Notes: "The Deci Point was Pickett’s first slide rule, and it was made of magnesium rather than the more familiar aluminum. The Deci Point, copyrighted in 1945, is sometimes called the Picket Model 1. As you would expect, the design of Pickett slide rules was refined and improved over time. The Deci Point was a quite chunky 0.195” thick, while the later models 2, 3, and 4 (still in magnesium) were 0.155” thick. Pickett’s switch from magnesium to aluminum occurred in approximately 1951, and the familiar Pickett “Eye Saver Yellow” color wasn’t introduced until the mid-1950s. While the front of the Deci Point is a fairly conventional slide rule (albeit with double-length square root and triple-length cube root scales), the back contains nothing but elaborate scales for locating the decimal point in your answers. Magnesium corrodes more easily than aluminum, and you will more often than not find early magnesium Pickett slide rules heavily corroded wherever the magnesium is exposed to the air."
