The 1653 English edition of De motu cordis, shown to be Harvey's vernacular original and revealing crucial aspects of his pre-circulation theory and its connection to the discovery of the circulation of the blood

From a comparative study of the first Latin edition of William Harvey's De motu cordis published in 1628, and the first English edition published in 1 653, it is argued that the latter is the printed copy of Harvey's original manuscript written in the vernacular. It will also be shown that Harvey's p re-circulation theory described the heart as an impulsor of blood for sever al years before his discovery of the circulation of the blood. The crucial aspect of his description was a new explanation of the cause of the arteria l pulse as felt at the extremities.