By Joseph A. McGeough
The axe and adz are similar enough to be considered together. This is especially the case with ancient tools that were small and ineffective because they were made of brittle stone or had unsatisfactory hafting. The difference between the tools lies in the relation of the cutting edge to the handle. In the axe the cutting edge and handle are parallel, whereas in the adz they stand at right angles. The axe and some adzes chop diagonally across the grain of the wood, but the developed adz, with its long handle, cuts with the grain, and the nature of the chips is quite different. The axe is used for felling or cutting through, whereas the adz is used for smoothing and levelling, although some forms were developed to scoop out gutters or to dig out logs to make canoes. The adz was often shorter handled than the axe and, because of this, was essentially a chipping tool rather than the shaving tool it became when the handle was lengthened. The great problem of both tools is satisfactory hafting; the shock impact between the tool head and handle threatens any type of connection, however ingenious.
The Celt, a smooth chisel-shaped tool head that formed either an axe or adz, dates from the invention of agriculture and the domestication of animals. The earliest true axe heads, made of fine-grained rock with ground edges, are of Swedish provenance and date from about 6000 BCE. Even earlier, self-handled axes, made of reindeer antler, were used. The brow tine, an antler branch running nearly at right angles to the main stem (beam), was sharpened, giving a small axe with a haft of about 20 cm (8 inches). By sharpening the tine, the other way, a tiny adz was created. Some of these small bone implements have survived as the Lyngby tools, named from a Danish site of perhaps 8000 BCE.
A subsequent design socketed a stone blade in a short length of antler that was perforated for a handle. This Maglemosian style, from a Danish site of about 6000 BCE, was a popular model for several thousand years despite its narrow cutting edge and length of about 50 cm (20 inches).
The desire for a better feel or a longer cutting edge, or perhaps the shortage of antlers, led to a great variety of haftings. A common arrangement involved lashing heavy Celts to knee-shaft handles made from branched tree sections. To permit the use of larger Celts, the stone was sometimes fitted into a wooden handle, but this created the danger that the handle would fail due to the weakening hole. Heavy club like handles with ample strength at the hole gave the tool an unfavourable balance.
Surviving examples of Celts of soft stone are believed to have been restricted to non-woodworking axes, used for killing game or perhaps for certain ritual purposes. Hard-stone axes with shaft holes, often obvious imitations of bronze axes, are associated with the Bronze Age. They are among the supreme examples of stone working and are products of the pecking technique. From their delicacy it may be inferred that these axes were not for the working of wood.