VITRUVIUS. 
arms, which are held by these cords, are both equally strained, they give the stroke 
properly; but if the cords are not in unison, the projectiles will vary, from their intended 
direction: so also the brasen vases in the little cells under the seats of the theatres, are disposed 
by mathematical rules, and the distinctions of their tones, which the Greeks call Echeid, are 
regulated by mufical concord and proportion, divided in the compass of diatessaron, diapente 
and diapason. So that the found of the voice from the stage, striking the correspondent vase 
resounds, and becomes stronger, clearer, and more melodious, in the hearing of the audience, 
neither can the hydraulic organs, and other similar machines, be constructed without the 
knowledge of music. 
THE study of physic is necessary, to be able to understand the nature of elimates, which 
the Grecks call Climata, and whether the air and water of places are wholesome or noxious 
for without good air and water no habitation can be healthy. 
Ir is requilite to have a knowledge of the laws, which are necessary for the regulation of 
the walls of public buildings. The gutters of the eaves, the fhores, lights, water channels. 
and lo forth, with which an architect should be well acquainted, in order that he may be 
careful at the beginning of the building, not to leave the father of the family involved in 
controversies after the work is finished; and that the conditions be written with caution and 
equity, both with regard to the employer and the artificer; for when the conditions are 
juitly described, both parties will remain free from altercation. By astronomy, is known 
the fituation of the east, west, south, and north, the motions of the heavens, the equinoctial 
(4*) The musical intervals, called the fourth, fifth, and 
mind, are the same; and the only difference between this 
octave. 
and the case of the musical tones is, that the sensation of the 
(5*) According to Tacitus and Suetonius, these organs 
proportions are conveyed to the perceiver by another con- 
were first known at Rome in the reign of Nero. See the 
ductor, (i. e.) another sense? It may not therefore be wholly 
Observations on the Life of Vitruvius, prefixed. 
without reason to suppose, that the same proportions wil 
(6*) Galiani, in his notes on this passage, imputes the 
have the same effect on either sense, the eye, as well as the 
degeneracy of modern architecture, to the modern architects 
ear; in figures, as well as in sounds and colours. 
(in general) being so ignorant of music; and observes how 
It may be observed, that the musical concords are most 
greatly the ancients attended to it in proportioning their 
plealing and harmonious comparatively, as their proportions 
buildings, as may be inferred from the remains of theit 
are the simplest, composed of the lowest numbers, and 
works; instancing in particular the sepulchre of the servants 
ealiest to be distinguished; as, for example, the octave, 
of Augustus, as published by Bianchini, who shews how 
which is, as one is to two, is a more perfect concord than 
perfectly its proportions agree with those of music. 
the fifth, which is as two to three; and that last is more 
Palladio, Alberti, and many others who have written on 
perfect than the fourth, which is, as three to four, &c. 
architecture, agree in the same opinion, and prescribe the ap¬ 
This observation then may serve as a hint to induce us (in 
plication of the musical proportions to works of architecture. 
cale of using the musical proportions in architecture, or in 
There is great reason to believe, that the same proportions 
any regular objects) to prefer the simplest that will serve the 
which are so pleasing to the ear, will allo please the eye. 
purpose. See Note 6, Chap. I. Book II. 
when applied to visible objects. For nature acts by the 
(7*) Galiani has observed, that the word communis should 
caliest and simplest means, and never varies the cause to 
be understood to signify exterior, and offers as proofs the 
produce the same effect, when the, same cause will answe. 
places, where the same word is again mentioned; viz. at 
the end. In colours, nature uses the same cause, and the 
Chapter VIII. Book II. and Chapter IX. Book VI. I how¬ 
lame effect arises; their harmony consisting in the same 
ever cannot help understanding it differently, even in those 
propoitions as prevail in musical tones; why not therefore. 
very places he quotes, and believe that the word communis 
in figures, in which case, the perceiver, the proportions 
is intended to signify common, or public. See the Notes 
perceived, and the senfe conveying thole proportionstothe a thode places.