of  Animals  and  Vegetable . 41 
view  to  fee  what  power  vegetables  have.  I ill  all  relate 
thefe  experiments  in  the  order  in  which  they  were  made. 
They  were  began  in  the  fpring,  the  actions  of  life 
upon  which  growth  depends  being  then  upon  the  in- 
creale ; and  they  were  continued  till  thole  actions  were 
upon  the  decline,  and  alfo  when  all  actions  were  at  an 
end,  but  whilft  the  paflive  powers  of  life  were  ftill  re- 
tained. 
The  firft  were  made  on  a walnut  tree,  nine  feet  high 
in  the  ftem,  and  feven  feet  in  circumference  in  the 
middle. 
A hole  was  bored  into  it  on  the  North  fide,  five  feet 
above  the  furface  of  the  ground,  eleven  inches  deep 
towards  the  centre  of  the  tree,  but  obliquely  upwards, 
to  allow  any  fap,  which  might  ooze  through  the  wounded 
furface,  to  run  o it. 
I then  fitted  to  this  nart  a box  about  eiqht  inches 
wide  and  five  deep,  and  fattened  it  to  the  tree : the  bot- 
tom of  the  box  opened  like  a door  with  a hinge.  I 
Huffed  the  box  with  wool,  excepting  the  middle,  oppo- 
fite  to  the  hole  in  the  tree : for  this  part  I had  a plug  of 
f 
wool  to  fluff  in,  which,  when  the  door  was  fhut,  inclofed 
the  whole.  The  intention  of  this  was  to  keep  off  as 
much  as  poflible  all  immediate  external  influence  either 
of  heat  or  cold* 
Vol.  LXVIII.  G 
The 
