_Essential requisites for continued existence_— An organ of memory, 60 78 Possibility of action in the present, 61 78 _Principle of Continuity_— Illustrated by reference to astronomy, 62-75 79 Breach of the principle illustrated, 76 87 Extension to other faculties of man, 77 88 _Application of this principle to Christian miracles_— Erroneous position of old divines, 78 89 Such opposed to the genius of Christianity, 79 90 New method of explanation, 80-82 90 _Application of this principle to the doctrines of the extreme scientific school_— The visible universe will probably come to an end in transformable energy, 83-84 92 It must have been developed out of the invisible, 85 94 THE UNIVERSE,— 86 95 Similar errors committed by the extreme schools of theology and science, 87 96 _Application of this principle to Immortality_— Three conceivable suppositions, 88 96 These reduced to two, 89 97 Future course of our argument, 90 97 The problem may be profitably discussed, 91 98 CHAPTER III. THE PRESENT PHYSICAL UNIVERSE. Definition of the term ‘Physical Universe’, 92 99 It contains something else besides _matter_ or _stuff_, 93 100 Grounds of our belief in an external universe, 94 101 These in accordance with our definition of the laws of the universe (Art. 54), 95 102 Meaning of conservation, 96 103 [Use and Abuse of the Term _Force_,] 97 104 Conservation of _Momentum_, 97 105 Conservation of _Moment of Momentum_, 97 106 Conservation of _Vis Viva_, 97 107 Definition of _Energy_, 98-99 108 Newton’s second interpretation of his Third Law, 99-100 108 Friction changes work into heat, 101 110 Historical sketch of the theory of energy, 102-103 112 Transformability of energy constitutes its use, 104 115 Case where energy is useless, 105 116