His friend Dr. Black, probably to furnish him with some profitable employment, asked Watt to make a barrel-organ for him, which he at once proceeded to construct. Watt was not the man to refuse work of any kind requiring the exercise of constructive skill. He first carefully studied the principles of harmony,--making science, in a measure, the substitute for want of ear,[70] and took for his guide the profound but obscure work on ‘Harmonics,’ published by Dr. R. Smith of Cambridge. He next made a model of the instrument; after which he constructed the organ, which, when finished, was considered a great success. About the same time the office-bearers of a Mason’s Lodge in Glasgow sent to ask him if he would undertake to build for them a finger-organ. As he had successfully repaired an instrument of the same kind, besides making the barrel-organ, he readily accepted the order. Watt was always, as he said, dissatisfied with other people’s work, as well as his own; and this habit of his mind made him study to improve upon whatever came before him. Thus, in the process of building this organ, he devised a number of novel expedients, such as a sustained monochord, indicators and regulators of the strength of the blast, means of tuning the instrument according to any system of temperament, with sundry contrivances for improving the efficiency of the stops. The qualities of the organ when finished are said to have elicited the surprise and admiration of musicians.[71] [70] General T. Perronet Thompson is another remarkable instance of a person without ear for music, who has mastered the principles of harmony and applied them in the invention of his “Enharmonic Organ.”