. tf  Animals  and  Vegetables.  27 
exp.  xxxiv.  Several  leaches  having  been  put  into  a 
bottle,  and  that  bottle  immerfed  in  the  cold  mixture,  the 
ball  of  the  thermometer  being  placed  in  the  middle  of 
them,  the  quickfilver  funk  to  310;  and  by  continuing 
the  immerfion  for  a fufficient  time  to  deftroy  life,  the 
quickfilver  rofe  to  3 20,  and  then  the  leaches  froze.  In 
all  thefe  experiments  none  of  the  animals  returned  to 
life  when  they  became  thawed. 
Finding  that  thefe  imperfect  clafles  of  animals  are 
capable  of  varying  their  heat  to  that  ftandard  which  can 
freeze  the  folids  or  fluids  when  dead,  and  not  much  far- 
ther before  death  enfues,  I wiflied  to  determine  to  what 
degree  of  heat  the  animal  could  be  brought. 
exp.  xxxv.  A healthy  viper  was  put  into  an  atmo- 
fphere  of  10  8°,  and  allowed  to  flay  feven  minutes,  when 
the  heat  of  the  animal  in  the  ftomach  and  anus  was 
found  to  be  92°^,  beyond  which  it  would  not  rife  in  the 
above  heat.  The  fame  experiment  was  made  upon  frogs 
with  nearly  the  fame  fuccefs. 
exp.  xxxvi.  An  eel  very  weak,  its  heat  at  440,  which 
was  nearly  that  of  the  atmofphere,  was  put  into  water  at 
65°,  for  fifteen  minutes;  and,  upon  examination,  it  was 
of  the  fame  degree  of  heat  with  the  water. 
exp.  xxxvii.  A tench,  whofe  heat  was  410,  was 
put  into  water  at  65°,  and  left  there  ten  minutes;  the 
E 2 ball 
W ' ' 
