538 
MANUFACTtJRE  OF  CHLORINE,  ETC, 
ment  of  Mr.  Speer  is  I  think  supported  by  facts.  Dr.  Pearson 
says,  "  It  is  probable  that  this  powder  was  made  for  several 
years  with  merely  the  heat  necessary  to  carry  oiF  the  sulphur 
and  calcine  the  bone,  in  an  open  vessel,  and  consequently  it  was 
of  a  light  clay  or  ash  color.  Its  property  of  turning  white  in  a 
greater  degree  of  fire  appears  to  have  been  a  subsequent  dis- 
covery." But  in  this  greater  degree  of  fire  the  powder  dis- 
charges copious  fumes  of  protoxide  of  antimony,  and  becomes 
less  active  as  a  medicine ;  and  at  length  assuming  the  hard, 
vitreous  state,  it  loses  all  medical  power.  On  one  occasion, 
when  I  had  obtained  the  powder  from  the  iron  ladle  paler  than 
usual,  I  took  several  doses  of  it  without  any  striking  efi"ect, 
which  proves  at  least  that,  in  this  state,  it  is  innoxious  ;  its 
taste  was  most  disagreeable,  whereas  the  white  powder  is  taste- 
less. I  imagine  that  in  this  form  the  powder  would  prove  to  be 
in  its  most  active  state ;  that  it  was  in  this  form  that  Lile's  and 
Schawanberg's  powder  obtained  its  celebrity ;  and  that  the  sub- 
sequent process  of  whitening  it  by  fire  deteriorates  its  medical 
effects  more  or  less  according  to  its  degree  and  continuance. 
But  it  is  of  little  use  to  insist  on  this  part  of  the  subject  in  the 
present  day.  If  the  whitening  process  in  the  skittle-pot  were 
relinquished,  and  the  light  ash-colored  powder  from  the  ladle 
were  accepted,  we  should  probably  have  an  efiicacious  medicine 
of  uniform  or  little-varying  strength. — Lond,  Pharm.  Journ.^ 
Sept.,  1869. 
ON  THE  MANUFACTURE  OF  CHLORINE  BY  MEANS  OF 
PERPETUALLY  -  REGENERATED  MANGANITE  OF  CAL- 
CIUM. 
Read  before  the  British  Association,  Exeter  meeting,  Section  B. 
By  Walter  Weldon,  F.C.S. 
Since  the  last  meeting  of  the  British  Association,  chlorine 
has  begun  to  be  manufactured  extensively  by  a  process  which 
depends  on  the  production  and  perpetual  regeneration  of  a  com- 
pound no  mention  of  which,  so  far  as  I  can  find,  as  yet  exists  in 
chemical  literature.  As  this  process,  besides  thus  producing 
and  continually  re-producing  what  I  believe  to  be  a  new  com- 
pound, reduces,  by  fully  80  per  cent.,  the  principal  item  in  the 
