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Odd Lots


  1. We toured the Paris Sewer Museum just a couple of months ago. The sewer-cleaning balls on display are not models, they are full-size, and according to my recollection of the accompanying text they are still in use. However, the author of the page you linked to got the balls’ function wrong. They are not used to smash against obstructions but to clear the gunky mixture of sewage and sand (called “batard” [bastard] in French, but referred to as “hybrid material” in the English signage) that accumulates at the bottom of the pipe. The ball, which is just slightly smaller than the pipe, floats to the top of the pipe (the small ones are wood, the big ones are hollow iron) and the restricted flow of water beneath it pushes the ball along and flushes out the gunk, pushing the gunk to the next available clean-out trap.

  2. Mike Brown says:

    There were air rifles earlier than 1779. At Blair Castle in Blair Atholl, Scotland, they have a number of them on the wall in the entrance hall which used brass globes to store the air. They could be fired five or six times before you had to pump them up again. Interestingly, each is equipped with a flintlock mechanism which isn’t connected to anything. Apparently, it was considered unfair to use a gun which didn’t have a big flash and smoke to show where you were shooting from, so these guns had the false flintlock to disguise their nature.

  3. RH in CT says:

    I’ve been avoiding The Hobbit. As much as Jackson’s LOTR impressed me, what I appreciated most was how little he tinkered with the story. Leaving out Bombadil completely was forgivable and understandable. Leaving out the Scouring of the Shire was less forgivable but somewhat understandable. But very little was added. To turn The Hobbit into two films required adding rather a lot it would seem, and just the thought of that bugs me enough I have put it off in favor of waiting for the disks.

    1. Well, he turned it into three films, actually, one of which we have yet to see. Some of that is padding, or CGI showing-off (e.g., the rock giants) but some of it is a reasonably smooth melting-in of background elements that Tolkien didn’t mention in the novel itself. We see Radagast, and Gandalf’s trip to Dol Guldur. The Tauriel character was something Jackson invented, and while she works well in context, I can understand why people object, including some who feel she was tossed in for “romance” and mostly wasted as a character. Parts of the first two films drag here and there, and if the whole weren’t so sumptuous (especially the footage inside Erebor in the second film) I wouldn’t be as enthusiastic as I am.

  4. Stickmaker says:

    Air rifles saw serious military use, including during the Napoleonic Wars. They had nearly the range and effect of black powder rifles and the best ones had a much higher rate of fire.

    Users carried a pump and several spare reservoirs/stocks. Those would be filled ahead of time, and each could provide several full-powered, carefully metered and consistent shots. The weapons were breech loaders. Just open the hatch, pop the bullet in the chamber, arm and pull the trigger, safe and repeat.

    Makes you wonder why the NSA or whoever isn’t developing “pneumatic stealth weapons” for today. 🙂

    1. How good were pressure vessels of the time? How long could they hold a charge? I’d have to guess that all the joints were filled with solder. The machining tolerances of that era were not spectacular. See:

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