Horse collar of the Oseberg ship burial). The problem with a breastcollar harness was that the actual shafts of the cart, chariot, or other vehicle are attached to a surcingle around the barrel of the horse. The breastplate primarily kept the surcingle from slipping back, not as the primary pushing object. This results in the horse literally pulling the load, a less efficient use of the animal. The modern breastcollar has traces which transfer the pull directly from the breastcollar, but a horse collar still is more effective for pulling heavy loads. After the breastcollar harness, the next and final evolutionary stage
Tree girth measurement just accepted at face value. In these older accounts the girths were often taken at ground level and incorporated considerable basal flare at the base of the tree. In other cases, the trees measured were multiple trunk masses or coppices treated as single trees in the girth measurements. In many, but not all champion tree lists, and for data collected for scientific purposes, there is a need to distinguish between a single trunk tree and a multi-trunk tree. Two smaller trunks that grow together will achieve a large combined girth much faster than will a single trunk tree growing in