His father, observing the boy's strong bent toward mechanics, placed him for a time as pupil with William Murdock, while the latter lived at Redruth superintending the working and repairs of Boulton and Watt's pumping-engines in that neighborhood. During his pupilage, young Trevithick doubtless learned much from that able mechanic. It is probable that he got his first idea of the high-pressure road locomotive which he afterward constructed from Murdock's ingenious little model above described, the construction and action of which must have been quite familiar to him, for no secret was ever made of it, and its performances were often exhibited. Many new pumping-engines being in course of erection in the neighborhood about that time, there was an unusual demand for engineers, which it was found difficult to supply; and young Trevithick, whose skill was acknowledged, had no difficulty in getting an appointment. The father was astonished at his boy's presumption (as he supposed it to be) in undertaking such a responsibility, and he begged the mine agents to reconsider their decision. But the result showed that they were justified in making the appointment; for young Trevithick, though he had not yet attained his majority, proved fully competent to perform the duties devolving upon him as engineer. So long as Boulton and Watt's patent continued to run, constant attempts were made in Cornwall and elsewhere to upset it. Their engines had cleared the mines of water, and thereby rescued the mine lords from ruin, but it was felt to be a great hardship that they should have to pay for the right to use them. They accordingly stimulated the ingenuity of the local engineers to contrive an engine that should answer the same purpose, and enable them to evade making any farther payments to Boulton and Watt. The first to produce an engine that seemed likely to answer the purpose was Jonathan Hornblower, who had been employed in erecting Watt's engines in Cornwall. After him one Edward Bull, who had been first a stoker and then an assistant-tender of Watt's engines, turned out another pumping-engine, which promised to prove an equally safe evasion of the existing patent. But Boulton and Watt having taken the necessary steps to defend their right, several actions were tried, in which they proved successful, and then the mine lords were compelled to disgorge. When they found that Hornblower could be of no farther use to them, they abandoned him--threw him away like a sucked orange; and shortly after we find him a prisoner for debt in the King's Bench, almost in a state of starvation. Nor do we hear any thing more of Edward Bull after the issue of the Boulton and Watt trial.