He also studied in the British Museum, and two years later became a student of the Royal Academy, where he gained silver medals for modelling from the antique, and in 1841 for the first time exhibited a "Bust of a Gentleman".
That year he sent a marble bust of "Hebe" to the Royal Academy, which was purchased by the Art Union of London and reproduced in bronze.
Although successful in this and other works, Gatley saw no prospect of earning an adequate income in England, and so went to Rome towards the end of 1852, where he took a studio on the Pincian Hill, and made the acquaintance of John Gibson, whose enthusiasm for Greek art he shared.
Soon after Gatley's settlement in Rome, Samuel Christie-Miller invited him to prepare designs for the sculptural decorations of a mausoleum to be erected to the memory of William Henry Miller at Craigentinny, his estate near Edinburgh.
Gatley produced a model of a large bas-relief representing "The Overthrow of Pharaoh in the Red Sea", which was highly praised by Gibson.
In the judgement of Robert Edmund Graves, Gatley's DNB biographer, "The two bas-reliefs are in strong contrast to each other, the idea of rejoicing being as powerfully given in the one work as is that of fear and impending destruction in the other".