First Spectacles ‘Upanetra’ by Adi Sankaracharya in 5th century BCE
Adi Sankaracharya (509 – 477 BCE) has used ‘Upanetra‘, which were eyeglasses used to achieve magnification effect. In his work ‘Aparokshanubhuti‘ (Direct Experience), 81st verse, Sankara states : ‘Just as all objects that are very small appear … Read more