DISCOVERY 



133 



contain blood because after death arteries are found to 

 be empty. By vivisectional methods Galen made the 

 discovery that the arteries contain blood during life. 

 According to him the veins contained " crude " blood, 

 the arteries pure or spirituous blood, that is, blood 

 mixed with vital spirits. The Galenical doctrine of 

 spirits, on which learned Europe subsisted for a millen- 

 nium, was somewhat complicated as it recognised no 

 less than three different kinds related somewhat in 

 the following manner. The food in the intestine was 

 supposed to be absorbed into the liver, where it was 

 elaborated so as to be possesses of " natural " spirits. 

 This crude blood then passed to the right side of the 

 heart, into which all the veins of the body opened. 

 This blood, still crude, was supposed to nourish the body 

 by passing up and down the veins as by the ebb and 

 flow of a tide. Its " natural spirits " in modern 

 terminology would be equivalent to " powers of 

 nourishing." Most of this crude blood was supposed 

 to percolate through invisible pores in the septum or 

 partition that divides the right from the left ventricle 

 of the heart, only a little of it going round by the 

 pulmonary arter\' to nourish the lungs. In the left 

 ventricle the blood was supposed to be mixed with air 

 inhaled in the act of breathing. Aristotle taught that 

 the inspired air was needed to cool the " innate heat " 

 of the heart ; Galen adopted this view and added an- 

 other result of the mixing of blood and air, namely, 

 the elaboration of " vital spirits." The great arterial 

 vessel of the body, the aorta, arises from the left 

 ventricle, so that blood plus vital spirits passed by the 

 arteries to the tissues and organs to confer on them the 

 powers of performing their specific functions. The vital 

 spirits, therefore, promoted functional activity of the 

 tissues. Finally, said Galen, blood plus vital spirits is 

 carried to the brain — an organ which Aristotle declared 

 was cold and bloodless — and there becomes the seat 

 of the production of a third order of spirit — the 

 " animal." This production of animal spirits was 

 supposed to go on in the ventricles or cavities of the 

 brain. These animal spirits, which as a term survive 

 only in colloquial English, were to Galen what nerve- 

 impulses are to us : but they were a great deal more, 

 for they were the very instrument of the soul itself. 

 The word " animal " does not in this connection mean 

 " belonging to a beast " ; it means pertaining to the 

 soul or aniina, the Latin equivalent for the Greek 

 psyche, the life or soul. The full Latin expression is 

 spiritus animalis. 



The animal spirits of Galen are in modern language 

 equivalent to consciousness generally, and to motor 

 and sensory innervations as well. Such is a simplified 

 account of the doctrine of spirits which was the ortho- 

 dox medical teaching as late as during the lifetime of 

 Shakespeare. It persisted in common parlance until 



long afterwards, for in the leign of Oueen Anne (1708) 

 the Daily Courant advertised a perfume as efficacious 

 because " it increases all the spirits, natural, vital and 

 animal," which is quite in the Galenical order. 



Let us now examine the passages in Shakespeare's 

 writings in which mention is made in some sort or other 

 of blood, blood-vessels, or heart. 



In Love's Labour's Lost (Act IV, Sc. 3) we have the 

 expression: "The nimble spirits in the arteries," a 

 direct echo of the Aristotelean-Galenical teaching. 



The veins are mentioned much more frequently. In 

 King John (Act III, Sc. 3) we find the expression 

 " blood . . . runs tickling up and down the veins." 

 The interest in this is, of course, the phrase " up and 

 down," which is precisely what was taught as regards 

 blood in veins before the unidirectional flow of blood 

 was demonstrated by Harvey. The pre-Harveian 

 notion of a tide, that is, an up and a down, a to and 

 fro movement in the veins is exactly reproduced in this 

 passage. In the same play we find the line 



" Whiles warm life plays in that infant's veins " — • 



and are at once reminded of the exceedingly old belief 

 that the life was pre-eminently in the blood. Not only 

 do we have in the Hebrew Scriptures the phrase, " for 

 the blood is the life," but also find the same idea in the 

 Hippocratic writings. The Hippocratic writer based 

 his belief on the familiar observation that, when the 

 blood has run out of the body of a slaughtered animal, 

 the animal dies. 



Once more in the same play we have this idea quite 

 distinctly put (King John, Act V, Sc. 7) ; " The life 

 of all his blood is touched corruptibly." 



Possibly the best-known passage in which the move- 

 ment of the blood is alluded to is in Coriolanus (Act I, 

 Sc. i), where Menenius .\grippa, a friend of Coriolanus, 

 speaking of the belly, says : 



■■ True it is . . . that I receive the general food at first 

 Which vou do live upon, and fit it is. 

 Because I am the storehouse and the shop 

 Of the whole body : But if you do remember, 

 I send it through the rivers of your blood 

 Even to the court, the heart — to the seat o' the brain. 

 And through the cranks and offices of man, 

 The strongest nerves and small inferior veins 

 From me receive that natural competency 

 Whereby they live." 



Now, while it is quite absurd to see in this not only 

 modern physiology but a prophetic vision of Harvey's 

 discovery, the passage is not wanting in biological 

 interest. The general idea of the abdominal viscera 

 receiving food and working it up into the blood des- 

 tined for the nourishment of the whole body, including 

 the nerves and brain, is involved in this passage and so 

 far is physiologically correct. But undoubtedly it is 



