Holmegaard bow

The Holmegaard bows are a series of self bows found in the bogs of Northern Europe dating from the Mesolithic period. They are named after the Holmegaard area of Denmark in which the first and oldest specimens were found, and are the oldest bows discovered anywhere in the world.

The shape of the Holmegaard bows is their distinctive feature, having wide, parallel limbs and a biconvex midsection with the tips ending in a point. The handle is deep, narrow and remains stiff while the bow is drawn. The bows are generally between 150 and 170 cm in length and less than 6 cm wide. The oldest specimens are made of elm and some of the more recent examples are made of yew. The tiller of a Holmegaard style bow is more circular than that of a longbow since only the inner limbs are bending.

Initially, the Holmegaard bows were believed to have been made "backwards", that is with wood removed from the back and the belly made convex. This may be the result of a comparison with the English Longbow that has a flat back and a convex belly. Many successful replicas were made in this fashion even though working the back of the bow cuts the wood fibres and endangers the bow.

Subsequent analysis suggested the back may have instead been convex with the flattened surface being the belly. This is far more efficient for woods like elm which are relatively strong in tension. The compression strain on the belly is evenly distributed on the flat surface which reduces string follow. The yew bows are generally narrower, yew being better suited for narrow bows than elm.

The length of the bow as well as the stiff outer limbs contribute to having a low string angle at the tips. This reduces stacking: the exponential increase in draw weight at longer draw lengths. A lower stacking bow is smoother to draw.

The Holmegaard bow can shoot an arrow faster and farther due to the light, long and stiff outer limbs that act as levers when propelling the arrow. This is the same principle that explains why a dart can be propelled faster from an Atlatl than from throwing alone.

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Wikipedia