In the period covered by this volume, Tyndall completed his degree, published his first scientific papers, became a regular participant in the British Association meetings, established friendships with leading men of science in Berlin and London, and was elected Fellow of the Royal Society. As the volume ends, he was preparing his first lecture to the Royal Institution of Great Britain, the catalyst for a profound transition in his life. The letters offer a behind-the-scenes view of nineteenth-century publishing processes, the practices and challenges of diamagnetic research, the application procedures for university positions, the use of patronage in establishing a scientific career, and the often anxious and weary-worn personality of Tyndall, the ambitious protagonist.