In 1889 Sollas became a Fellow of the Royal Society, and was awarded the Royal Medal in 1914. From 1900 to 1902 he was vice president, and from 1908 to 1910 he served as president of the Geological Society of London, who awarded him the Bigsby Medal in 1893 and the Wollaston Medal in 1907. Sollas is known for inventing the serial sectioning device, which made it possible to study the internal anatomy of fossils by removing thin layers of them in cross-section, and capturing the anatomy through drawings and photographs. This method was destructive, but made it possible to study previously unknown internal structures of fossil animals such as ichthyosaurs, and dicynodonts.