SUBLIMING   TEMPERATURES  OF  POISONS.  249 
morphia,  they  have  been  grouped  as  above.  Of  solania  it  may- 
be stated  that  it  darkens,  and  grows  almost  black,  before  it 
melts. 
I  will  now  give  brief  notices  of  other  experiments  made  with 
the  apparatus  above  described,  and  then  bring  the  paper  to  a 
close  by  presenting  a  tabular  form,  embracing  the  principal 
poisons  which  we  encounter  as  white  powders  or  colorless  crys- 
tals. 
1.  Oxalate  of  ammonia  yields  sublimates  at  280°,  and  is 
wholly  dissipated  by  heat. 
2.  Binoxalate  of  potash  yi-elds  sublimates  at  280°,  and  leaves 
a  white  ash. 
Camphor  sublimes  at  150°. 
.Cyanide  of  Mercury  begins  to  sublime  at  320°. 
Oxide  of  antimony  sublimes  slowly  and  scantily  at  480°. 
Tartar   emetic  decrepitates   at  380°,  sublimes  slowly  and 
scantily  at  480°,  and  chars  at  about  550°. 
Sulphur  melts  and  sublimes  at  180°. 
The  volatile  metals  crushed  into  coarse  powder  sublime  as 
follows  : — 
Arsenic  .  .  .  at  230° 
Selenium  "  350° 
Cadmium  ...  44  480° 
Tellurium  "  500° 
Table  showing  the  approximate  results,  for  the  principal  poisons? 
of  sublimation  at  ascertained  temperatures  : — 
Temperature. 
Sublime. 
1.  Sublime   without    change  C  Corrosive  sublimate     .       .       .  200° 
of  form  or  color,  yielding  J  Cantharidina        ....  212° 
white  vapor.  ]  Calomel   240° 
V  Arsenious  acid     ....  280° 
Sublime.  Melt- 
2.  Sublimes,  then  melts,  with-] 
out  change  of  color,  and  L  Oxalic  acid  .  .  .  180°  280° 
is  wholly  dissipated.  J 
3.  Sublime,   melt  and    yield  J  Morphia        .       .       .      330°  340° 
carbonaceous  residue.      \  Strychnia      .       .       .     345°  430° 
