582  The  Volatile  Products  of  PutrefaGtion.  {^%^oT.'i882.''"^ 
perties  of  the  glyceroborates  of  sodium  and  calcium  he  comes  to  the- 
following  conclusions  : 
First — The  disinfecting  power  of  any  antiseptic  is  in  inverse  ratio  to 
the  age  of  the  putrefying  material.  A  solution  of  chopped  meat  six 
days  old  will  require  a  much  smaller  proportion  of  disinfectant  than 
when  it  has  been  kept,  say  for  a  couple  of  months,  when  the  amount 
required  will  be  ten  times  greater. 
Secondly — If  we  wish  to  measure  the  power  of  antiseptics  by  tak- 
ing as  a  basis  their  disinfecting  properties,  when  applied  to  a  solution 
of  chopped  meat  of  normal  strength  (1  :  10),  we  shall  find  that  the 
most  powerful  compounds  are  potassic  permanganate,  calcic  hypochlo- 
rite, ferrous  sulphate  acidulated  with  acetic  acid,  carbolic  acid  and 
potassic  and  sodic  glyccroborate.  For  instance,  in  order  to  disinfect 
10  cubic  centimeters  of  the  normal  chopped  meat  solution  mentioned 
above  we  must  take  500  cubic  centimeters  of  a  saturated  solution  of 
salicylic  acid,  80  of  a  saturated  solution  of  carbolic  acid,  80  of  a  ten 
per  cent,  solution  of  sodic  glyccroborate  and  several  drops  only  of  a 
one  per  cent,  solution  of  potassic  permanganate. 
Thirdly — There  is  no  parallelism  in  the  disinfecting  action  of  an 
antiseptic  and  its  action  on  microbes;  potassic  permanganate,  for 
instance,  although  a  most  powerful  disinfectant,  exercises  no  power 
whatever  on  these  organisms.  On  the  other  hand,  alcohol,  which, 
after  a  long  time,  checks  their  development,  only  acts  as  a  very  weak 
disinfectant. 
Fourthly — There  is  no  parallelism  between  the  power  of  an  antisep- 
tic in  preventing  putrefaction  and  its  power  of  checking  it  when  once 
set  up.  Alcohol  and  carbolic  acid,  which  are  powerful  preventatives 
of  putrefaction^  act  but  feebly  when  ^^i^itrefaction  has  once  com- 
menced. Carbolic  acid,  therefore,  when  used  in  surgery,  acts  rather 
as  a  preservative  than  as  an  antiseptic. 
Fifthly — With  the  exception  of  a  very  small  number  of  bodies, 
such  as  corrosive  sublimate  and  other  powerful  poisons,  the  greater 
part  of  the  antiseptics  now  in  use,  more  especially  carbolic  acid,  have 
but  a  very  feeble  action  on  bacteria.  If  we  mix  20  cubic  centimeters 
of  the  above-mentioned  normal  solution  of  chopped  meat  with  50  or 
even  100  cubic  centimeters  of  a  saturated  solution  of  carbolic  acid,, 
the  larger  bacteria  are  rendered  motionless,  while  the  smaller  ones 
retain  their  vitality  and  powers  of  reproduction.  The  author  pos- 
sesses carbolized  solutions  four  months  old  still  rich  in  bacteria.  In 
