178     Studies  on  the  Action  of  Salicylic  Acid  on  Ferments.  {Amip°r"f  J«£rm- 
CHEMICAL  AND  MICROSCOPICAL  STUDIES  OX  THE 
ACTION  OF  SALICYLIC  ACID  ON  FERMENTS.1 
By  Dr.  A.  B.  Griffiths,  F.R.S.E.,  F.C.S.  (London  and  Paris). 
(Lecturer  on  Chemistry,  Technical  School,  Manchester;  Examiner  in  Chemistry,  Blairlodge 
School,  Polmont,  N.  B.,  etc.) 
My  attention  has  been  occupied  with  a  chemical  and  microscopical 
study  on  the  action  of  various  compounds  on  the  lower  forms  of  plant 
life.  I  have  already  presented  to  the  Chemical  Society  of  London  a 
paper  on  the  action  of  a  solution  of  ferrous  sulphate  on  certain  para- 
sitic diseases  which  attack  our  crops.  I  wish  here  to  detail  some 
studies  on  the  action  of  salicylic  acid  on  certain  ferments  (organized 
and  unorganized).  A  solution  of  salicylic  acid  was  prepared  contain- 
ing 0*2  gm.  of  the  acid  in  1000  c.c.  of  water.  A  drop  of  yeast  was 
placed  on  a  slide  under  the  microscope,  and  then  a  few  drops  of  the 
above  salicylic  acid  solution  was  run  in  between  the  slide  and  cover- 
slip,  when  I  found  it  had  no  action  on  the  true  alcoholic  ferment;  for 
1  was  unable  to  stain  the  protoplasm  of  the  cells  with  a  dilute  solution 
of  eosin,  showing  that  the  protoplasm  was  not  dead.  But  when  I 
operated  in  a  like  manner  on  certain  other  organized  ferments, — viz., 
on  Mycoderma  aceti,  Bacterium  lactis,  and  the  Butyric  bacillus — it 
was  very  different.  On  running  in  the  same  salicylic  acid  solution 
upon  slides  containing  these  various  ferments  they  were  quickly  de- 
stroyed. What  was  observed  under  the  highest  powers  of  the  micro- 
scope was  that  the  salicylic  acid  acts  chemically  upon  the  cellulose  or 
the  form  of  cellulose  making  the  external  Avails  of  these  lowly  or- 
ganisms. It  was  evident  that  the  acid  dissolved  the  cellulose  wall, 
and  in  some  cases  I  could  see  that  the  cellulose  wall  had  been  perfor- 
ated by  the  acid  solution. 
Beyond  these  facts,  I  have  found  that  the  above-named  aqueous 
solution  of  salicylic  acid  also  prevents  the  chemical  action  of  hydration 
by  means  of  the  soluble  zymases.  If  yeast  is  added  to  a  solution  of 
cane-sugar,  and  to  this  solution  the  salicylic  acid  solution  is  added,  no 
decomposition,  according  to  the  following  equation,  takes  place : 
C12H22On + H20 = C6H1206 + C6H12Og. 
That  is,  the  salicylic  acid  has  acted  upon  the  soluble  zymase  which  is 
secreted  by  the  Torula  cerevisise.  Hence  no  fermentation  takes  place. 
I  allowed  the  above  to  stand  for  two  or  three  days  at  a  temperature 
1  A  Paper  read  before  the  Koyal  Society  of  Edinburgh,  January  4,  1886. 
