Natural philosopher and inventor, Stephen Hales (1677-1761), undertook a lengthy series of experiments on animals described in Haemastaticks (1733) which led to the first direct measurement of blood pressure. Hales retained his interest in health and disease throughout his life, and this prompted what he regarded as his most important work: the invention of ventilation systems for use in ships or prisons. Hales was the 'perpetual curate' of Teddington, Middlesex, and he combined a mechanistic, quantitative approach to his experimental work with a need and, as he saw it, a duty to discover and wonder at the wisdom and goodness of God by studying His creation.