IMA´US
IMA´US the great mountain chain, which, according to the ancients, divided Northern Asia into “Scythia intra Imaum” and “Scythia extra Imaum.” This word (τὸ Ἴμαον ὄρος, Strab. xv. p.689; Ptol. 6.13.1; τὸ Ἰμαῖον ὄρος, Strab. ii. p.129; ὁ Ἴμαος, Agathem. 2.9: although all the MSS. of Strabo (xi. p.516) have Isamus (Ἴσαμος) in the passage describing the expedition of the Graeco-Bactrian king Menander, yet there can be no doubt but that the text is corrupt, and the word Imaus should be substituted), connected with the Sanscrit himavat, “snowy” (comp. Plin. Nat. 6.17; Bohlen, das Alte Indien, vol. i. p. 11; Lassen, Ind. Alt. vol. i. p. 17), is one of those many significative expressions which have been used for mountain masses upon every zone of the earth's surface (for instance, Mont Blanc, in Savoy, Sierras [p. 2.41]Nevada, in Granada and California), and survives in the modern Himálaya.From very early times the Greeks were aware of a great line of mountains running throughout Central Asia, nearly E. and W., between the 36th and 37th degrees of latitude, and which was known by the name of the diaphragm of Dicaearchus, or the parallel of Rhodes.
The Macedonian expeditions of Alexander and Seleucus Nicator opened up Asia as far as the sources of the Ganges, but not farther. But the knowledge which the Greeks thus obtained of Asia was much enlarged by intercourse with other Eastern nations. The indications given by Strabo and Ptolemy (I.c.), when compared with the orographic configuration of the Asiatic continent, recognise in a very remarkable manner the principal features of the mountain chain of Central Asia, which extends from the Chinese province of Hou-pé, S. of the gulf of Petcheli, along the line of the Kuen-lün (not, as has generally been supposed, the Himálaya), continuing from the Hindú--Kúsh along the S. shores of the Caspian through Mázanderán, and rising in the crater-shaped summit of Damávend, through the pass of Elburz and Ghilan, until it terminates in the Taurus in the SW. corner of Asia Minor. It is true that there is a break between Taurus and the W. continuation of the Hindú--Kúsh, but the cold “plateaux” of Azerbijan and Kurdistán, and the isolated summit of Ararat, might easily give rise to the supposed continuity both of Taurus and Anti-Taurus from Karamania and Argaeus up to the high chain of Elburz, which separates the damp, wooded, and unhealthy plains of Mázanderán from the arid “plateaux” of Irak and Khorasan.
The name of Imaus was, as has been seen, in the first instance, applied by the Greek geographers to the Hindú--Kúsh and to the chain parallel to the equator to which the name of Himálaya is usually given in the present day. Gradually the name was transferred to the colossal intersection running N. and S.,--the meridian axis of Central Asia, or the Bolor range. The division of Asia into “intra et extra Imaum” was unknown to Strabo and Pliny, though the latter describes the knot of mountains formed by the intersections of the Himárlaya, the Hindú--Kúsh, and Bolor, by the expression “quorum (Montes Emodi) promontorium Imaus vocatur” (6.17). The Bolor chain has been for ages, with one or two exceptions, the boundary between the empires of China and Turlkestan; but the ethnographical distinction between “Scythia intra et extra Imaum” was probably suggested by the division of India into “intra et extra Gangem,” and of the whole continent into “intra et extra Taurum.” In Ptolemy, or rather in the maps appended to all the editions, and attributed to Agathodaemon, the meridian chain of Imaus is prolonged up to the most northerly plains of the Irtych and Obi. The positive notions of the ancients upon the route of commerce from the Euphrates to the Seres, forbid the opinion, that the idea of an Imaus running from N. to S., and N. of the Himálaya, dividing Upper Asia into two equal parts, was a mere geographic dream. The expressions of Ptolemy are so precise, that there can be little doubt but that he was aware of the existence of the Bolor range. In the special description of Central Asia, he speaks twice of Imaus running from S. to N., and, indeed, clearly calls it a meridian chain ῾καρὰ μεσημβρινήν πως γραμμήν, Ptol. 6.14.1: comp. 6.13.1), and places at the foot of Imaus the BYLTAE (Βῦλται, 6.13.3), in the country of Little Thibet, which still bears the in-digenous name of Baltistan. At the sources of the Indus are the DARADRAE (8.1.42), the Dardars or Derders mentioned in the poem of the Mahábhárata and in the fragments of Megasthenesy through whom the Greeks received accounts of the region of auriferous sand, and who occupied the S. slopes of the Indian Caucasus, a little to the W. of Kaschmir. It is to be remarked that Ptolemy does not attach Imaus to the COMEDORUM MONTES (Koundouz), but places the Imaus too far to the E., 8° further than the meridian of the principal source of the Ganges (Gungótrí). The cause of this mistake, in placing Imaus so far further towards the E. than the Bolor range, no doubt arose from the data upon which Ptolemy came to his conclusion being selected from two different sources. The Greeks first became acquainted with the Comedorum Montes when they passed the Indian Caucasus between Cabul and Balkh, and advanced over the “plateau” of Bamian along the W. slopes of Bolor, where Alexander found, in the tribe of the Sibae, the descendants of Heracles (Strab. xvi. p.688), just as Marco Polo and Burnes (Travels in Bokhara, vol. ii. p. 214) met with people who boasted that they had sprung from the Macedonian conquerors, The N. of Bolor was known from the route of the traffic of the Seres, as described by Marinus of Tyre and Ptolemy (1.12). The combination of notions obtained from such different sources was imperfectly made, and hence the error in longitude.
These obscure orographical relations have been illustrated by Humboldt upon the most logical principles, and the result of many apparently contradictory accounts is so presented as to form one connected whole. (Asie Centrale, vol. i. pp. 100--164, vol. ii. pp. 365--440.)
The Bolor range is one link of a long series of elevated ranges running, as it were, from S. to N., which, with axes parallel to each other, but alternating in their localities, extend from Cape Comorin to the Icy Sea, between the 64th and 75th degrees of longitude, keeping a mean direction of SSE. and NNW. Lassen (lndische Alterthemskunde) coincides with the results obtained by Humboldt.
[E.B.J]