A hand lead line is the device used by mariners before the advent of the modern depth sounders that work on ultrasonic sound waves. It is a length of line with a heavy lead weight on one end and is marked in such a way that the person using the line can see the length of line in the water by looking at the markers. The idea is that the lead is swung around and then let go such that the lead weight is thrown in advance of the vessel dragging the line behind it. The weight sinks into the water and if done properly touches the bottom just as the vessel goes by and the line is straight up and down. The person swinging the lead notes the nearest marker, calls out the depth, pulls in the line coiling as he does so and then repeat the process.
Naiad doesn't have a depth sounder, just a sounding cane and now a lead line.
I bought a job lot of coloured cord ends and used these to mark the lead line I had from my old boat years ago. The lead weight is missing but that is easily fixed. The end pulls were sorted and the line threaded through as shown. Then I stretched the line out in the workshop, moved the markers to the correct places and fixed them in place with a needle and thread.
I only needed 10 metres of line but I left about 50cm at the weight end so that I have enough to tie on the weight when I get it and another 2m at the other end which is the end you hold on to when swinging the lead.
A close up of the markers sewn in place. I used a very strong thread normally used to whip ropes and repair sails, so it shouldn't break easily.
Another task carried out.
I still have to find some suitable white paint for marking the anchor chain.
Time for a cup of tea.