REMARKS  ON  LEECHES. 
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observing  to  remove  dead  and  sickly  ones,  in  order  to  preserve 
the  rest,  as  the  diseases  affecting  leeches  are  mostly  epidemic  in 
their  character. 
It  is  necessary,  in  applying  leeches,  that  the  part  to  be  leeched 
should  be  perfectly  clean  and  free  from  smell  of  medicine  or  per- 
spiration. Handle  the  leeches  always  carefully,  and  with  clean 
hands.  Having  determined  upon  the  number  to  be  used,  place 
them  in  a  cupping-glass,  wineglass,  or  even  in  the  bottom  part 
of  a  chip  pill-box,  and  invert  it  over  the  part  affected.  Ic  is  often 
desirable  to  partly  fill  the  cupping-glass  with  water,  as  they  will 
bite  more  readily  when  covered  by  it.  When  they  have  attached 
themselves,  the  cup  can  be  gently  removed,  and  the  part  sur- 
rounded by  a  soft  cloth,  which  will  absorb  the  moisture  and  blood, 
and  catch  the  leeches  when  they  drop  off. 
It  often  occurs  that  leeches,  from  some  unknown  cause,  can 
not  be  made  to  bite  by  ordinary  means.  We  have  found  that, 
with  such,  the  best  success  attends  a  slight  scarification  of  the 
affected  part,  and  the  subsequent  application  of  the  leech,  by 
holding  it  in  a  soft  dry  towel,  and  directing  its  head  to  the  scari- 
fied part,  withdrawing  it  a  little  as  it  reaches  it,  thus  compelling 
it  to  fix  thereat.  Vinegar,  milk,  molasses,  etc.,  are  useless  and 
unnecessary  to  incite  leeches  to  bite. 
For  the  application  of  leeches  to  the  gums,  and  to  the  neck  of  the 
uterus,  tubes  are  made,  by  means  of  which  the  leech  is  compelled 
to  attach  itself  to  any  spot  desired. 
Pereira  states  that  "  several  circumstances  affect  the  fixing  of 
leeches;  as  the  condition  of  the  animal,  whether  healthy  or  other- 
wise ;  the  nature  or  condition  of  the  part  to  which  it  is  applied ; 
thus  leeches  will  not  readily  attach  themselves  to  the  soles  of  the 
feet  or  the  palm  of  the  hands,  or  to  the  hairy  parts — the  presence 
of  grease,  vinegar,  salt,  and  some  other  substances  will  prevent 
them  from  biting.  Durheims  says,  leeches  will  not  bite  those 
under  the  influence  of  sulphur,  on  account  of  the  evolution  of 
sulphuretted  hydrogen  by  the  skin.  The  effluvia  or  vapors  of  the 
room,  as  the  fumes  of  tobacco,  sulphur,  vinegar,  will  prevent 
their  biting,  or  even  cause  them  suddenly  to  fall  off." 
If  a  flow  of  blood  greater  than  that  swallowed  by  the  leech  is 
desired,  it  must  be  excited,  after  the  leech  drops  off,  by  warm 
fomentations  or  poultices. 
