596,766. Turning. BOOTH, N. R. Aug. 3, 1945, No. 19945. [Class 83 (iii)] In a tool-holder of the type in which the tool is clamped in a block, means are provided for adjusting the block vertically and for securing it in any position about a fixed vertical axis. The slide a of a tool-saddle is provided with a cylindrical pillar b about which the tool-holder c can be rotated. The holder is split and may be secured to the pillar b by a clamping screw d. A carrier f, comprising side-straps and a bridge, supports the block through a screw g acting against the pillar b, so that the screw adjusts the height of the tool e relative to the work, the final position being secured by a lock-nut g<2>.