Before a man can successfully plan a structure... he must study, from every possible angle, the ultimate purpose of his building. Attention must be d… - Eduardo Torroja

[E]xperimental investigation of stresses in a plane structure is of great interest and merit as applied to shells with single curvature (barrel shells, pipes) and to shells with double curvature (domes, etc.). In these structures similar states of stress are produced and can be determined at any point as acting in a plane tangential to the center layer of the shell.

Stone can effectively resist compression but is relatively weak in tension. Because of its mass and weight it may be used advantageously in structural types that can be made stable by the proper weight (dead load, gravity) and are but slightly exposed to lateral forces.

Even children know that drafting rule is easier to bend flat than across the edges; and... they will not be much surprised if told that for the same width of the rule its resistance is proportional to the square of the thickness and the deflection is inversely proportional to the cube of the thickness. Nevertheless some modern designers seem to be unaware... since they require... beams of such slenderness that they resemble springboards...