The era anchored biomolecular science in quantitative, measurement-driven approaches, integrating physical chemistry with biochemistry to relate viscosity, electrophoretic behavior, and fractionation patterns to molecular size, weight, and composition. Researchers developed purification and characterization workflows that could isolate and profile proteins and nucleic acids, enabling comparative analyses across biological samples. Methodological diversity—from viscosity analysis to early electrophoresis—created a cohesive framework for linking observable properties to molecular structure. Historical Significance: The breakthroughs of this period seeded the molecular biology revolution by establishing essential analytical tools for macromolecules. Intrinsic viscosity and concentration-dependent viscosity measurements introduced a route to infer biopolymer size and shape; zone electrophoresis and multi-fractionation expanded the capacity to profile and purify biomolecules, shaping proteomics and diagnostics. By estimating DNA molecular weight and size, the period reinforced nucleic acid models and set the stage for subsequent genome-era insights.