Resonance happens when the vibrations of the air column meet one of the singing rod's inherent frequencies.
Resonance always produces a large vibration, i.e. a loud sound.
Galileo discovered forced vibration and resonance in the 17th century, however, he misunderstood it.
Then, in the 18th century, Euler rediscovered it.
In the second quarter of the nineteenth century, Felix Savart, a French scientist, invented this apparatus to demonstrate resonance. exemplify resonance