| 摘要 |
A Mason's Guide for Aligning Building Blocks consisting of (1) a clamp element having an aperture, (2) a pair of screws extending through the aperture, and (3) having at one end a pair of washers, one of which is a flat washer and the other of which is a dished washer, (4) nuts on one end of each screw and securing the washers against the clamped element, and (5) a cord secured to the clamp by being interposed between the two washers. The aperture is elongated and the clamp element has a channel parallel with and registering with the aperture on one side thereof. The screws extend through the aperture and are slidable along the length thereof. A nut is threaded on each screw at one end thereof and is positioned in the channel. A wing nut is threaded onto the opposite end of each screw for co-operating with the first named nut which is positioned in the channel for clamping the clamp element between said nuts. The cord is secured at the opposite end thereof to a fixed point and at its nearest end to the clamp by it being wound around the screw between the two washers.
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