Musical pillars made of solid granite
The Vitthala Temple in the south Indian city of Hampi is more than 500
years old. The image here shows its most curious feature—numerous pillars,
each of which includes separate columns that sound musical notes when
struck with a finger. Different columns in a pillar produce sounds of
different frequencies. Moreover, several multi-columned pillars make sounds
similar to specific Indian musical instruments such as the ghanta
(bell),
mridanga (percussion), or veena (strings). Well known for centuries, the
musical pillars are only now beginning to be studied scientifically. Anish
Kumar of the Indira Gandhi Center for Atomic Research in Kalpakkam, India,
and colleagues took the first steps to characterize the columns: The
physicists applied three techniques to learn about the structure of the
columns and also analyzed recordings of generated sound. In situ
metallography showed the granite to have typical microstructures; both
low-frequency ultrasound and impact-echo testing revealed all the columns
researchers conclude that the pillars’ sounds arise from the flexural mode
of vibrations. Next on their agenda is to study how the columns can be
excited by just the tap of a finger. (A. Kumar et al., *J. Acoust. Soc.
Amer.* *124*, 911, 2008.) — Stephen G. Benka
http://www.poetryinstone.in
“*Here the language of stone surpasses the language of man*” – Nobel
laureate, Rabindranath Tagore
On Sat, Jan 7, 2012 at 11:03 PM, vancheeswaran gopal
