The Ayurvedic System of Medicine:

 Punarvasu Atreya (about 6th century B.C.) taught medicine at Taxila. Each of his disciples such as Bhela, Jatukarna, Harita, Ksarapani, Parasara wrote treatises on medicine. Atreya himself, Patanjali (about 2nd century B.C.) and later many others wrote commentaries on what is considered  to be the main Indian treatise on medicine, the Caraka-Samhita.  Very little of the original samhita survives today. Most of what we know of  this treatise, comes from some of  these commentaries. The origin of Caraka-Samhita,  ana the surgical text Susruta-Samhita,  is generally estimated to be around 600 B.C. There is difference of opinion as to who wrote these samhitas. While some ascribe them to individrlals, others der-ribe  the authors to be practising doctors and surgeons belonging  to a group of  tribes. The main body of the work is a meticulous classification and documentation of symptoms of various ailments, corresponding healing systems, their properties, methods of application and their dosages. The treatises are so important, because 

i)  thcy sire sc~:pulously  scientific  in their approach and method, 

ii)  that they influence on the development of other branches of  science such as chemistry and botany, and 

iii)  they are transmitted through the ages in a form of practice known as Ayurveda.