THE accompanying engraving shows how a floating reamer can be made and the way it is used. For very accurate work the floating reamer has come to be the standard. This style of reamer the writer has used very successfully on a lathe. Floating reamer for lathe. The reamer is held in a holder as shown, the holder is bored about lfs-inch larger than the body of reamer. This is done so as to allow the reamer free movement. The reamer is held as shown against a center at the ' back and it has a pin through it at B, which prevents the reamer from turning. The hole that is drilled through the holder should provide about lfs-inch clearance, so that the reamer can find its center while in use. There are four springs shown at C which are used to adjust the reamer into alinement with the work. These springs are held in position by means of set screws A. This reamer has now been in service for about two years and is used for reaming draw tubes for telescopes.