Page:Popular Science Monthly Volume 2.djvu/701

Rh they are of too general an interest to be reserved for physiologists and physicians; they must enter into the wide domain of Science.

In the order of scientific facts a great discovery never remains isolated, but opens unknown horizons, and leads to useful applications, by the conquest of new principles. No one, nowadays, is ignorant that the labors of Ampère in electricity and magnetism created the telegraph. In Harvey's time, circulation was accepted, spite of protests by the faculty and the disciples of Galen; a genius like Descartes publishes it in his famous "Discourse on Method;" demonstration by experiment confirms the position of theory in every point; and the most important consequences immediately follow. They affect the knowledge of drugs and poisons, the anatomy of man, and the medical art that heals him. It was easily understood that medicinal and injurious substances will act more promptly if introduced directly into the vessels, and Fabricius, a doctor of Dantzic, infused purgative salts into the veins. Fracassati, a professor of anatomy at Pisa, injected alcohol, spirits of vitriol, oil of sulphur and of tartar. These experiments did not advance the healing art much, but they led to one important consequence, probably unlooked for by their authors: they were the commencement of a process which allows us to study the nature of poisons; and the history of poisoning afterward took a new direction.

To the physician and the anatomist the process of transfusion was directly and immediately useful. A century earlier, the illustrious Andreas Vesalius had created human anatomy; after the publication of Harvey's works, the arteries and veins were studied in preference. In the class-room where dissections are going on, it is out of the question to transfuse living blood; but, for the advantage of following the course and distribution of the vessels, it is useful to inject them with such colored matters as will solidify. The Dutch Frederic Ruysch is the leader in this advance. In the land of Rembrandt the art of harmonizing colors aims not merely to bring the human countenance to life again on canvas; the anatomist of Leyden so well understands the secret of injections that, by imparting color to the interior of the tissues, he will restore the semblance of life to inanimate bodies; when, near the end of his long career, Ruysch put to press in Amsterdam the remarkable book in which he describes the wonders of the anatomical museum of his native town, like an artist content with the perfection of his work, he exclaims, at the first page, "I have babies there that have been embalmed for twenty years; they are so rosy and fresh that you would say they are not dead, but asleep."

Ruysch's anatomical preparations, of which the secret is now lost, were contemporary with that marvellous experience, also founded on the discovery of Harvey—we mean transfusion of actual blood. About 1660 the notions in medicine of the ancients were strongly and