N
- Nebula, are they parts of our siderial system? [243], [249]; condensation of, [250]; motion in, [251]; significance of forms of, [254]; structure of spiral, [254].
- Nebular hypothesis, [3], [34]; its high derivation, [239]; it explains cometary phenomena, [262].
- Negative facts in geology, small value of, [362]-365.
- Nervous system, effects of excitement in, [195]; directions of discharge of excitement in, [197]; course of discharge unguided by purpose, [201].
- Number, origin of conception of, [154].