34°  Corrosive  Sublimate  in  Calomel.  {Am"ju0iy^i897arm' 
ductivity  of  calomel  in  water,  at  i8°  C,  have  found  that  I  litre 
of  water  dissolves  31  mg.  of  mercurous  chloride.  The  same  authori- 
ties,2 by  the  electrolytic  method,  have  found  that  1  litre  of  water, 
at  1 8°  C,  dissolves  1-52  mg.  of  silver  chloride.  The  difference  of  the 
relative  solubilities  of  silver  chloride  and  mercurous  chloride  is  1-58 
mg.  per  litre.  According  to  these  experiments,  there  would  be 
formed  a  certain  amount  of  silver  chloride,  when  a  saturated  aqueous 
solution  of  calomel  is  treated  with  silver  nitrate.  When  we  remem- 
bered that  one  part  of  silver  can  be  detected  in  800,000  parts  of 
water,  it  can  readily  be  seen  why  calomel  is  so  often  reported  as 
containing  corrosive  sublimate. 
Then  again,  if  mercurous  chloride  is  soluble  at  all  in  water,  and 
mercurous  sulphide  is  insoluble  in  the  same  menstruum,  it  naturally 
follows  that  hydrogen  sulphide  will  produce  a  reaction  with  a  satu- 
rated aqueous  solution  of  calomel. 
According  to  the  writer's  observations,  calomel  is  nearly  as  soluble 
in  alcohol  as  in  water,  but  is  insoluble  in  ether  ;  at  least,  an  alcoholic 
solution  of  calomel  frequently  gives  a  reaction  with  hydrogen  sul- 
phide, while  an  ethereal  solution  will  not  leave  a  residue  when 
evaporated  in  a  pure  atmosphere. 
While  it  is  impossible  to  countenance  any  laxness  in  a  matter  of 
this  kind,  still  the  writer  is  of  the  opinion  that  the  official  require- 
ments are  slightly  too  rigid.  As  the  matter  now  stands,  the  analyst 
must  practically  take  it  upon  himself,  if  he  reports  favorably  on  any 
material  submitted,  or  he  must  reject  every  sample  submitted 
to  him.  Calomel  does  occasionally  contain  corrosive  sublimate,  and 
it  is  necessary  to  keep  a  strict  surveillance  over  this  product.  But 
according  to  the  most  rigid  tests,  with  the  above  noted  exception, 
all  calomel  examined  by  the  writer  during  the  past  few  years  has  not 
contained  over  yorVor  °^  1  Per  cent-  °f  corrosive  sublimate. 
305  Cherry  Street,  Philadelphia. 
Volatile  oil  of  lovage,  according  to  E.  Braun  (Archiv  der  Pharm.,  235,  1), 
contains  (a)  a  terpene,  C10H16,  resembling  limonene,  but  not  giving  crystalline 
compounds  with  the  halogen  acids  ;  (b)  cineol,  C10H18O  ;  (c)  isovalerianic  acid  ; 
(d)  acetic  acid,  as  an  oxidation  product ;  (e)  benzoic  acid.  The  oil  commences 
to  boil  at  1700,  and  begins  to  decompose  at  2000  C. 
2 1893,  Ibid.,  12,  242. 
