silver 
and  one  of  sulphur  ignites  by  friction  in  a  mortar,  or  even  be- 
tween folds  of  paper.  It  makes  no  difference  if  the  antimony 
compound  if  replaced  by  black  sulphide  of  antimony,  realgar, 
or  orpiment. 
The  same  thus  occurs  with  amorphous  phosphorus  as  with 
tannin.    Gallic  acid  does  not  induce  combustion. 
A  drop  of  phenic  acid  or  creosote  poured  on  very  dry  oxide 
of  silver  causes  an  instantaneous  flame.  > 
Flour  of  sulphur  also  ignites  when  triturated  with  this  oxide  ; 
selenium  the  same. — Chem.  News,  London,  May  7,  1864,  from 
Journ.  fur  Prakt.  Chemie,  xc,  32. 
FURTHEE  REMARKS   ON  THE    COHESION    FIGURES  OF 
LIQUIDS. 
By  Charles  Tomlinson. 
Lecturer  on  Science,  King's  Cullege  School,  London. 
A  wish  having  been  expressed  that  some  of  the  diagrams  of 
cohesion  figures,  exhibited  during  the  reading  of  my  paper  on 
the  3d  of  February  last,  should  be  reduced  and  engraved  on  wood 
for  insertion  in  the  Journal,  I  think  it  due  to  the  Society  to 
make  a  few  additional  remarks  in  connection  with  these  figures, 
which,  as  now  presented,  bear  about  the  same  relation  to  the 
originals  as  an  engraving  of  a  rainbow  does  to  the  real  object. 
But  although  the  exquisite  beauty  and  harmony  of  color  of  some 
of  these  figures  is  thereby  lost,  yet  a  certain  rough  idea  is  thus 
given  of  their  form  and  outline,  so  that  any  one  working  on  this 
subject  for  the  first  time  may  get  a  notion  of  the  kind  of  form 
he  has  to  expect. 
After  the  reading  of  my  paper,  a  number  of  questions  were 
put  as  to  the  variation  of  the  figure  by  changing  the  surface, 
etc.,  and  I  stated  that  water  seems,  in  all  respects,  to  be  best 
adapted  for  the  exhibition  of  these  figures.  In  a  paper  published 
in  the  "  Philosophical  Magazine  "  for  March,  1862,  some  par- 
ticulars are  stated  respecting  variations  in  the  figures  arising 
from  changes  in  the  adhesion  surface.     Thus,  a  drop  of  water 
