It is difficult to realise how any reasonable man could teach such a farrago of nonsense when he must have heard Harvey’s perfectly simple and clear demonstration of the structure and uses of the heart. Harvey was lecturing on Tuesdays, Wednesdays, and Thursdays; Reid only lectured on Tuesdays, and Harvey had especially set himself to controvert the very errors that Reid was promulgating. But Reid was perfectly impenitent, for his Manual was reprinted in 1637, in 1638; and after his death it appeared again in 1642, 1650, 1653, and 1658, yet there is no alteration in his text. He was not even sure of the broad features of the anatomy of the heart, for he writes: “The first vessel in the chest is the vena cava or magna. The second vessel in the breast is vena arterialis. It is a vein from its office, for it carrieth natural blood to the lungs by the right side of the windpipe. It is called an artery because the coat of it is double, not single. It doth spring from the upper part of the right ventricle of the heart, and is implanted into the substance of the lungs by the right side of the windpipe.”
It seems obvious that this is a perverted description of the right auricle, and that Reid had no idea of the pulmonary artery as a distinct structure.
“The third vessel is arteria venalis. It is called an artery because it carrieth arterial blood, but a vein because it hath a single coat as a vein. It ariseth from the upper part of the left ventricle of the heart, and is implanted into the substance of the lungs by the left side of the windpipe.”
This in like manner appears to be the left auricle and the pulmonary veins.
“The vena arterialis hath three valves called sigmoides from the figure of the great sigma, which answereth the Latin S, the figure is this, C. They look from within outwards, to let out the blood but to hinder the return of the same.
“The arteria venalis hath two valves called mitrales, because they are like a bishop’s mitre. They look from without inward to let in blood carried from the vena arterialis. They are bigger than those of vena cava and have longer filaments and to strengthen them many fleshy snippets are joined together.
“It hath two valves only that the fuliginous vapours might the more readily be discharged.”
Reid, like all his contemporaries, had a glimmering of the lesser circulation, for he says: “First the blood is carried by vena arterialis and from hence to arteria venalis by sundry anastomoses, and from hence to the left ventricle of the heart. Where being made spirituous it is sent by the aorta to impart life to the whole body.
“One thing is to be noted that no air in its proper substance is carried to the heart; for the blood contained in these two vessels is sufficiently cooled by the bronchia passing between them.... One thing is to be noted, that in arteria venosa a little below the valves there is found a little valve ever open. It being removed, there appeareth a hole by the which the blood passeth freely from the vena cava to it and returneth by reason of this anastomosis that the blood in the veins may be animate.” This is a description of the foramen ovale and its use.