Galen: On the Natural Faculties by Galen

Chapter XIV

57 words  |  Chapter 44

The superficial arteries, when they dilate, draw in air from the atmosphere, and the deeper ones a fine, vaporous blood from the veins and heart. Lighter matter such as air will always be drawn in preference to heavier; this is why the arteries in the food-canal draw in practically none of the nutrient matter contained in it.