For the hand
Handrails and guardrails at stairs or level changes offer a particular moment in buildings in which we purposefully touch the architecture. The intent of the architect is clearly apparent in these assemblies, and this interaction between visitor and detail can commonly be memorable.
In this example from the Salk Institute, the connection of the handrail to the square baluster bars is by a concealed weld. The square stock is the only component that is allowed to transition from diagonal to horizontal, turn corners, and return to the ground. The graspable surface of the handrail only exists in straight segments parallel to the stringer. The handrail itself is a stainless steel angle that has one of the legs tipped with a solid stainless steel bar; welded and ground clean to unify the two components. The round bar is small; too small by current code requirements and is not particularly comfortable to grasp. However, in lieu of a firm grip the hand gently pinches and glides along the surface of the angle leg. The patina from the oils of numerous hands is evident in the touch and even in this image.