His sole work, _Facta et Dicta Memorabilia_, in nine books, is a collection of notable incidents and sayings, classified under appropriate headings, for the convenience of speakers seeking illustrations for their subject-matter. Cf. the preface, 'Urbis Romae exterarumque gentium facta simul ac dicta memoratu digna, quae apud alios latius diffusa sunt quam ut breviter cognosci possint, ab illustribus electa auctoribus digerere constitui, ut documenta sumere volentibus longae inquisitionis labor absit.' The _illustres auctores_ from whom he draws most of his material are Livy, Cicero (each mentioned only once), Sallust, and Trogus; but thirteen Latin and twenty Greek authors are mentioned by name. He frequently misrepresents his authorities. Each book is divided into chapters on separate topics (_e.g._ _De Pudicitia_), under each of which he gives (1) illustrations from Roman history, (2) those from the history of other nations. The latter of course are few in comparison. Although Iulius Paris, the epitomizer of Valerius, speaks of ten books, only nine are extant, and it may be doubted whether there ever was a tenth. Book i. is mutilated. There are only two passages which throw any light on the date of composition--viii. 11, _ext._ 4, a denunciation of Seianus, obviously written after his fall in A.D. 31; and vi. 1 praef., before the death of Livia, A.D. 29. The work was published at latest in A.D. 37, for it is dedicated to Tiberius, who is the object of the most servile flattery (_e.g._ ii. 9, 6); similar language is used of Iulius Caesar (iv. 5, 6), and Augustus (i. 7, 1), while Brutus and Cassius are denounced as parricides (i. 5, 7; i. 8, 8). Two abridgments of Valerius Maximus are extant. CELSUS. Of the life of Celsus nothing is known; but he was an older contemporary of Columella. Colum. iii. 17, 4, 'Iulius Atticus et Cornelius Celsus, aetatis nostrae celeberrimi auctores, patrem atque filium Sasernam secuti.' He wrote an encyclopaedic work on agriculture, medicine, war, rhetoric, and philosophy, but only the section on medicine is extant. Quint. xi. 12, 24, 'Cum etiam Cornelius Celsus, mediocri vir ingenio, non solum de his omnibus conscripserit artibus sed amplius rei militaris et rusticae et medicinae praecepta reliquerit.' The first part consisted of five books on agriculture: cf. Colum. i. 1, 14, 'Cornelius totum corpus disciplinae quinque libris complexus est.' This section of the work was probably written in the reign of Tiberius, for it was known to Iulius Graecinus, whose execution took place under Caligula. Plin. _N.H._ xiv. 33, 'Graecinus, qui alioqui Cornelium Celsum transcripsit.' There are eight books _De Re Medica_. The only indication of their date is in iv. 7, where Celsus mentions a prescription as not found 'in monumentis medicorum.' As this prescription is given by Scribonius Largus, who wrote about A.D. 47, Celsus must have written before that year.