DISINFECTANTS  IN  ARRESTING  CATTLE  PLAGUE.  361 
be  carried  as  far  as  possible  short  of  endangering  the  health  of 
the  sound  animals  by  the  agents  employed.  Disinfectants  and 
antiseptics  have  necessarily  a  powerful  action  on  vital  phe- 
nomena ;  and  in  some  cases  it  may  happen  that  an  animal's 
vital  powers  are  so  diminished  by  the  disease  that  it  will  not 
have  strength  left  to  bear  the  remedial  treatment ;  but  even  in 
this  case  less  harm  will  be  done  by  its  use  than  if  the  animal  had 
been  allowed  to  die  of  cattle  plague. 
12.  Disinfection,  in  the  widest  sense  of  the  term,  includes 
deodorization,  and  means  the  neutralization  or  destruction  of  all 
substances,  arising  from  putrefying  organic  matter,  or  emanating 
from  diseased  animals,  either  injurious  to  health  or  offensive  to 
the  sense  of  smell. 
The  putrefactive  products  of  animal  and  vegetable  matter  are 
found  to  consist  of  some  or  all  of  the  following  gases  and 
vapors : — 
Sulphuretted  hydrogen, 
Phosphuretted  hydrogen, 
Ammonia, 
Phosphorus  and  nitrogen-bases  of  complex  constitution, 
Acetic,  butyric,  valerianic,  &c,  acids, 
Oarburetted  hydrogen, 
Hydrogen. 
Carbonic  oxide, 
Carbonic  acid, 
Nitrogen, 
Various  organized  animal  and  vegetable  products  of  little  or  no 
activity,  and 
The  special  virus  of  infection.  (The  latter  in  an  infected 
district.) 
13.  In  a  more  restricted  sense,  the  term  "  disinfectants  "  is 
used  to  express  those  agents  which  destroy  organic  or  offensive 
matter  by  oxidation  or  analogous  action ;  whilst  under  the 
term  "  antiseptics "  are  classed  those  agents  which  prevent 
chemical  change  by  destroying  the  tendency  to  putrefy,  The 
latter  are  termed,  by  Dr.  Angus  Smith,  colytics,  from  ko&m}  I 
arrest. 
14.  Oxidizing  disinfectants  are  by  far  the  best  known  and 
most  popular,  inasmuch  as  they  appeal  directly  to  popular  preju- 
