William Cullen (1710–1790) of Edinburgh, Scotland had engaged in a flourishing mail order practice. In his early years of practice between 1764 and 1774, Cullen wrote approximately 20 consultation letters per year. This number jumped markedly to almost 200 a year from 1774 till his death in 1790. He had used an amanuensis and an early version of a copying machine to make it quicker and easier for him to respond. If he did not know the condition well, he cautiously avoided making a diagnosis. For the acutely ill, he preferred hospital admission and personal care. Cullen had recognized long ago the limitations of care.