Yes and no. There is the concept of gradient (or slope). Even today you will find that earthworks (of course it depends on coutry regulations) use normally fr

Yes and no. There is the concept of gradient (or slope). Even today you will find that earthworks (of course it depends on coutry regulations) use normally fractions expressing the gradient. You dig (in normal terrain) sections with a 1/1 slope, depending on consistency, harder soil can be excavated with 1/2, 1/3, 1/4 or 1/5 (w/h). You normally create landfillings /for roads, railways, etc.) with 3/2 slopes, which is a very good example how something that is extremely complex expressed in angles, like arctan 2/3, can easily be represented in practice. As well, acqueducts or sewages, railways and roads are usually calculated longitudinally basing on percent (or per thousand) gradient, like 0.1%, 0.5% (h/l). Vertical walls, like the walls built to contain the terrain on the "mountain side" of roads create - if perfectly vertical - the optical effect of appearing "leaning" towards the road, and usually are built with a 5% to 10% "opening" gradient from bottom to top to avoid that effect (and to save concrete), without anyone actually ever calculating the angle at the base.