| 摘要 |
A device assembled from parts unites two common ladders together, one ladder on a roof slope and the other leaning upright towards the eaves. The device and the ladders are one rigid object, and can be moved in one piece. The angle between the ladders adjusts for various slopes. The ends of the two ladders do not meet directly and do not touch a gutter. The roof ladder's tendency to slip down the slope transmits to the foot of the upright ladder pushing into the surface on which it rests, increasing stability. No support from a roof ridge is needed. The climber steps from the upright ladder onto the lowest rung of the roof ladder while holding onto part(s) of the device as handrails. The same device can also fix an upright ladder to the top of a roof ladder, where a wall rises from a roof. <Figure 2>
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