What mathematical relationship concerning pitch did Marin Mersenne establish in the 17th century?

Relationship between string's length, tension, and mass

Marin Mersenne, a French polymath active in the early 17th century, is significant because his work marked the true establishment of acoustics as a measurable field, moving it beyond mere intuition. He developed Mersenne’s Laws, which provided a quantitative, mathematical linkage between the physical characteristics of a vibrating string—specifically its length, the tension applied to it, and its mass—and the resulting audible frequency, or pitch. This foundational work, disseminated partly through the printing press, allowed architects and builders to move toward mathematically informed design choices, rather than relying solely on inherited building traditions.