During holiday times, the boy sometimes indulged in rambles along the Clyde, occasionally crossing to the north shore, and strolling up the Gare Loch and Holy Loch, and even as far as Ben Lomond. He was of a solitary disposition, and loved to wander by himself at night amidst the wooded pleasure-grounds which surrounded the old mansion-house overlooking the town, watching through the trees the mysterious movements of the stars. He became fascinated by the wonders of astronomy, and was stimulated to inquire into the science by the examination of the nautical instruments which he found amongst his father’s shop-stores. For it was a peculiarity which characterised him through life, that he could not look upon any instrument or machine without being seized with a desire to understand its meaning, to unravel its mystery, and master the rationale of its uses. Before he was fifteen he had twice gone through with great attention S’Gravande’s ‘Elements of Natural Philosophy,’ a book belonging to his father. He performed many little experiments in chemistry, and even contrived to make an electrical machine, much to the marvel of those who felt its shocks. Like most invalids, he read eagerly such books on medicine and surgery as came in his way. He went so far as to practise dissection; and on one occasion he was found carrying off for this purpose the head of a child who had died of some uncommon disease. “He told his son,” says Mr. Muirhead, “that, had he been able to bear the sight of the sufferings of patients, he would have been a surgeon.” In his solitary rambles, his love of wild-flowers and plants lured him on to the study of botany. Ever observant of the aspects of nature, the violent upheavings of the mountain-ranges on the north shores of Loch Lomond directed his attention to geology. He was a great devourer of books; reading all that came in his way. On a friend once advising him to be less indiscriminate in his reading, he replied, “I have never yet read a book without gaining information, instruction, or amusement.” This was no answer to the admonition of his friend, who merely recommended him to bestow upon the best books the time he devoted to the worse. But the appetite for knowledge in inquisitive minds is, during youth, when curiosity is fresh and unslacked, too insatiable to be fastidious, and the volume which gets the preference is usually the first which comes in the way. Watt was not, however, a mere bookworm. In his solitary walks through the country he would enter the cottages of the peasantry, gather their local traditions, and impart to them information of a similar kind from his own ample stores. Fishing, which suited his tranquil nature, was his single sport. When unable to ramble for the purpose, he could still indulge the pursuit from his father’s yard, which was open to the sea, and the water of sufficient depth at high-tide to enable vessels of fifty or sixty tons to lie alongside.