The early Scandinavian or Norse fastenings had a distinct quality. They were not invented, but grew. They were made of one same material throughout, showing the essential feature of a sound binding: uniformity of texture. But the ski-blade was directly fastened to the foot, more particularly to the toes, by the binding.
The defect of these original bindings came to light when they were put to more athletic uses. They then proved too weak, and not sufficiently durable, in the hands of Germans, Austrians, and Swiss, practising the Norse sport in their own countries.
Iron and steel, in varying degrees of hardness, were pressed into service. The uniformity of material was thus brought to an end.
To make a long story short, the Huitfeldt and Ellefsen bindings are generally admitted to be the most useful. The former is distinguished by a clamp for bolting down the heel-strap. The latter obtains rigidity—which is considered indispensable—by binding the heel of the runner to the ski-blade by means of a stiff sole.
Whatever the binding, the mechanics controlling the linking together of limb, boot, and ski in common action, need some explaining. Even the lay-reader may gain some benefit from a short and easy excursion in the domain of technique.
The foot consists of toes, ball, and heel. The point of play is the same, whether one walk or use ski. It lies across the ball of the foot. It is determined by the structure and articulations of the foot, from the extremity of the big toe to above the ankle-joint. But the line of play does not lie along the foot; it lies athwart. On this line turns or hinges the foot, as though a rod were run through it, whether the motion be up and down—that is, vertical; or horizontal (right and left); or oblique (foot sideways and edgeways), as in turns, swings, &c.
There is thus an axis of rotation through the foot. This axis need no more be horizontal than, for instance, the wheels of a motor-car when one drives over an obstacle.
The foot should sit at ease in the binding. It must not be fretted, chafed, galled, or pressed by the material of the binding when the work to be done puts a long and enduring strain on the boot. To that effect, the binding should be such that the pressure will, as it were, cancel itself by an equal application and even distribution, whatever may be the movements and position of the foot.
In other words, the heel-strap must have its point of attachment on the axis of rotation across the foot, the point on which it revolves to describe some portion of a circle in the vertical direction.