( 38 ) 



direct line. . . . The part of the blood which reaches the brain serves not only to 

 nourish it and maintain its substance, but its chief use is to produce there a very lively 

 and pure flame -which is called the animal spirits. The arteries which bring the blood from 

 the heart, after dividing into an infinite number of small branches and having formed 

 those delicate tissues which cover as with a carpet the floor of the ventricles of the brain, 

 are gathered round a certain little gland which is placed about the middle of the substance 

 of the brain just at the entrance to its ventricles, and in this situation these arteries have 

 a large number of minute pores or holes through which the more subtle particles of the 

 blood can flow into this gland, but which are so narrow as that they prevent the passage 

 through them of grosser particles. [He gives a remarkable figure of the straight course 

 of the arteries to the gland.] . . . The arteries do not end there, but, being gathered 

 together there once again, they ascend straight upward and join the great vessel which is 

 lite a Euripus and which bathes the outer surface of the brain." (L'Homme p. 344.) 



The pineal gland is thus the primary reservoir or bureau, the 

 ventricles secondary reservoirs, of the animal spirits which flow from 

 the brain along the tubular nerves, thus causing movements, the 

 spirits themselves being generated from the innate heat of the heart. 

 The pineal gland is also the seat of the rational soul. It is the " seat 

 of imagination and of common sensation." 



FORMATION OF INVERTED IMAGE OF AN 

 EXTEBNAL OBJECT IN THE RETINA. 



FIGURE A SHOWING HOW THE IMPRESSION OF THE IMAGE OF 



AN EXTERNAL OBJECT ON THE RETINA BEACHED 



THE PINEAL GLAND. 



Passing over his many disputations and controversies, we come 

 to the invitation in 1648 of that remarkable woman, Queen Christina, 

 daughter of Gustavus Adolphus, " the pious and valiant King of 

 Sweden," who was killed at Lutzen in 1632 — we have already 

 referred to her residence in Rome and her relations to Borelli — to 

 him to reside in Stockholm that she might learn his philosophy direct 

 from himself. This remarkable lady required his attendance at five 

 a.m.— a very different hour from that usually selected by Descartes for 

 active study, who usually lay in bed the better part of the forenoon 

 meditating and writing. He died of pneumonia on February 11th, 

 1650, set. 54. 



A 



