 Complete the following phrase:  The first commercial bagpipe makers were prior to 1750 in Edinburgh and Glasgow and skilled musical instrument makers were often wood turners by profession, and began to craft instrument to a design individual to the makers style and innovations. Several well established 18th-century instrument makers are recorded at this time; i.e. Donald MacDonald of Edinburgh and Malcolm MacGregor of Glasgow diversifying and making a variety of pipes. Robertson was no exception and in his designs, added decoration of beading and combing style on Highland bagpipes which in turn was adopted as standard by the late 18th century and has remained unchanged since then. He crafted the Edinburgh prize Great Highland pipe of 1802, which was later played at the 