 Priestley attempted to continue his scientific investigations in America with the support of the American Philosophical Association. However, he was hampered by lack of news from Europe; unaware of the latest scientific developments, Priestley was no longer on the forefront of discovery. Although the majority of his publications focused on defending the outmoded phlogiston theory against the "new chemistry", he also did some original work on spontaneous generation and dreams. As Robert Schofield, Priestley's major modern biographer, explains:
