835. Lintner and Sporborg speed indicator for shafting, patent number 508,686. It's used to determine the number of revolutions made by revolving shafts within a given time.




Here is a different version of a speed indicator that I posted last year:











836. Axle nut wrench, patent number 206,721. From the patent: "...used to take off a nut from a wagon or carriage axle, to allow removal of the wheel, and to screw the nut on again, without any necessity of handling the nut, thereby avoiding the danger of getting sand in the bearing of the wheel or grease upon the hands of the person using the wrench."











837. Ballot box or blackball box, black and white marbles were kept in the open end, a white marble dropped into the hole signified a supporting vote while a black one signified a "no" vote.











838. Fisherman's blood knot tying tool, called a Tru-Blood Knot Tyer.











839. Clock pendulum


5-1/2" long:











840. Mountain climber's piton



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The owner of an unidentified tool sent in a link to a page of photos of it, maybe someone here will recognize this one.




































Last week's set is seen below, click here to view the entire post:








More discussion and comments on these photos can be found at the newsgroup rec.puzzles.