Or the tremendous discovery of the correlation and conservation of forces, the identity and convertibility of heat and force and motion, and that no ounce of power is lost, but forever passed along, changing form but not essence, is a poetic discovery no less than a scientific one.
"Birds and Poets"
John Burroughs
Unquestionably the facts and experiments above mentioned show the very near affinity of hornblende and augite; but even the convertibility of one into the other, by melting and recrystallising, does not perhaps demonstrate their absolute identity.
"The Student's Elements of Geology"
Sir Charles Lyell
Xenophanes saw the grandeur and incomprehensibility of the universe, he violently opposed what seemed to him the disgraceful polytheism of Homer, and anticipated the modern atomic theory and the doctrine of the unity of life as revealed by the spectroscope and the discovery of the conservation and mutual convertibility of forces.
"The Three Heron's Feathers"
Hermann Sudermann