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.
Tom Boyer at work in the Foundation shop. Tom is using the Bridgeport mill. Behind the red tool box in the foreground is the Shopfox 14 x 40 lathe. To the right is the Nikon Comparitor and Starrett surface table. Behind the lathe is a Deckel pantograph mill.(Click on photo to view a larger image. milling machine differs from a lathe in that the part does not turn, rather it is mounted firmly in a vise or held to the mill table while a spinning cutting tool secured in the powered spindle is moved into the part. The most common cutting tool used is called an end mill.