Polished stone hatchets or celts are supposed to have been made and used before man discovered that a grooved stone was more serviceable and could be securely fastened in the handle. These objects have been the subject of much study. My friend of many years standing, a distinguished archæologist, the late Dr. Thomas Wilson of the Smithsonian Institution, made axes and celts a study covering years. Excepting Professors Holmes and Putnam, there is nobody to-day professionally engaged in archæology in possession of Dr. Wilson’s technical knowledge of the use of stone implements in ancient times. Dr. Wilson knew little about modern tribes, and cared less. He was not an ethnologist, as was Professor Mason, but he had labored for many years in the field in France, Italy, and Spain, was familiar with archæological literature and in full sympathy with the point of view of stone-age man. Men who live in the present rather than the past cannot appreciate this distinction. It is more than a fine distinction, as it is a broad and true distinction. Dr. Wilson, while trained in archæology abroad, was able to catch the correct point of view in American archæology. While his classifications of the celt, axe, chipped stone, and so forth have been enlarged and improved upon in recent years, yet to him belongs no little credit. Dr. Wilson’s papers on the celt and the axe (see Bibliography), and Mr. Willoughby’s article in the _Anthropologist_, June, 1907, p. 296, on the “Adze and Ungrooved Axe of the New England Indians,” are suggested to students for reading. Dr. Wilson treats almost exclusively of the axe and adze and celt in prehistoric times. Mr. Willoughby illustrates prehistoric forms, but cites all the early writers who have made reference to the celt. However, none of these writers are clear as to whether tools used are celts, adzes, hatchets, either grooved or ungrooved. My classification of stone hatchets is as follows:— _Stone Hatchets_ 1. Ungrooved hatchets, or celts. (a) Simple, oval pebble with a sharp edge. (Figs. 219–220.) (b) Triangular hatchets, narrow poll, broad blade. (Fig. 221.) (c) Face almost flat, sides nearly straight. (Fig. 222.) (d) One side or surface convex, the reverse flat. (Figs. 225, 238.) (e) As (d), except that one flat surface is sharply beveled towards the edge. (Figs. 224, 241.) (f) Blade flaring. (Figs. 233, 234.) 2. Adzes and gouges. (a) Slightly hollowed, one side convex. (Fig. 239.) (b) Deeply hollowed. (Figs. 242–243.) (c) Slightly grooved, or with knobs. (Fig. 247.) _Grooved Axes_ (a) Groove entirely encircling specimen. (Figs. 248, 252.) (b) Three fourths grooved; the back flat or hollowed. (Figs. 254, 257.) (c) Grooved and the poll pointed or rounded. (Figs. 263, 265.) (d) Double-edged, or double-bitted—grooved in the centre. (Figs. 274, 283, 284, 299, 300.)