ME.  J.  LISTEE  ON  THE  EAELY  STAGES  OF  INFLAMMATION. 
051 
thii’ty  seconds,  the  corpuscles  will  be  all  cup-shaped,  and  Avill  exhibit  no  disposition  to 
aggregate.  But  no  effect  is  produced  on  the  formation  of  the  rouleaux  by  stirring  a 
drop  of  blood  in  the  same  way  for  a much  longer  time  in  an  atmosphere  free  from 
chloroform.  The  aggregation  of  the  corpuscles  is  not  prevented  merely  by  their 
becoming  cup-shaped,  and  therefore  unable  to  apply  themselves  to  each  other  as  usual. 
For  the  vapour*  of  caustic  ammonia,  while  it  renders  the  corpuscles  cup-shaped,  seems 
rather  to  increase  than  to  diminish  their  adhesiveness  and  aggregating  tendency,  and 
a temperature  of  about  32°  Fahe.  has  similar  effects  with  the  alkali'*.  Even  in  the 
mixture  of  blood  and  gum  many  of  the  corpuscles  are  cup-shaped,  though  adhering- 
together  with  peculiar  tenacity. 
"SMiether  or  not  it  -will  ever  be  possible  to  explain  these  curious  facts  upon  chemical 
principles  seems  very  doubtful ; but  in  the  meantime,  what  appears  most  striking  about 
them,  and  what  most  concerns  the  present  inquiry,  is  that  great  effects  may  be  pro- 
duced upon  the  adhesiveness  of  the  red  corpuscles,  both  in  the  way  of  increase  and 
diminution,  by  very  slight  changes  in  the  chemical  qualities  of  the  plasma. 
The  galvanic  current  produces  no  effect  upon  the  aggregation  of  the  red  corpuscles, 
either  of  man  or  of  the  frog,  as  I have  ascertained  by  placing  the  fine  platinum  wire 
extremities  of  the  poles  of  a powerfirl  battery  a short  distance  from  one  another  between 
two  slips  of  glass  beneath  the  microscope,  then  completing  the  circuit  by  shedding  a 
drop  of  blood  between  the  plates,  and  immediately  observing  the  result.  In  several 
such  experiments  I invariably  found  that  aggregation  took  place  as  usual,  and  the  only 
effect  produced  by  the  galvanism  was  a chemical  change  in  the  blood,  dependent  on 
electrolysis,  gradually  developing  itself  in  the  immediate  vicinity  of  the  poles,  and 
causing  solution  of  the  corpuscles. 
* Since  this  paper  was  read,  I was  told  by  a gentleman  well  known  in  the  scientific  world,  that  he  had 
observed,  many  years  ago,  that  if  blood  was  shed  upon  a plate  of  glass  previously  heated  to  the  temperature 
of  100°  Fahe.,  the  red  corpuscles  showed  no  disposition  to  aggregation  till  the  glass  cooled,  when  the  blood 
became  kfiled,  as  he  supposed,  by  the  unnaturally  low  temperature.  This  appeared  to  me  entirely  irrecon- 
cileable  with  the  fact,  that  in  the  frog  the  red  corpuscles  aggregate  immediately  after  the  blood  has  been 
shed,  although  there  is  no  material  difierence  between  the  temperature  of  the  air  and  that  of  the  body  of 
the  animal.  But,  if  true,  it  would  have  important  bearings,  to  which  I need  not  here  allude,  upon  the  essen- 
tial nature  of  inflammation.  I have  therefore  thought  it  well  to  make  some  experiments  upon  the  point. 
The  plate  of  glass  upon  which  the  blood  was  to  be  placed  was  warmed  by  immersion  in  water  of  a known 
temperature,  and  quickly  but  carefully  dried.  A drop  of  blood  from  my  own  finger  was  then  at  once  shed 
upon  it,  and  without  loss  of  time  covered  with  a piece  of  thin  glass,  which  had  been  kept  warm  by  being 
laid  upon  a metallic  plate  of  the  same  temperature  as  the  water.  By  proceeding  in  this  way,  I was  able  to 
make  observations  upon  the  blood  very  soon  after  it  had  been  shed ; and  when  the  glass  was  about  100°  Fahe., 
the  aggregating  tendency  was  found  just  the  same  as  in  ordinary  cases,  and  I detected  short  rouleaux  already 
formed  within  five  or  six  seconds  of  the  escape  of  the  blood  from  the  vessels  of  the  finger.  The  same  state 
of  things  continued  when  the  water  was  as  high  as  136° ; but  when  its  temperature  was  carried  up  to  155°, 
the  red  corpuscles  lost  their  disc-shape  and  some  of  them  appeared  to  become  broken  up,  and  no  rouleaux 
were  formed  either  while  the  blood  remained  warm  or  after  it  had  cooled.  From  these  results,  it  is  evident 
that  heat  does  not  interfere  at  all  vrith  the  aggregating  tendency  of  the  corpuscles,  unless  it  is  sufficiently 
great  to  act  upon  them  chemically. 
