The time and opportunity for fulfilling this pledge soon came, for in the year 1823 the Negroes in Jamaica commenced their agitation for obtaining equal privileges with their white brethren. It does not appear that Hill attached himself openly to any of the societies that were formed for the purpose of carrying on this agitation. But he freely gave them the benefit of his abilities, helping the whole movement with his advice and with his pen.[2]
In the year 1826 Hill visited Cuba, the United States and Canada, and then went on to England, landing there in September. In 1827 he was deputed by the organization in Jamaica to use his efforts in England to secure the assistance of the leading members of the Anti-Slavery party. During his stay there he was on terms of close intimacy with Wilberforce, Buxton, Clarkson, Babington, Lushington and Zachary Macaulay,[3] all members of the Anti-Slavery Society, as well as Pringle and other men eminent for their philanthropy and talents and noted for the deep interest they took in all that related to the elevation and welfare of the Negroes of the British West Indian colonies. The petition from the people of color of this island to the House of Commons for the removal of their civil disabilities, was entrusted to Hill, who upon the occasion of presenting it was permitted "within the bar" of the House. On that occasion Canning delivered his last speech a splendid effort in favor of the petitioners. Hill remained several years in England and contributed largely by his pen and his speeches to enlighten the public mind of England as to the real character of West Indian slavery. But the remittances from the "people of color" in Jamaica, never very large, soon became few and far between. So Hill, always independent in every way, even in his friendships and political alliances, maintained himself and his sister, Jane, almost entirely by his contributions, literary and scientific, to several popular newspapers and periodicals.[4]
After a residence of several years in England, Hill was sent by the Anti-Slavery Society on a visit to San Domingo, chiefly for the purpose of ascertaining by personal observation and inquiry what was the actual social and political condition of the people of that island.[5] But his commission had a more extensive object than that attached to it, which, however, directed him to obtain besides all the information he possibly could concerning the natural resources of every part of the country through which he was to travel. San Domingo was then under the wise and able rule of President Boyer, the whole island forming one undivided republic, enjoying internal tranquillity, and being in a comparatively flourishing condition. On his way from England to Port-au-Prince, where he arrived on the sixteenth of June, 1830, Hill visited France staying there a few months. He spent nearly two years in San Domingo travelling incessantly and making notes about everything. He has left more than one sketch-book full of sketches showing a knowledge of perspective, a keen eye for the picturesque and a true artist's feeling. He sailed from San Domingo for England on the third of May, 1832, and then for Jamaica a few months after, never again to quit his native country. In that year he was made justice of the peace for Trelawny.