THE USE OF VEGETABLE TAR IN VETERINARY PRACTICE. 669 
granular and when rubbed on a surface the heat melts the 
basis and the irritant granules of the tar injure instead of 
having a beneficial influence. 
What then is the best method to use tar locally ? In my 
judgment it is in the comparatively new combination known 
as tarro-petrolene (or other equally well blended tar oint¬ 
ments) which at first appeared on the market with a trade 
mark attachment and in a black, uninviting appearance, but 
which in the last year has been greatly improved, has discard¬ 
ed its trade mark, appeared in a clean amber color, free from 
any granules, and whose composition is open to the medical 
and veterinary professions in the published “ ads.” So, it is 
now, in my judgment, a legitimate combination in which tar 
is admirably combined with a petroleum jelly, which in itself 
is not a meagre curative ingredient in the treatment of skin 
affections and wounds. At any rate, I use tarro-petrolene 
largely pure, or with an addition of other drugs, with remarka¬ 
ble success in almost every kind of skin eruptions and even in 
local acute inflammations such as lymphangitis, mammitis in 
cows, in which it has given me great satisfaction. 
In this ointment, tar seems to be dissolved some way and 
not simply mixed with the excipient, and the beauty of it is, 
that it is always ready and one has not to wait a whole day 
foi a pound of bad ointment, if he prescribes it at a drug 
store, or it saves the practitioner mixing and boiling a whole 
day himself to bring forth in the end only a poor mixture at 
best. 
Tarro-petrolene, it is published, contains a little over two 
drams of tar to the ounce and, I think, a trace of boracic acid. 
Any other proper and compatible chemical may be added to 
it in a particular case where it is desirable. For instance, I 
have added carbolic acid, aristol, boracic acid, iodoform and 
particularly naphthol. 
In mange and other skin affections (of a parasitic or non- 
parasitic character) in dogs I have used this successfully with 
and without the addition of sulphur, creosote, etc. Of course 
I have not banished the internal use of arsenic and iodide of 
potassium, but where these and all forms of ointment failed 
