As a boy he had delighted in the history of inventions and devices, and the army had given him hands-on experience; his doctoral thesis which was on 17th-century ballistics was published as a book in 1952.
Hall was unusual in coming to the discipline from history, not science, and his background would yield fresh and different perspectives in this new emerging field.
Hall won him round, and they were to co-operate in editing the five-volume History of Technology published by Oxford University Press in 1954–1958.
In 1948 Hall was appointed as the first curator of the Whipple Museum of the History of Science, in Cambridge, and in 1950 began lecturing in the subject.
[4] Between 1962 and 1986 the Halls edited, translated and published in 13 volumes the correspondence of Henry Oldenburg,[5] the secretary of the Royal Society in its early days, and founding editor of its journal, Philosophical Transactions, which grew out of his extensive international letter-writing.