These are actually still pretty handy though I didn't know their name! I used them in a chemistry class where various partial pressures were calculated and the various axis were included for O2, H2, etc. Nomogram's are often quicker than even looking up similar information on a computer. It seems sometimes we've lost the ability to quickly and intuitively solve problems without resorting to a computer. These graphical methods allow you to estimate results in your head using even a rough visual memory of the graph.