ACTION  OF  ALKALINE  CHLORIDES  ON  CALOMEL. 
391 
are  based,  the  writer's  opinion  and  conclusions  are  in  no  degree 
changed  as  to  the  true  cause  of  complaint  being  oxidation  of  the 
metal,  although  the  examination  has  unexpectedly  failed  to  es- 
tablish the  fact. 
Six  specimens  of  Pilulae  Hydrargyri  were  also  examined 
qualitatively  for  oxides  of  mercury,  and  quantitatively  for  mer- 
cury, with  the  following  results. 
SAMPLE. 
PERCENTAGE  OF 
Hg. 
Hg2  0. 
Hg  0. 
Deficient 
in  Hg. 
1st.  Olive  color,  good  consistence, 
2d.  Good  color  and  consistence. 
3d.  Olive  color,  too  stiff,  -    -  - 
4th.    "       u   good  consistence, 
5th.  Good  color  and  consistence, 
6th.  Standard  Laboratory  prep.  - 
30.3 
33.4 
29.1 
33. 
32.8 
33.4 
traces, 
notable  proportion 
notab  e  proportion 
notable  proportion 
traces, 
9.01 
13.7 
1. 
1.29 
These  specimens  are  from  the  same  sources  as  the  Hydrarg. 
cum  Creta ;  and  from  their  examination  it  appears  that  when 
well  made  this  preparation  loses  no  mercury,  neither  does  it 
oxidize  any  portion  of  it. 
Whether  the  new  form  in  which  it  is  now  coming  into  use, 
namely,  that  of  "Powdered  Blue  Mass,"  will  not  impair  its 
value,  by  subjecting  it  to  greater  risk  of  oxidation,  is  a  question 
worthy  of  inquiry.  The  reasons  for  its  use  in  such  a  form  are 
stated  to  be  its  greater  efficiency  and  certainty.  If  it  be  either 
more  efficient  or  certain  in  this  form,  the  circumstance  may 
probably  be  explained  by  the  fact  of  its  being  too  often  found 
materially  deficient  in  both  the  quantity  of  mercury,  and  method 
of  preparation. 
Naval  Laboratory,  New  York,  August,  1857. 
THE  ACTION  OF  THE  ALKALINE  CHLORIDES  ON  CALOMEL. 
By  Andrew  Fleming,  M.  D. 
The  question,  is  calomel  when  combined  with  the  chlorides  of 
the  alkalies  converted  wholly  or  in  part  into  corrosive  sublimate, 
changing  the  mild  purgative  into  a  very  powerful  preparation, 
