Step 1: Understanding the Concept:
The question asks to identify the specific ancient text that is often referred to as a "Manual of Dance" due to its focused and detailed treatment of dance techniques.
Step 2: Detailed Explanation:
While the Natyashastra is the foundational encyclopedia for all performing arts, the Abhinayadarpanam by Nandikeshvara is a concise and highly specialized text. It deals almost exclusively with the techniques of dance (Nritta, Nritya, and Natya), with detailed descriptions of hand gestures (hastas), head movements, eye movements, and postures. Because of its practical, focused nature, it is widely considered a primary handbook or "manual" for classical dancers.
Step 3: Final Answer:
The Abhinayadarpanam is famously known as the 'Manual of Dance'.