Chap. 21.] 
ACCOUNT or THE WOELD. 
53 
half a tone, and thence a tone and a half to the zodiac. 
Hence there are seven tones, which he terms the diapason 
harmony^, meaning the whole compass of the notes. In 
this, Saturn is said to move in the Doric time, Jupiter in the 
Phrygian^, and so forth of the rest ; but this is a refinement 
rather amusing than useful. 
CHAP. 21. (23.) — or THE DIMENSIONS OE THE WORLD. 
The stadium is equal to 125 of our Eoman paces, or 625 feet^. 
Posidonius"^ supposes that there is a space of not less than 
40 stadia around the earth, whence mists ^, winds and clouds^ 
proceed ; beyond this he supposes that the air is pure and 
liquid, consisting of uninterrupted light ; from the clouded 
region to the moon there ^.s a space of 2,000,000 of stadia, 
^ " AicL Traffuv, omnibus tonis contextam harmoniam." Hardouin in 
Lemaire, ii. 287. 
2 These appellatiorxS appear to have originated from different nations 
haviQg assumed diffarent notes as the foundation or commencement of 
their musical scale. The Abbe Barthelemi informs us, that " the Dorians 
executed the same air a tone lower than the Phrygians, and the latter a 
tone still higher than the Lydians ; hence the denomination of the Dorian, 
Phrygian, and Lydian modes." It appears to have been a general prac- 
tice to employ the lowest modes for the slowest airs ; Anacharsis's Travels, 
iii. 73, 74 
3 Hence the passus will be equal to 5 Roman feet. If we estimate 
the Roman foot at 11*6496 EngUsh inches, we shall have the miliar e of 
8 stadia equal to 1618 English yards, or 142 yards less than an EngHsh 
statute mile. See Adam's Roman Antiquities, p. 503 ; also the articles 
Mihare and Pes in Smith's Dictionary of G-reek and Roman Antiquities ; 
and for the varieties of the stadium, as employed at different periods and 
in different countries, see the article Stadium. The stadium wliich He- 
rodotus employed in measurements of Babylon has been supposed to 
consist of 490 Enghsh feet, while that of Xenophon and Strabo has been 
estimated at 505 ; see Ed. Rev. xlvui. 190. The Abbe Barthelemi sup- 
poses the stadium to be equal to 604 Enghsh feet ; Anach. Travels, vii. 284. 
^ There appears to have been two individuals of this name, who have 
been confounded with each other ; the one referred to by Pliny was an 
astronomer of Alexandria, who flourished about 260 years B.C. ; the other 
was a native of Apamea, a stoic philosopher, who lived about two cen- 
turies later ; see Aikin's Biog. in loco j also Hardouin's Index Auctorum, 
Lemaire, i. 209. 
^ The terms in the original are respectively nulila and rmbes. The 
lexicographers and grammarians do not appear to have accurately dis- 
criminated between these two words. 
