Vitruvius also more than once implies his confidence in the art of astrology. In mapping out the ground-plan of his theater he advises inscribing four equilateral triangles within the circumference of a circle, “as the astrologers do in a figure of the twelve signs of the zodiac, when they are making computations from the musical harmony of the stars.”[863] I cannot make out that there is any astrological significance or magical virtue in this so far as the arrangement of the theater is concerned, but it shows that Vitruvius and his readers are familiar with the technique of astrology and the trigona of the signs. In another passage, comparing the physical characteristics and temperaments of northern and southern races, which astrologers generally interpreted as evidence of the influence of the constellations upon mankind, Vitruvius patriotically contends that the inhabitants of Italy, and especially the Romans, represent a happy medium between north and south, combining the greater courage of the northerners with the keener intellects of the southerners, just as the planet Jupiter is a golden mean between the extreme influences of Mars and Saturn. So the Romans are fitted for world rule, overcoming barbarian valor by their superior intelligence and the devices of the southerners by their valor.[864] In a third passage Vitruvius says more expressly of the art of astrology: “As for the branch of astronomy which concerns the influences of the twelve signs, the five stars, the sun, and the moon upon human life, we must leave all this to the calculations of the Chaldeans, to whom belongs the art of casting nativities, which enables them to declare the past and the future by means of calculations based on the stars. These discoveries have been transmitted by men of genius and great acuteness who sprang directly from the nations of the Chaldeans; first of all, by Berosus, who settled in the island state of Cos, and there opened a school. Afterwards Antipater pursued the subject; then there was Archinapolus, who also left rules for casting nativities, based not on the moment of birth but on that of conception.” After listing a number of natural philosophers and other astronomers and astrologers, Vitruvius concludes: “Their learning deserves the admiration of mankind; for they were so solicitous as even to be able to predict, long beforehand, with divining mind, the signs of the weather which was to follow in the future.”[865]
Divergence between theory and practice, learning and art.
Such a passage demonstrates plainly enough Vitruvius’ full confidence in the art of casting nativities and of weather prediction, but it has no integral connection with his practical architecture or even any necessary connection with the construction of a sun-dial, which is what he is actually driving at. But Vitruvius believed that an architect should not be a mere craftsman but broadly educated in history, medicine, and philosophy, geometry, music, and astronomy, in order to understand the origin and significance of details inherited from the art of the past, to assure a healthy building, proper acoustics, and the like. It is in an attempt to air his learning and in the theoretical portions of his work that he is prone to occult science. But the practical processes of architecture and military engineering are free from it.
Evils in contemporary learning.
The attitude of Vitruvius towards other architects of his own age, to past authorities, and to personal experimentation is of interest to note, and roughly parallels the attitude of Galen in the field of medicine. Like Galen he complains that the artist must plunge into the social life of the day in order to gain professional success and recognition.[866] “And since I observe that the unlearned rather than the learned are held in high favor, deeming it beneath me to struggle for honors with the unlearned, I will rather demonstrate the virtue of our science by this publication.”[867] He also objects to the self-assertion and advertising of themselves in which many architects of his time indulge.[868] He recognizes, however, that the state of affairs was much the same in time past, since he tells a story how the Macedonian architect, Dinocrates, forced himself upon the attention of Alexander the Great solely by his handsome and stately appearance,[869] and since he asserts that the most famous artists of the past owe their celebrity to their good fortune in working for great states or men, while other artists of equal merit are seldom heard of.[870] He also speaks of those who plagiarize the writings of others, especially of the men of the past.[871] But all this does not lead him to despair of art and learning; rather it confirms him in the conviction that they alone are really worth while, and he quotes several philosophers to that effect, including the saying of Theophrastus that “the learned man alone of all others is no stranger even in foreign lands ... but is a citizen in every city.”[872]
Authorities and inventions.
In contradistinction to the plagiarists Vitruvius expresses his deep gratitude to the men of the past who have written books, and gives lists of his authorities,[873] and declares that “the opinions of learned authors ... gain strength as time goes on.”[874] “Relying upon such authorities, we venture to produce new systems of instruction.”[875] Or, as he says in discussing the properties of waters, “Some of these things I have seen for myself, others I have found written in Greek books.”[876] But in describing sun-dials he frankly remarks, “I will state by whom the different classes and designs of dials have been invented. For I cannot invent new kinds myself at this late day, nor do I think that I ought to display the inventions of others as my own.”[877] He also gives an account of a number of notable miscellaneous discoveries and experiments by past mathematicians and physicists.[878] Also he sometimes repeats the instruction which he had received from his teachers. Like Pliny a little later he thinks that in some respects artistic standards have been lowered in his own time, notably in fresco-painting.[879] But also, like Galen, he once admits that there are still good men in his own profession besides himself, affirming that “our architects in the old days, and a good many even in our own times, have been as great as those of the Greeks.”[880] He describes a basilica which he himself had built at Fano.[881]
Machines and Ctesibius.
Vitruvius’s last book is devoted to machines and military engines. Here he makes a feeble effort to introduce the factor of astrological influence, asserting that “all machinery is derived from nature, and is founded on the teaching and instruction of the revolution of the firmament.”[882] Among the devices described is the pump of Ctesibius of Alexandria, the son of a barber.[883] He had already been mentioned in the preceding book[884] for the improvements which he introduced in water-clocks, especially regulating their flow according to the changing length of the hours of the day in summer and winter. Vitruvius also asserts that he constructed the first water organs, that he “discovered the natural pressure of the air and pneumatic principles, ... devised methods of raising water, automatic contrivances, and amusing things of many kinds, ... blackbirds singing by means of waterworks, and angobatae, and figures that drink and move, and other things that have been found to be pleasing to the eye and the ear.”[885] Vitruvius states that of these he has selected those that seemed most useful and necessary and that the reader may turn to Ctesibius’s own works for those which are merely amusing. Pliny more briefly mentions the invention of pneumatics and water organs by Ctesibius.[886]
Hero of Alexandria.