AmAprWr  £s6arm" }  Studies  on  the  Action  of  Salicylic  Acid  on  Ferments.  179 
most  suitable  to  engender  alcoholic  fermentation  (about  80°  F.),  and 
then  tested  for  glucose  sugars  by  means  of  Fehling's  solution  without 
any  result.  I  also  tried  the  action  of  the  salicylic  acid  solution  upon 
a  solution  of  starch  which  had  previously  been  " inoculated"  with  a 
small  quantity  of  saliva.  After  standing  several  days  I  could  not  find 
the  smallest  trace  of  glucose  sugar.  From  this,  salicylic  acid  acts  upon 
the  soluble  ferment  (ptyalin)  contained  in  saliva,  preventing  the  hydra- 
ting  action  upon  the  amy  loses. 
Then,  again,  I  have  found  that  the  above  solution  of  salicylic  acid 
acts  chemically  upon  the  cellulose  walls  of  dead  torulse,  destroying 
them  in  a  similar  manner  to  the  organized  ferments  already  described 
at  the  commencement  of  this  paper,  but  it  (the  acid)  has  no  action  on 
the  living  tomla.  This  shows  that  a  chemical  change  must  have  taken 
place  in  the  molecular  structure  of  the  cellulose  wall  of  the  cell  after 
death  of  the  organism. 
It  is  a  well-known  fact  that  in  every  brewery  the  yeast  becomes 
deteriorated  at  certain  times,  and  hence  the  beer  brewed  by  such  yeast 
is  not  so  good  as  formerly.  This  is  due  to  " disease  ferments"  in  the 
yeast  (the  organisms  I  have  alluded  to  in  the  early  part  of  this  paper). 
The  common  remedy  is  for  the  brewer  to  change  his  yeast.  But  I 
have  found  that  this  is  not  essential  if  the  brewer  waters  the  "  diseased 
yeast"  with  the  solution  of  salicylic  acid;  the  " disease  ferments"  are 
all  destroyed;  the  yeast  is  not  acted  upon  by  this  solution.  Yet  at 
the  same  time  the  yeast  so  treated  is  not  so  active  in  its  decomposition 
of  a  glucose  solution  into  alcohol.  This  yeast  can  be  revivified  by  an 
aqueous  solution  containing  0*25  gm.  of  potassium  nitrate  and  02  gm. 
of  sodium  phosphate  in  2000  c.c.  of  water.  In  fact,  the  torula  appears 
to  decompose  a  much  larger  quantity  of  sugar  (in  wort)  into  alcohol 
in  a  given  time  after  the  above  salts  have  been  added  to  2  liters  of 
wort  than  when  the  wort  is  not  so  treated.  It  appears  that  the  torula 
lives  its  life-history  to  a  certain  extent  by  extracting  the  potash  and 
phosphoric  acid  from  these  mineral  substances,  which  come  into  the 
wort  from  the  barley  and  hops.  Mitscherlich  long  ago  showed  that 
the  ash  of  yeast  gave  no  less  than  53  to  59  per  cent,  of  phosphoric 
acid,  and  from  28  to  39  per  cent,  of  potash.  Hence  it  may  be  that  a 
larger  amount  of  alcohol  would  be  produced  in  beers  by  the  addition 
of  small  quantities  of  the  above  substances  to  the  wort. 
From  the  above  investigation  the  following  conclusions  are  to  be 
drawn : 
