UNGUENTUM  HYDRARGYRl  NITRATIS. 
211 
ON  UNGUENTUM  HYDRARGYRI  NITRATIS. 
By  Thomas  Jeffekson  Covell. 
(An  Inaugural  Essay  presented  to  the  College  of  Pharmacy  of  the  City  of 
New  York.) 
The  writer,  in  endeavoring  to  produce  a  proper  article  of 
ointment  of  nitrate  of  mercury,  has  reviewed  quite  all  that  has 
been  published  for  the  past  eighty-nine  years,  in  fifty-five  Phar- 
macopoeias and  Dispensatories  of  Continental  Europe,  Great 
Britain,  and  the  United  States  of  America,  upon  the  subject,  and 
does  herewith  present  a  synopsis  in  tabular  form. 
The  table  shows  at  a  glance  the  ingredients  and  quantities,  or 
parts  by  weight,  and  each  formula  is  numbered,  to  facilitate 
reference  as  to  where  that  formula  is  contained,  there  being 
nineteen  variations  of  the  fifty-six  works  referred  to. 
Thirty-one  of  the  Pharmacopoeias  use  lard,  twenty-three  lard 
and  olive  oil,  and  three  lard  and  neats-foot  oil,  as  a  vehicle.  The 
proportion  of  mercury  contained  in  the  various  ointments  varies 
from  8-3  per  cent,  to  5*25  per  cent.,  the  average  being  6*45 
per  cent. 
The  nitric  acid,  although  calculated  to  a  standard  of  sp.  gr. 
1*42,  has  undergone  the  greatest  and  most  notable  change ; 
starting  with  equal  parts  of  mercury  and  nitric  acid,  the  table 
ends  with  four  of  mercury  to  seventeen  of  nitric  acid  (1 ;  4*25). 
In  most  Pharmacopoeias  there  are  no  precise  directions  for  the 
manipulation,  in  which  lies  quite  all  the  requirements  for  suc- 
cess ;  and  for  that  reason  the  synopsis  will  be  followed  by  some 
detail  of  the  writer's  experience,  as  practical  as  possible. 
Synopsis  of  Unguentum  Ilydrargyri  Nitratis. 
n 
|2 
§3 
|4 
^5 
^7 
^8 
|9 
^10 
2 
3 
1 
1 
1 
1 
1 
1 
2 
1 
Acidum  nitricum, 
2-5 
4 
1 
2 
1 
2 
2 
2-5 
3 
2-5 
0 
0 
4 
0 
0 
12 
9 
0 
0 
0 
24 
32 
8 
12 
10 
4 
3 
8 
31 
15 
§11 
§12 
§13 
§14 
§15 
§16 
§17 
§18 
|19 
§20 
1 
2 
4 
2 
2 
2 
3 
4 
4 
o 
Acidum  nitricum, 
2 
3 
13 
3 
5 
6 
7 
12 
17 
8 
4 
16 
30 
16 
0 
8 
0 
30 
30 
0 
6 
16 
15 
8 
6 
12 
9 
15 
15 
9 
Oleum  bubulum.. 
0 
0 
0 
0 
18 
0 
24 
0 
0 
24 
