The appointment was well-timed in the interest of the Society, for the experience he had obtained as an officer in the Surveying Expedition of Captain Stanley rendered his co-operation and advice of the greatest value in the efforts which the Society had recently commenced to induce the Government, through the Admiralty especially, to undertake the physical and biological exploration of the ocean. It was but a few months before his appointment that he had been placed upon a committee of the Society, through which H.M.S. "Porcupine" was employed for this purpose in the European seas, and negotiations had already been commenced with the Admiralty for a voyage of circumnavigation with the same objects, which eventuated in the "Challenger" Expedition. In the first year of his appointment, the equipment of the "Challenger", and selection of its officers, was entrusted to the Royal Society, and in the preparation of the instructions to the naturalists Mr. Huxley had a dominating responsibility. In the same year a correspondence commenced with the India Office on the subject of deep-sea dredging in the Indian Ocean (it came to nothing), and another with the Royal Geographical Society on that of a North Polar Expedition, which resulted in the Nares Expedition (1875). In 1873, another with the Admiralty on the advisability of appointing naturalists to accompany two of the expeditions about to be despatched for observing the transit of Venus across the sun's disk in Mauritius and Kerguelen, which resulted in three naturalists being appointed. Arduous as was the correspondence devolving on the Biological Secretary, through the instructing and instalment of these two expeditions, it was as nothing compared with the official, demi-official, and private, with the Government and individuals, that arose from the Government request that the Royal Society should arrange for the publication and distribution of the enormous collections brought home by the above-named expedition. It is not too much to say that Mr. Huxley had a voice in every detail of these publications. The sittings of the Committee of Publication of the "Challenger" Expedition collections (of which Sir J.D. Hooker was chairman, and Mr. Huxley the most active member) were protracted from 1876 to 1895, and resulted in the publication of fifty royal quarto volumes, with plates, maps, sections, etc., the work of seventy-six authors, every shilling of the expenditure on which (some 50,000 pounds) was passed under the authority of the Committee of Publication.