Meteorology

BOOK III

CHAP.
1. The causes of, and difference between, ecnephias a wind-driven storm, typhon whirlwind, and prester fiery whirlwind. The kinds of thunderbolt.
2. The causes and concomitants of halos.
3. Why halos are circular, and what they indicate.
4. The rainbow—how it is produced by reflection, and the causes of its properties (e.g. its colours). How it differs from the halo.
5. Some properties of the rainbow.
6. The causes of rods and mock suns.

BOOK IV

1. Hot and cold are active, dry and moist passive principles. True or natural generation is due to these. The contrary of true generation is putrefaction. Putrefaction further considered.
2. Concoction and inconcoction.
3. Three kinds of concoction—ripening, boiling, broiling; and their contraries.
4. Dry and moist, and the properties consequent on them in composite bodies—hard and soft.
5. Every well-defined body must be hard or soft, and solid. Solidification and its causes.
6. Things that can be solidified are made either of water, or of earth and water. Various modes of solidification and solution.
7. Things are thickened by fire or by cold according as they have more water or earth in them.
8. The properties of composite bodies—nineteen positive and nineteen negative. What can and what cannot be solidified; what can and what cannot be melted.
9. The remaining seventeen properties.
10. Homoeomerous having uniform parts or substance bodies.
11. Which mixtures are warm and which are cold.
12. Homoeomerous bodies are composed of the elements. End and function more evident in non-homoeomerous bodies than in the homoeomerous bodies which compose them, and in these than in the elements.