RHIGOLENE,  ETC.  365 
produced,  were  it  not  for  the  ice  which  surrounds  the  bulb  of  the 
thermometer.  This  result  may  be  approximately  effected  by  the 
common  and  familiar  "  spray  producer,"  the  concentric  tubes  of 
Mr.  Richardson  not  being  absolutely  necessary  to  congeal  the 
tissues  with  the  rhigolene,  as  in  his  experiments  with  common 
ether.  I  have  for  convenience  used  a  glass  phial,  through  the 
cork  of  which  passes  a  metal  tube  for  the  fluid,  the  air- tube  be- 
ing outside,  and  bent  at  its  extremity  so  as  to  meet  the  fluid-tube 
at  right  angles,  at  some  distance  from  the  neck  of  the  bottle. 
Air  is  not  admitted  to  the  bottle,  as  in  Mr.  Richardson's  appa- 
ratus, the  vapor  of  the  rhigolene  generated  by  the  warmth  of  the 
hand  applied  externally  being  sufficient  to  prevent  a  vacuum  and 
to  ensure  its  free  delivery  ;  15°  below  zero  is  easily  produced  by 
this  apparatus.  The  bottle,  when  not  in  use,  should  be  kept  tightly 
corked,  a  precaution  by  no  means  superfluous,  as  the  liquid 
readily  loses  its  more  volatile  parts  by  evaporation,  leaving  a 
denser  and  consequently  less  efficient  residue.  In  this,  and  in 
several  more  expensive  forms  of  apparatus  in  metal,  both  with 
and  without  the  concentric  tubes,  I  have  found  the  sizes  of  72 
and  78  of  Stub's  steel  wire  gauge  to  work  well  for  the  air  and 
fluid  orifices  respectively  ;  and  it  may  be  added  that  metal  points 
reduced  to  sharp  edges  are  preferable  to  glass,  which,  by  its  non- 
conducting properties,  allows  the  orifices  to  become  obstructed 
by  frozen  aqueous  vapor. 
Freezing  by  rhigolene  is  far  more  sure  than  by  ether,  as  sug- 
gested by  Dr.  Richardson,  inasmuch  as  common  ether,  boiling 
only  at  about  96°  instead  of  70°,  often  fails  to  produce  an  ade- 
quate degree  of  cold.  The  rhigolene  is  more  convenient  and 
more  easily  controlled  than  the  freezing  mixtures  hitherto  em- 
ployed. Being  quick  in  its  action,  inexpensive  and  comparatively 
odorless,  it  will  supersede  general  or  local  anaesthesia  by  ether  or 
chloroform  for  small  operations  and  in  private  houses.  The 
opening  of  felons  and  other  abscesses,* the  removal  of  small 
tumors,  small  incisions,  excisions  and  evulsions,  and  perhaps  the 
extraction  of  teeth,  may  be  thus  effected  with  admirable  ease 
and  certainty ;  and  for  these  purposes  surgeons  will  use  it,  as 
also,  perhaps,  for  the  relief  of  neuralgia,  chronic  rheumatism, 
&c,  and  as  a  styptic,  and  for  the  destruction  by  freezing  of  erec- 
