Light
स्फटिकाद्य्-अन्तरितोपलब्धिर् अपि
प्रसाद-स्वभावतया स्फटिकादीनां तेजोगतेर् अ-प्रतिबन्धकतया
प्रदीप-प्रभेवोपपन्नेति।
- उदयनः, किरणावली, तेजःप्रकरणम्
“The reason why one can see through crystal & so forth is because these substances have prasāda (transparency/purity), due to which they do not hinder the movement of light (passing through them).”
- Udayana (~10th century CE), Kiraṇāvalī
Magnetism
Bhāsarvajña (~10th century CE) imagined that a magnet changes the vāyu (loosely translated as ‘air’) around itself due to which the air also acts like a magnet and attracts the things which are within its purview.
Bhāsarvajña on how a magnet attracts iron :
“The vāyu dravya attached to the magnet becomes a different kind,
and this vāyu then pulls the iron toward the magnet.”
Note the similarity of his explanation with that of an electromagnetic field.
Ref: Nyāyabhūsaṇa (prāpyakāritva)