AmAp%;moltm'}     Study  of  Urine,  Sputum  and  Blood.  171 
and  to  flood  the  specimen.  When  all  stain  is  removed  it  is  well  to 
add  a  weak  solution  of  methyl  blue  for  one-half  minute  and  remove 
the  stain  as  above.  The  specimen  is  now  dried  in  the  air,  when  a 
drop  of  balsam  is  added  to  its  centre  and  a  cover-glass  is  gently 
placed  on  this  balsam,  which  it  spreads  by  its  weight.  Where  the 
process  of  drying  is  after  the  manner  of  (2),  both  organic  and  inor- 
ganic substances  remain  unchanged,  and  it  was  with  a  view  to  the 
preservation  of  all  sediments  found  in  urine  that  I  recommended 
the  following  mounting  medium  i1  Liquor  acidi  arsenosi  (U.S. P.), 
1  fluid  ounce ;  salicylic  acid,  y2  grain ;  glycerin,  2  fluid 
drachms.  Warm  slightly  until  solution  is  affected,  when  add  acacia 
(whole  tears),  and  again  warm  until  solution  is  saturated ;  after 
subsidence,  decant  clear  supernatant  liquid.  A  drop  of  formalin 
(40  per  cent.)  may  be  added  to  this  mixture  if  desired.  By  means 
of  a  glass  rod  a  drop  of  this  medium  is  placed  on  the  centre  of  the 
specimen,  when  it  will  be  seen  that  the  remaining  urine  surrounds 
the  medium,  and  to  effect  an  equal  distribution  of  the  substances 
mounted,  a  fine  needle  is  carried  from  the  outer  margin  of  the  urine 
to  the  centre  of  the  medium  until  the  two  show  no  tendency  to 
separate.  A  cover-glass  is  moistened  by  the  breath  and  allowed  to 
fall  gently  upon  the  medium,  which  is  spread  by  its  own  weight. 
Slides  thus  prepared  should  be  kept  in  a  cool  place  on  a  perfectly 
level  surface  for  at  least  twenty-four  hours,  after  which  time  they 
can  be  rung  with  any  form  of  microscopic  cement.  No  stain  can 
be  used  where  specimens  are  mounted  in  this  medium.  A  pecu- 
liarity of  this  medium  is  that,  on  the  application  of  heat  or  agita- 
tion, it  becomes  filled  with  small  air  bubbles.  This  was  at  first 
thought  a  possible  objection,  but  I  find  specimens  mounted  Janu- 
ary, 1897,  containing  many  bubbles,  show  every  characteristic 
presented  by  the  same  urine  studied  after  the  usual  method  em- 
ployed. 
The  study  of  sputum  is  best  conducted  by  pouring  the  sputum  on 
a  clear  piece  of  glass  and  selecting  for  examination  the  small  masses, 
if  any  are  present.  This  mass  is  placed  between  two  cover-glasses 
or  slides  and  compressed  firmly,  after  which  the  glasses  are  sepa- 
rated by  a  sliding  movement  and  allowed  to  dry  in  the  air.  When 
perfectly  dry,  pass  three  times  through  the  flame  and  then  add  a 
1  New  York  Med.  Journal,  November  4,  1899. 
