Alan Hart's book aimed to demystify x-rays and radium, making these technologies accessible to a wider audience, including the general public and professionals in related medical fields. Hart, a leading figure in x-ray radiology, compiled his extensive knowledge of tuberculosis and other conditions detectable by x-rays into this comprehensive work.

These Mysterious Rays was translated into several languages, including Spanish, underscoring its global impact. The book serves as a valuable resource for understanding the history and applications of x-rays, particularly in medicine.

Alan Hart was the first known transgender graduate of the University of Oregon Medical School, earning his degree in 1917. His pioneering work on tuberculosis saved countless lives.