The name Stonehenge provides a clue. Although 3000 years later, the term 'henge', was derived from the Middle English words Heng, 'hang', and 'hing', and for reasons unknown it was assigned to the vestiges of the monument. It prompts the notion of something hanging by rope beneath the beam. Twenty eight beams for such arrangements around the sarsen circle suggests observations directed at the sky, possibly utilising stripped, straight, tree stems impaled by a flint at each end to form sights. These would be analogous to those of a rifle, the stem being slung in a controlled way. This was possible because inwards of the circle and either side of each gap stood a small upright stone about 1.4m (4.5ft) tall, ideal as a bollard for securing ropes, Figs 9, 13, 14.
Fig. 9 Stone henge entrance from within, showing its rebated spacer beam 101, and tongue of beam 130
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Fig. 13 Sections through the installation: (schematic)
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Fig. 14 Proximate model of the Stone henge's aim-design
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Three lengths of rope would have been needed. The loop of one could have been thrown outwards over the beam to be wrapped off-centre round the stem, such that its outward, smaller end rested on the ground outside the circle. Each end of the rope would be tied to a bollard. The centre of the second rope was tied to the stem's butt, each end being passed through the gap, then round its adjacent upright to be secured to the bollard behind this. This was after being tensioned to pull the butt downwards and forwards, thus raising the stem's smaller end towards the sky. This rope controlled the stem's slope, or angle of elevation. The third rope was also tied to the butt but its ends were passed outside the uprights, to come round and back through the gap before being secured to the bollard. By slackening and tightening these runs in concert, to some extent the stem could be orientated in various directions to left and right.
The greatest achievable angle would have been 30-40 degrees, more than this would render the arrangement unstable. A hoist rope was needed for higher angles; this was provided for stations in five groups of three, Fig 14. Inwards of each group were erected two much taller uprights with only a narrow space separating them, and surmounted by a horizontal beam. Over this ran a long rope, outwards above the circle and tied to the stem's small end; inwards and immediately downwards to be entwined clockwise, or anticlockwise around one or other of the tall uprights, this before being secured to one or other bollards located further inwards. These tall uprights with their beams are conventionally named trilithons, but here they will be called masts.
For the hoist rope to work smoothly, the roughness of the top surface of the beam, and its corners had to be overcome. This was achieved by placing along the beam a baulk of timber greased with animal fat after removal of its bark The means of securing the baulk is evident on the fallen beam of the tallest mast to southwest:. Towards each end is a recess into which fitted a small protrusion, or lug, fashioned on the flat face when the baulk was made a half-log. The downward pressure of the rope ensured the baulk's, or runner's, stability. These recesses are absent on the other four masts and it is assumed some alternative had been devised, maybe smaller but whole baulks, mounted on the beam with supports, or cradles.
When contemplating these arrangements one can see that the stresses arising from their use are compatible with the design of the structure and the term 'installation' now seems more appropriate than 'monument', with 'spars' rather than 'tree stems', 'lines' and 'hoists' instead of 'ropes', 'stations' for 'gaps'. To this point we have been concerned with what the designers intended, or the aim-design, not the final result, nevertheless the question now, must be what they intended should be done with it.