I cannot refrain from quoting the words of Cato the censor, which are so pertinent to this point. It appears from them, that even Cato, who wrote commentaries on military discipline[77], and who had learned the military art under Africanus, or rather under Hannibal (for he could not endure Africanus[78], who, when he was his general, had borne away the triumph from him), that Cato, I say, was open to the attacks of such as caught at reputation for themselves by detracting from the merits of others. And what does he say in his book? “I know, that when I shall publish what I have written, there will be many who will do all they can to depreciate it, and, especially, such as are themselves void of all merit; but I let their harangues glide by me.” Nor was the remark of Plancus[79] a bad one, when Asinius Pollio[80] was said to be preparing an oration against him, which was to be published either by himself or his children, after the death of Plancus, in order that he might not be able to answer it: “It is only ghosts that fight with the dead.” This gave such a blow to the oration, that in the opinion of the learned generally, nothing was ever thought more scandalous. Feeling myself, therefore, secure against these vile slanderers[81], a name elegantly composed by Cato, to express their slanderous and vile disposition (for what other object have they, but to wrangle and breed quarrels?), I will proceed with my projected work. And because the public good requires that you should be spared as much as possible from all trouble, I have subjoined to this epistle the contents of each of the following books[82], and have used my best endeavours to prevent your being obliged to read them all through. And this, which was done for your benefit, will also serve the same purpose for others, so that any one may search for what he wishes, and may know where to find it. This has been already done among us by Valerius Soranus, in his work which he entitled “On Mysteries[83].” The 1st book is the Preface of the Work, dedicated to Titus Vespasian Cæsar. The 2nd is on the World, the Elements, and the Heavenly Bodies[84]. The 3rd, 4th, 5th and 6th books are on Geography, in which is contained an account of the situation of the different countries, the inhabitants, the seas, towns, harbours, mountains, rivers, and dimensions, and the various tribes, some of which still exist and others have disappeared. The 7th is on Man, and the Inventions of Man. The 8th on the various kinds of Land Animals. The 9th on Aquatic Animals. The 10th on the various kinds of Birds. The 11th on Insects. The 12th on Odoriferous Plants. The 13th on Exotic Trees. The 14th on Vines. The 15th on Fruit Trees. The 16th on Forest Trees. The 17th on Plants raised in nurseries or gardens. The 18th on the nature of Fruits and the Cerealia, and the pursuits of the Husbandman. The 19th on Flax, Broom[85], and Gardening.