168 
ON  CHARCOAL  AS  A  DISINFECTANT. 
and  destroys  many  of  the  easily  alterable  ones,  by  resolving 
them  into  the  simplest  combinations  they  are  capable  of  forming, 
which  are  chiefly  water  and  carbonic  acid. 
It  is  on  this  oxidizing  property  of  charcoal  as  well  as  on  its 
absorbent  power  that  its  efficacy  as  a  deodorizing  and  disinfect- 
ing agent  chiefly  depends. 
Effluvia  and  miasmata  are  usually  regarded  as  highly  organized, 
nitrogenous,  easily  alterable  bodies.  When  these  are  absorbed 
by  charcoal,  they  come  in  contact  with  highly  condensed  oxygen 
gas,  which  exists  within  the  pores  of  all  charcoal  which  has  been 
exposed  to  the  air,  even  for  a  few  minutes ;  in  this  way  they  are 
oxidized  and  destroyed.  My  attention  has  been  specially  directed 
for  nearly  a  twelvemonth  to  the  deodorizing  and  disinfecting 
properties  of  charcoal,  and  I  have  made  an  immense  number  of 
experiments  on  this  subject. 
On  the  22d  of  February  last  I  brought  the  subject  before  the 
Society  of  Arts,  and  on  that  occasion  exhibited  a  specimen  of  a 
charcoal  respirator,  and  the  mode  of  employing  it.  I  likewise 
dwelt  at  some  length  on  the  utility  of  charcoal  powder  as  a 
means  of  preventing  the  escape  of  noxious  effluvia  from  church- 
yards, and  from  dead  bodies  on  board  ship  and  in  other  situations. 
On  the  9th  of  June  last  I  also,  in  a  letter  to  the  Society  of 
Arts,  proposed  to  employ  charcoal  ventilators,  consisting  of  a 
thin  layer  of  charcoal  enclosed  between  two  sheets  of  wire  gauze, 
to  purify  the  foal  air  which  is  apt  to  accumulate  in  water  closets, 
in  the  close  wards  of  hospitals,  and  in  the  impure  atmospheres 
of  many  of  the  back  courts  and  mews-lanes  of  large  cities,  all 
the  impurities  being  absorbed  and  retained  by  the  charcoal,  while 
a  current  of  pure  air  alone  is  admitted  into  the  neighboring 
apartments. 
In  this  way  pure  air  is  obtained  from  exceedingly  impure 
sources.  Such  an  arrangement  as  this,  carried  out  on  a  pretty 
large  scale,  would  be  especially  useful  to  persons  necessitated  to 
live  in  pestiferous  districts  within  the  tropics,  where  the  miasmata 
of  ague,  yellow  fever,  and  other  diseases  are  prevalent. 
The  proper  amount  of  air  required  by  houses  in  such  situations 
might  be  admitted  through  sheets  of  wire  gauze  or  coarse  canvas, 
containing  a  thin  layer  of  coarse  charcoal  powder. 
Under  such  circumstances  also  pillows  stuffed  with  powdered 
