of  Animals  and  Vegetables.  13 
external  ikin  of  the  parts.  I imagined  alfo,  that  what- 
ever effects  heat  or  cold  might  have,  when  applied,  would 
fooner  take  place  in  the  urethra  than  in  any  other  part 
of  the  body,  as  it  is  a projecting  part;  and  therefore,  if 
living  animal  matter  was  in  any  degree  fubjeCt  to  the 
common  laws  of  matter  in  this  refpeCt,  the  urethra 
would  be  readily  affeCted:  for  this  purpofe  I got  a per- 
fon,  who  allowed  me  to  make  fuch  experiments  as  I 
thought  neceflary. 
exp.  11. 1 introduced  the  ball  of  my  thermometer  into 
the  urethra  about  an  inch ; after  it  had  remained  there 
a minute,  the  quickiilver  rofe  only  to  9 1° ; at  two  inches, 
it  rofe  to  930;  at  four  inches,  the  quickiilver  rofe  to  940; 
and  when  the  ball  had  got  as  far  as  the  bulb  of  the  ure- 
thra, where  it  is  furrounded  by  warm  parts,  the  quick-- 
lilver  rofe  to  970. 
exp.  hi.  Thefe  parts  being  immerfed  in  water  heated  i 
only  to  65°  for  one  minute,  and  the  thermometer  intro- 
duced about  an  inch  and  a half  into  the  urethra,  the 
quickiilver  rofe  to  7 90:  this  was  repeated  feveral  times 
with  the  fame  fuccefs.  To  find  if  there  was  any  differ- 
ence in  the  quicknefs  of  the  tranfition  of  heat  and  cold 
in  living  and  dead  parts,  and  alfo  if  the  latitudes  to 
which  each  would  go  were  alfo  different,  I made  the 
following  experiments.  As  this  (viz.  the  urethra)  fiill 
4 appeared 
