128  Anomalous  Production  of  Ozone.  {^Ti,^' 
ON  THE  ACTION  OF  HEAT  UPON  SOLUTIONS  OF  BY  DRATED 
SALTS.* 
By  C.  R.  Tichborne,  F.  C.  S. 
The  author  used  for  the  examination  of  the  dissociation  of  water  of 
hydration,  such  salts  as  presented  a  change  of  color  when  passing 
from  the  hydrated  to  the  anhydrous  state.  He  had  experimented 
upon  those  of  cobalt,  copper  and  nickel.  Thus,  to  take  th3  familiar 
instance  of  cobalt,  the  anhydrous  salts  of  which  are  blue,  whilst  the 
hydrated  are  pink,  no  amount  of  boiling  will  convert  a  pink  solution 
of  cobalt  into  a  blue  one,  except  it  is  extremely  concentrated,  but  in 
every  case  such  salts  were  all  changed  into  the  anhydrous  condition 
on  boiling  under  pressure.  When  the  "  thermanalytic"  point,  as  the 
author  called  it,  was  reached,  the  pink  cobalt  salts  wrere  converted 
into  the  blue  ones,  copper  into  yellowish-brown,  and,  in  the  case  of 
chloride,  nearly  a  black  solution.  Some  caution  is  required  in  the 
performance  of  these  experiments  owing  to  the  danger  of  an  explosion. 
An  important  observation  made  in  connection  with  these  experiments 
was  the  fact  that  dilution  acted  differently  in  the  cases  of  chromatic 
change  produced  by  dehydration  and  those  producing  basic  results. 
It  is  exactly  the  reverse.  The  author  had  pointed  out  in  a  previous 
report  that  chromatic  changes  resulting  from  the  formation  of  basic 
salts  by  dissociation  (7.  e.  chromic  or  ferric  salts)  is  influenced  by  di- 
lution lowering  the  thermanalytic  point,  or  the  increase  in  volume  of 
water  will  assist  the  dissociation.  But  in  the  second  class  the  increase 
in  the  volume  of  water  ruins  the  thermanalytic  point  and  retards  the 
dissociation. 
Prof.  Sullivan  complimented  the  author  upon  the  importance  of 
this  investigation,  and  this  line  of  research  generally. — Ohem.  News, 
Jan.  19,  1872. 
ANOMALOUS  PRODUCTION  OF  OZONE. 
By  Henry  H.  Croft. 
Professor  of  Chemistry,  University  College,  Toronto. 
About  six  years  ago,  when  evaporating  some  syrupy  Iodic  Acid, 
prepared  according  to  Millon's  process,  over  sulphuric  acid,  I  noticed 
that  when  the  acid  began  to  crystallise,  the  air  in  the  jar  (covering 
*  Abstract  of  a  paper  read  before  the  Royal  Irish  Academy,  Jan.  8,  1872. 
