— 131 — 
these experiments, could only confirm our results. The esters of campho- 
carbonic acids have a feeble stimulating action, but up to now have not 
been employed. On the other hand, camphoric acid, Acidum camphoricum, 
has justly been incorporated in the medicinal treasure, as, in addition 
to a faint camphor-like action, it has undoubtedly the effect of coun- 
teracting sweating in phthisics. (Compare p. 120.) As several essential 
oils contain borneol, I also examined this substance with Lap in i). We 
were able to determine that it also represents a stimulant of the central 
nerve-system and the heart. If Borneo-camphor were less expensive 
here, borneol might possibly be able to compete with ordinary camphor. 
We also found a characteristic camphor -action in the acetic ester of 
borneol 2). This is explained by the fact that this ester in the organism 
splits off borneol. The action of menthol^), which was examined at 
the same time for comparison, was totally different, inasmuch as the 
central nerve-system was rapidly paralysed by this substance. But the 
terpenes^), which, in addition to menthol, are contained in oil of pepper- 
mint, act as excitants, as we have also proved. 
Whether the cramp -exciting action of thujone may be used thera- 
peutically, is an open question. 
15. Group of Sedatives and Narcotics. 
Ointments and liniments containing oil of peppermint (already repea- 
tedly mentioned above) have only a local cooling and pain-allaying action 
on inflamed parts of the skin. The remaining cooling ointments 
{Unguenta refrigerantid) exert their refrigerating action by evaporation 
of water, but they mostly also contain a substance having the character 
of an essential oil. Thus, the favourite cold cream [Unguentum leniens) 
belonging to this class contains rose - water. Whether, when a 
warmed pouch with aromatic herbs {Species aromaticae) is placed on 
the swollen cheek in toothache, such a quantity of essential oil pene- 
trates into the skin, that it can thereby affect the inflammation or the 
pain, is a matter which cannot be decided, as the heat which is emitted 
acts at the same time. But it is a fact that common people still cling 
to this treatment in toothache, mumps, swollen lymphatic glands, etc. 
Of internal sedatives, I have at all times recommended valerian to 
the audience at my lectures, as a by no means antiquated or value- 
less remedy. Like alcohol, valerian has also an exciting as well as a 
sedative action. In the form of an infusion (from Radix Valerianae), 
or drops [Tinctura Valerianae), this non-toxic remedy produces in the 
^) Compare also Lap in p. 108. 
2) 1. c. p. 108. 
^) I. c. p. 124. 
I. c. p. 200. 
9* 
