Step 1: Understanding the Concept:
The question asks for the classification of the Harmonium based on how it produces sound.
Step 2: Detailed Explanation:
The Harmonium produces sound when air, pumped by hand-operated bellows, flows past a set of metallic reeds, causing them to vibrate. Since the sound is generated by means of air (wind), it falls under the category of wind instruments. In the Indian classification system, it is a 'Sushira Vadya'. It is specifically a 'free-reed aerophone'.
- String Instruments (Tata Vadya) produce sound from vibrating strings (e.g., Sitar).
- Percussion Instruments (Avanaddha Vadya) produce sound by being struck (e.g., Tabla).
- Metallic Instrument (Ghana Vadya) is a type of percussion where a solid metallic body is struck (e.g., Manjira), which is different from the harmonium's mechanism.
Step 3: Final Answer:
The Harmonium is classified as a Wind Instrument.