The office of these fine implements probably included the excavating of wooden canoes, mortars, and other vessels. Their employment in connection with the mining operations of the Indians has been mentioned. Some specimens exhibit upon their heads the flattening which would result from their being used in conjunction with a wooden mallet, club, stone, or other weighty object. Others show no such marks and were probably employed without such agencies. Rev. W. M. Beauchamp states that a large proportion of the copper articles found in New York are of the celt (axe) or chisel form. Professor G. H. Perkins has described similar implements from New England. At least three distinct types of these implements are known to occur in Wisconsin:— 1. The first of these is broadest at the cutting edge. The edges taper gradually upward from the cutting edge to a pointed, rounded, or squared head. They are usually thickest at or below the middle, the flat or convex surface sloping toward the narrow extremity. Some of these have the upper surface convex and the lower surface flat. The broad or narrow sides may be either convex or flat. Fine implements of this form are to be seen in the H. P. Hamilton, State Historical Museum, and other local collections. A few approach fourteen inches in length. (See Fig. 579.) [Illustration: FIG. 588. (S. 1–1.) Back view of Fig. 587. Milwaukee Public Museum collection. ] 2. A second type is of nearly uniform width throughout, with straight, parallel edges. A specimen in the S. D. Mitchell collection has a cutting edge at either extremity. Implements of this type are to be seen in various Wisconsin cabinets. They range from about five to ten or more inches in length, and from one and one half to two inches in width. (See Fig. 580.) 3. A third and less frequent type is characterized by a more or less prominent median ridge, which traverses its upper surface from within an inch or more of the cutting edge to the opposite extremity. From this ridge the surface bevels off evenly on either side toward the edge. The lower surface is usually flat, thus giving a triangular section. The edges are generally parallel for at least three quarters of the distance back from the cutting edge, whence they taper or curve gradually to the rounded head. A few are of nearly uniform width throughout, with an angular or squared head. Several of these implements have the upper extremity abruptly narrowed and prolonged into a short tang, as if intended to be set into a wooden handle. A few are curved or bowed from extremity to extremity. Some specimens have an expanded, curved cutting edge. One of the largest of these ridged chisels is fourteen and three fourths inches in length. It is in the H. P. Hamilton collection and comes from the town of Oshkosh, Winnebago County. (See specimen to the left, Fig. 579.) _Spuds._ (_See Figs. 581, 583._)