Which individual explained the permanence and uniqueness of friction ridge skin through a letter?

The correct answer identifies Sir William James Herschel as the individual who articulated the concepts of permanence and uniqueness of friction ridge skin through his writings, specifically a letter. Herschel's contributions to the field of fingerprinting are significant as he was one of the first to recognize that fingerprints could uniquely identify individuals and remain unchanged throughout one's lifetime.

In his correspondence, he emphasized how friction ridges on fingers serve as distinguishing features, laying groundwork for future developments in forensic science. His observations were pivotal in moving the field beyond mere anecdotal evidence to a deeper understanding of the biological and forensic significance of fingerprints.

Understanding these fundamental principles of permanence and uniqueness is crucial for latent print analysis, as they underscore the reliability of fingerprint identification in forensic investigations. Herschel's insights helped shape the modern forensic fingerprinting methodology, highlighting the enduring nature of each individual's fingerprint patterns.