 On 15 January 1888 Baker was appointed assistant curator to Joseph Henry Maiden at the Technological Museum, and in 1901 succeeded Maiden as curator and economic botanist.In 1902 Baker published an important work, "A Research on the Eucalypts especially in regard to their essential oils", prepared in collaboration with Henry George Smith, second and enlarged edition, 1920.Baker published a small book, "Building and Ornamental Stones of New South Wales" (1908), and, again in collaboration with Henry Smith, another valuable piece of research, "A Research on the Pines of Australia" (1910).