[Varley]

Now, talking of knots.

An old master on his final trip calls at a dockside pub much frequented in his more junior days. After being astonished at the price of a pint he idly wonders if the young ladies still plied their trade in the accommodations 'above'. They did and although astonished again at the tariff he decides that as it's his last call he will sample the goods.

Well aware he was no longer the golden youth that the girls had vied for but still proud (if not vain) he asked the dug-out old maid, who had drawn his short straw, "How he was doing".

"Well", says the old trooper. "You're doing three knots, Captain".

"Three knots, how d'yer work that out?"

"Easy" says she "You're not hard, not in and you're not getting your money back!"

Dredging.

We need a belly-button draughtsman to confirm but I think the reason dredging doesn't work is that deepening the depth under keel will reduce tendency to squat.

If one were tramping (full-away plus) under the Yarra Bridge with just enough Yarra underneath to remain seaborne then squat would result in more airdraught. Of course there is a good chance that one pushes sufficient Yarra water out of the way to allow her to tear herself open on Yarra bed which is not as buoyant as Yarra water (assuming antipodean water to be as floationally similar to Douglas river water) or as forgiving in terms of what it does to formerly double bottoms when encountering them at speed.

Dredging will result in conditions less conducive to squat and so reducing airdraught. In this case raising the bridge might be a better option to avoid conjoining of the two bridge decks. Meanwhile, take a pilot.

I should say the squat here is not related to the toilet paper procurement conundrum of earlier in the thread. Not, that is, unless the arithmetic lacks the necessary precision required to employ squat to avoid either of the two immediately unfavourable outcomes of such a plan.