The Positive Sciences of the Ancient Hindus c4.s6.26.6

c4.s6.26.6

विरलतेजःसम्बन्धीनि द्रव्यगुणकर्म्माणि छाया इत्यभिधीयते । सङ्गेतो व्यावृत्ततेजःसम्बन्धीनि तु तानि तमःसंज्ञकानि ।**—Udyotakara, Chap. IV., Áhnika 2, Sutra 25. For reflection and its laws, I quote passages in my Paper on Hindu Physics, to which the student of the history of Optics is referred.)