about infrared spectrometry, he was contacted by Paul Rosenberg. Rosenberg worked at MIT's Radiation Laboratory. The lab was part of a secret network of research institutions in both the United States and Britain that were working to develop radar, "radio detecting and ranging". The project was interested in Beckman because of the high quality of the tuning knobs or "potentiometers" which were used on his pH meters. Beckman had trademarked the design of the pH meter knobs, under the name "helipot" for "helical potentiometer". Rosenberg had found that the helipot was more precise, by a factor of ten, than other knobs. Nonetheless, for use in continuously moving airplanes, ships, or submarines, which might be under attack, a redesign would be needed to ensure that the knobs could withstand shocks and vibrations. Beckman was not allowed to tell his staff the reason behind the redesign, and they were not particularly interested in the problem; he eventually came up with a solution himself. Instead of using a wire wrapped around a coil, with pressure from a small spring to create a single contact point, he redesigned the knob to have a continuous groove, in which the contact point was contained. The contact point could then move smoothly and continuously, and could not be jarred out of contact. Beckman's model A Helipot was in tremendous demand by the military. Within the first year of its production, its sales became 40% of the company's income. Beckman spun off a separate company, the Helipot Corporation, to take on the electronics component manufactory. Pauling oxygen meter Linus Pauling at Caltech was also doing secret work for the military. The National Defense Research Committee called a meeting on October 3, 1940, wanting an instrument that could reliably measure oxygen content in a mixture of gases, so that they could measure oxygen conditions in submarines and airplanes. Pauling designed the Pauling oxygen meter for them. Originally approached to supply housing boxes for the meter by Holmes Sturdivant, Pauling's assistant, Beckman was soon asked to produce the entire instrument. While the board of the National Technical Laboratory was unwilling to support the secret project, whose details they could not be told, they agreed that Beckman was free to follow up on it independently. Beckman set up a second spinoff company, Arnold O. Beckman, Inc., for their manufacture. Creating the oxygen meter was a technical challenge, involving the creation of