Yesterday I was reading a little more about hook ladders. The hook ladder is a masterful piece of lateral thinking: You cannot carry a ladder long enough to reach where you want to go? Carry enough to reach a ledge or balcony. Climb up to that and then use the ladder to reach higher. A typical ladder would be 4 metres/ 13 ft long.
Here are some videos of hook ladders in action, and even being used for races.
It just so happened that the same day I came across this image. If provision is made to carry or retrieve the painter’s pole such a device can be used to “climb in instalments” in the same fashion as the hook ladder is used.
The “frost knot” is simply an overhand knot. Here is a video on it, and one on making an etrier.
Below are some images of the ninja kumade, effectively a folding hook ladder.