Introduction. --Dialectics. --Basic forms of motion. --The measure of motion--work. --Heat. --Electricity. --Dialectics of nature--notes. --Tidal friction, Kant and Thomson-Tait on the rotation of the earth and lunar attraction. --The part played by labour in the transition from ape to man. --Natural science and the spirit world [from a manuscript of Engels probably written in 1878, and first published in the "Illustrierter neue welt-kalender fèur das jahr 1898"]--Appendices: I. Notes to Anti-Dèuhring, hitherto unpublished in English. II. Source references (p. 329-370). --Bibliography (p. 371-375)--Index.