From: Omens and Superstitions of Southern India by Edgar Thurston, 1912 p. 185:
"Subramaniya yantram, if regularly worshipped, will expel devils from
those attacked by them, and from houses"
Hexagram surrounding a triangle pointing downward (symbolizing water) on the back cover of
Omens and Superstitions of Southern India by Edgar Thurston, 1912
