Complex sentence: Justice Harlan Stone, writing for the Court, held that the law was "presumptively constitutional" properly within legislative discretion, and hence was not for the courts to overrule because it was supported by substantial public-health evidence, and was not arbitrary or irrational.
Split into simpler sentences: Justice Harlan Stone, writing for the Court, found that the law, being "presumptively constitutional" was essentially a legislative judgment, and hence was not for the courts to overrule. Applying rational-basis review, the Court held that the law was supported by substantial public-health evidence, and was not arbitrary or irrational.