§13. Reference Books.--The collecting and arranging of the information gleaned from these sources has been the task of philologists from very early times, but so much has been added to our knowledge by recent discoveries that all but the latest books may be neglected by the student. A very full list of books treating of Roman Antiquities may be found in Hübner's "Bibliographie der klassischen Altertumswissenschaft," and a convenient list in Professor Kelsey's "Fifty Topics in Roman Antiquities with References," but the student should not fail to notice at the head of each chapter the lists of authorities to be consulted in the books specifically mentioned below. These have been arranged in two classes, systematic treatises and encyclopedic works, and the student who lacks time to consult all the references should select one at least of the better and larger works in each class for regular and methodical study. §14. Systematic Treatises: Marquardt, Joachim, "Das Privatleben der Römer," 2d edition by A. Mau. This is the seventh volume of the _Handbuch der römischen Alterthümer_ by Marquardt and Mommsen. It is the fullest and most authoritative of all the treatises on the subject and has a few illustrations. Voigt, Moritz, "Die Römischen Privataltertümer," 2d edition. This is a part of the fourth volume of the _Handbuch der klassischen Altertumswissenschaft_ by Iwan von Müller. It is the latest work on the subject, especially rich in the citation of authorities. Guhl and Koner, "Leben der Griechen und Römer," 6th edition by Engelmann. A standard and authoritative work enriched by copious illustrations. There is an English translation of an earlier edition which may be used by those who read no German. Becker, W. A., "Gallus oder römische Scenen aus der Zeit Augusts," new edition by Hermann Göll. This is a standard authority in the form of a novel. The story is of no particular interest, but the notes and excursuses are of the first importance. There is an English translation of the first edition which may be used with caution by those who read no German. Friedländer, L., "Darstellungen aus der Sittengeschichte Roms in der Zeit von August bis zum Ausgang der Antonine," 6th edition. This is the great authority for the time it covers and will be found to include practically the history from the earliest times of all the matters of which it treats. Blümner, Hugo, "Technologie und Terminologie der Gewerbe und Künste bei Griechen und Römern." The very best description of the arts and industries of ancient Greece and Rome. Ramsay, William, "A Manual of Roman Antiquities," 15th edition, revised and partly rewritten by Rodolfo Lanciani. This includes public as well as private antiquities, but the revision seems to have been but partial and the larger part of the book is hopelessly out of date.