558  DECAY  OF  GUTTA  PERCHA. 
plant  was  supposed  to  be  the  spawn,  was  found  growing  luxuri- 
antly under  the  oak,  but  not  under  any  other  tree.  The  plant 
possesses  a  powerful  odor,  at  once  detected  on  breaking  the  soil. 
The  presence  of  the  plant  and  the  decay  of  the  wires  were  found 
coincident ;  the  absence  of  the  plant  and  a  most  perfect  state  of 
the  wires  coincident  also.  It  was  found  that  the  wires  in  one 
locality  passing  under  two  oak  trees  were  not  injured ;  in  this 
case  no  fruit  of  the  fungus  could  be  found  in  the  soil,  although 
plentiful  under  other  oak  trees  in  the  neighborhood.  With 
reference  to  the  decay  of  gutta  percha  in  iron  tubes  it  was  found 
at  Winslow  that  the  wires  through  the  entire  lengths  of  the  iron 
pipings  were  in  a  state  of  decay,  whilst  the  wires  in  the  wooden 
boxing  were  found  perfect.  The  decay  in  this  case  appears  to 
be  produced  by  a  cause  entirely  different  from  that  under  the 
oak  trees.  The  following  is  the  result  of  Mr.  Highton's  investi- 
gation : — 
With  reference  to  my  experiments  on  the  action  of  the  mycel- 
lium  of  a  fungus  on  gutta  percha,  I  have  for  some  months  been 
growing  one  of  the  class  called  agarious  campestris  in  contact 
with  gutta  percha. 
1.  find  as  the  result  that  the  mycelliem  of  this  fungus  does 
rapidly  destroy  the  insulating  properties  of  gutta  percha ;  and 
in  fact  it  appears  to  decompose  entirely  this  vegetable  gum.  I 
send  a  sample  showing  the  decay. 
I  am  trying  further  experiments,  an  account  of  which  I  hope 
ere  long  to  lay  before  the  Board. 
A  few  days  ago  I  examined  a  spot  near  Canterbury,  where 
the  gutta  percha  of  the  wires  had  entirely  decayed. 
The  soil  was  pure,  clean,  sharp,  red  sand,  and  there  appeared 
nothing  in  such  soil  to  induce  decomposition. 
But  at  that  spot  I  found  a  young  oak  tree,  which  could  only 
derive  its  nourishment  from  the  ground  through  which  the  wires 
passed.  And  upon  theses  roots,  both  living  and  dead,  I  found 
what  I  believe  to  be  the  mycellium  of  a  fungus,  the  same  as 
that  which  I  discovered  under  the  oak  trees  at  Berkhampstead. 
I  send  with  this  some  of  those  roots  upon  which  the  fungus 
can  be  distinctly  traced.  The  odor  arising  from  that  fungus 
appears  to  be  identically  the  same  as  that  from  the  fungi  at 
Berkhampstead. 
