The Law of Insurance: As Applied to Fire, Life, Accident, Guarantee, and Other Non-Maritime Risks

Parsons served as the editor for the third edition, which the title page describes as "revised, analyzed, and greatly enlarged" by him . His editorial work expanded the scope of May's original treatise to include life and accident insurance alongside fire and guarantee risks. The edition runs to two volumes totaling lxxiv + 1463 pages, with a table of cases spanning pages xv–lxxiv . This was substantive legal scholarship—Parsons reorganized the material, added new doctrinal analysis, and updated the case law to reflect developments since the previous edition.

John Wilder May (1819–1883) was a Boston jurist and legal author whose original Law of Insurance was first published in 1873 . By the time of the third edition in 1891, May had been dead for eight years, and his treatise required updating to remain current. Parsons, a lecturer at Boston University School of Law, was a natural choice: he had trained as an engineer at Cornell, practiced law, and established himself as a meticulous legal researcher and writer. His revision ensured May's work retained its authority while incorporating a decade of new case law and statutory developments.

The fact that it reached a third edition, published by Little, Brown—then as now a leading legal publisher—indicates its established reputation . Multiple major law libraries hold the 1891 edition, including Yale, the University of Chicago, and the Supreme Court Library of Queensland . It was later digitized for the HeinOnline Legal Classics Library and the Making of the Modern Law series, confirming its status as a canonical American legal text . A 2022 print-on-demand reissue further attests to its continued reference value .

The Law of Insurance belongs to Parsons's first career as a lawyer, legal scholar, and social reformer. He was a lecturer at Boston University School of Law from 1892 and authored works on currency, monopolies, and railroad regulation before turning to vocational guidance in 1907. Choosing a Vocation was published posthumously in 1909. The insurance treatise demonstrates the systematic legal analysis and meticulous research habits that Parsons later applied to social problems. His biographer Richard Gummere described him as "a challenging example for counselors today as both a social crusader and a pioneer in the systematic guidance of youth."

The treatise addressed "non-maritime risks"—fire, life, accident, guarantee, and related lines—deliberately excluding marine insurance, which was governed by a distinct body of law and custom . This scope reflected the structure of nineteenth-century American insurance practice, where marine insurance retained its own specialized legal treatment while inland and life insurance had developed into separate commercial fields requiring their own doctrinal synthesis. Parsons's analysis organized this sprawling material into a coherent framework, making the work usable by practitioners across multiple insurance lines.