Sentence:  Dr. Wise ... mentions two systems of Hindu surgery and nine systems of medicine, three of materia medica, one of <WSD>posology</WSD>, one of pharmacy, and three of metallic preparations alone. From these one can gather the strength and dimensions of the scientific knowledge of ancient India regarding therapeutic agents of both organic and inorganic origin. 
Meaning of the word marked with <WSD> tags:  The study of the dosages of drugs, "especially" the determination of appropriate dosages. (from 19th c.)