Robert William Boyle was one of the pioneers in the development and application of ultrasound. His remarkable career has not been previously traced in any depth, nor have his contributions, especially those during WWI, been carefully described. In collaboration with Lord Rutherford, his work on the development of ultrasound methods for submarine detection paralleled those in France under Paul Langevin (1872-1946), who many consider to be the father of modern ultrasound. This biographic account of Boyle's life focuses on his ultrasound research contributions, particularly the developments during WWI and those in the 10 years after. Evidence is presented that his pioneering research, along with that of Langevin, provided much of the foundation for modern ultrasound developments. Although this paper is partially based on somewhat dispersed biographic information performed by others, original letters and research papers, in addition to records and verbal accounts provided by relatives, have been used and consulted.