Duncan MacRae was not a piper however he used his considerable skills and imagination to create an enduring bagpipe. He first appears as a bagpipe maker in the Glasgow business directory in 1909.
This is a great picture, to the right, showing MacRae's hempless tuning slides. By tapping on the top of the slide, the fluted sides expanded, creating a surface that held the tenor top in place. An Alexander Glen bottom section is also shown.
See PM Willie Gray's full silver MacRae bagpipe here. You'll notice that it has threaded stocks and wooden bolts instead of the typical ty-in. This is an innovation that never quite caught on. It also has a threaded bass top, as it pictured above.