CHAP.		PAGE
XIII.	The relation of water to the other elements. Thales' One of the Seven Sages of Greece. silly notion that the earth sails on water like a ship at sea.	124
XIV.	The Egyptians divide each of the elements into male and female.	125
XV.	The veins of the earth resemble those of the human body. There are likewise analogies of marrow, mucus, etc., and comparisons to injuries, bleeding, birth, and perspiration.	125
XVI.	Intermittent fountains are an illustration of seasonal activity. The great vacant spaces of the earth and their inhabitants. Underground fish.	128
XVII.	The incredible wonders of nature are paralleled and even outdone by the excesses of luxury.	129
XVIII.	The extravagances of luxury, which drive a wise man to madness.	130
XIX.	To return: a sudden eruption of water casts up fish, generally poisonous. This points to an unfailing supply of subterranean water.	132
XX.	The various tastes of water are due to four causes; qualities of water include petrifying, sleep-inducing, intoxicating, and fatal varieties.	133
XXI.	The same pestilential influence that taints rivers is perceived in caves: the noxious rivers flow from or through them.	134
XXII.	The Ocean and seas are as old as the universe. So, probably, are abnormal rivers like the Danube and the Nile.	135
XXIII.	Rain and surface water must be added to subterranean sources.	135
XXIV.	The causes of hot springs.	136
XXV.	Poisonous rivers. The coloring power of others. The great specific gravity of certain waters, its effects and cause.	137
XXVI.	Intermittent rivers and springs. The means possessed by rivers, fountains, and seas to purify themselves.	141
XXVII.	Digression on the universal deluge that will destroy the world. Nature is stingy in creation but lavish in destruction. Ovid is inconsistent in his treatment of this catastrophe.	143
XXVIII.	Further imaginative pictures of what water can do to destroy. Alternative methods of destroying the earth—water and fire.	148
XXIX.	Further possibilities of the same character. Distinctions of seas, gulfs, etc., will all be obliterated; nature and the works of man will alike be overthrown.	150
XXX.	Nature shows, by the chafing of the sea, that she intends to inundate the world. A deluge is part of the foreordained plan. But there will be a new earth and a new race of men who will not sin—for a time.	154

BOOK IV

CONTAINING A DISCUSSION OF SNOW, HAIL, AND RAIN. [THE NILE]

PREFACE

The dangers of flattery and its insidiousness. If you must have praise, praise yourself. Lucilius Gaius Lucilius, to whom Seneca addresses these letters. has good cause: he must not.