It's a hand percussion masonry drill. Generically known as rawl drills, after the the originating company, Rawlplug, a division of Rawlings Brothers Co., Ltd. of the UK. A rawlplug is a masonry anchor invented by one of the Rawlings brothers in 1909. Originally made of jute fiber bonded with glue, rawlplugs are now made of plastic or metal depending on their intended application. Star tools made these drills as well and apparently made yours. The bit has a tapered end and will become wedged in the handle upon use, thus the cutout in the side of the tool, to insert a drift pin to knock the bit out. Use is pretty simple, insert the correct sized bit for the anchor you are using in the handle, line it up, strike the end of the handle (thus the mushrooming on your example), twist to clear dust and prevent the bit from binding, strike again, repeat until the hole is the correct depth. Missing from yours is a molded rubber, mushroom shaped guard to protect the hand holding the drill from errant hammer strikes. Who would use such a tool these days when you could do the same thing faster with a (cordless) hammer drill? Rock climbers, for one. Some of them carry a drill sized for the bolts they use to set climbing anchors and a short handled hammer to drive it.
