I was just explaining to my daughter two weeks ago when we were looking at an old survey map for our place that the old surveys use this measure...but in my head, never having seen the actual chain, I was picturing it like a heavy iron chain of links like you'd use to pull something with a vehicle. So I'm excited to see what the actual surveyor's chain looked like, so different from my mental picture and so much more practical and lighter for hauling around the landscape.
When I was doing environmental field work in northern Ontario, a number of the lakes were identified as 'bottomless' on the old surveys because the method of measuring depth at that time was to lower the chain until you felt it hitting bottom. If the lake was deeper than a single chain (66 ft I think), they linked chains together until they had enough to reach the bottom. Of course, with multiple chains linked together the sensitivity of fishing for the bottom would be reduced and you might not be able to tell, or maybe they didn't have enough chains on hand to actually hit the bottom - those were the so called 'bottomless' lakes.
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Glad you enjoyed it, I though either nobody will get it or someone will get it right away and think fondly of it!
So in response to these surveyors not measuring bellow 20.117m or 66 feet.
I have worked undertaking such surveys with modern equipment and It is not a pleasant experience!
So firstly they would have to pull out the chains tighten them and stay in position, then measure bellow all whilst in a small unstable canoe.
I have several thoughts on the matter as to why they called the lakes bottomless as they did.
1. an agreement with the client as to saving money and time.
2. normally a chain would be stretched out tight and then leap frogged across the line of sight (bearing)
3. accurately measuring water depth with a chain was a rare skill, few surveyors could do it accurately!
4. safety of equipment and people, plus it was without a doubt a horrible experience!
I hope this information helps paint a more "in depth" mental image for you Andrea.
Again Glad that people enjoyed the post!
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