The various preparations of insulin available for prescription vary in onset, intensity, and duration of action. Animal source insulins, pork and beef, have been discontinued in the U.S. market. Human insulin is derived by recombinant DNA technology and is termed quick acting, intermediate acting, or long acting.
The pole lathe was invented sometime before the 13th century AD. Although it represented a great advance the pole lathe was not that much more complicated than its predecessors. The differences consisted of a framework to raise the bed of the lathe clear of the ground, the addition of a pole and a treadle.
In 1789 the Pennsylvania legislature placed an advertisement in English newspapers offering a cash bounty to any English textile worker who would migrate to the state. Samuel Slater, who was just finishing an apprenticeship in a Derbyshire textile mill, read the ad. He went to London, booked passage to America, and landed in Philadelphia. On December 21, 1790, the mill opened. Seven boys and 2 girls, all between the ages of 7 and 12, operated the little factory's 72 spindles.