Sentence:  One of the substances tried was <WSD>castoreum</WSD>....If I were to judge from my own experience, I would say <WSD>castoreum</WSD> has very little therapeutic power, for I have not seen much benefit from its employment in those cases to which this remedy is said to be adapted. 
Meaning of the word marked with <WSD> tags:  The bitter exudate of the castor sacs of mature beavers.