Then, in 1776, came Samuel Crompton of Bolton, who invented a combination of the jenny of Hargreaves and the roller water frame of Arkwright, and to distinguish his invention from the others he named it the “mule.” The mule was a carriage on wheels to which the spindles were attached. When the mule was drawn out one way on its frame the rovings were drawn from bobbins through rollers on a stationary frame, stretched and twisted into threads, and then as the mule was run back the spun threads were wound on spools on the spindles. The mule entirely superseded the use of the jenny. Notwithstanding the advantage in names the mule did more delicate work than the jenny. It avoided the continuous stretch on the thread of the jenny by first completing the thread and then winding it. Crompton’s mule was moved back and forth by hand. Roberts subsequently made it self-acting. Next, followed in England the Rev. Edward Cartwright, who, turning his attention to _looms_, invented the first loom run by machinery, the _first power loom_, 1784-85. Then the rioters turned on him, and he experienced the same attentions received by Hargreaves and Arkwright. The ignorance of ages died in this branch of human progress, as it often dies in others, with a violent wrench. But the age of steam had at last come, and with it the spinning machine, the power loom, the printing press, and the discovery among men of the powers of the mind, their freedom to exercise such powers, and their right to possess the fruits of their labours. The completed inventions of Arkwright and others, combined with Watt’s steam engine, revolutionised trade, and resulted in the establishment of mills and factories. A thousand spindles whirled where one hummed before. The factory life which drew the women and girls from their country homes to heated, and closely occupied, ill ventilated buildings within town limits, was, however, not regarded as an improvement in the matter of health; and it was a long time before mills were constructed and operated with the view to the correction of this evil. The great increase in demand for cotton produced by these machine inventions could not have been met had it not been for Eli Whitney’s invention of the saw gin in America in 1793. The cleaning of the seed from the cotton accomplished by this machine produced as great a revolution in the culture of cotton in America as the inventions of Arkwright and others accomplished in spinning and weaving in England. America had also learned of Arkwright’s machinery. Samuel Slater, a former employee of Arkwright, introduced it to Rhode Island in 1789, and built a great cotton mill there in 1793. Others followed in Massachusetts. Within twenty years after the introduction of Arkwright’s machines in the United States there were a hundred mills there with a hundred thousand spindles.