NavList:

I'd posted previously a question as to whether anyone actually used length of day to determine latitude.   I actually stumbled upon the work of a medieval Arab geographer, Yaqut, who used the length of day as a method of marking the zones of the 7 "climes" of the "occupied world".   I think both the idea of climes and occupied world (oecumene) is Greek in origin, but I was unaware of a classification scheme based on the length of day.  

In this case, he uses the length of day at the summer solstice.   Knowing this information, one can figure out the latitudes of the boundaries of his climes.     He also uses the length of a shadow stick at the equinox at meridian passage, but there are too many inconsistencies in his account.   Length of day seems better.

Does anyone know who a medieval Arab would measure the length of day?   Sun-dial simply?   Klepsidra? Hour glass?

Clime listing from Wadie Jwaideh’s translation of Yaqut’s Mu-Jam Al-Buldan

 

First clime

 

Longest day = 12 ½ hours at southern end (12 ¾ from al-Biruni, Tafhim)

13 hours = middle

13 ¼ = northern end

 

12 ½ = 9^o N, 12 ¾ = 12^o N

13 hours = 17^o N

13 ¼ = 21^o N

 

Locations cited:  

 

Southern China,  Ceylon/Sarandib/Cerendin, seacoast of “Sind” , Yaman, Sea of Qulzum (Alcuzum in Marseilles tables), Abyssini, Nile, ends in the Sea of Maghrib.   

 

Island of al-Kark, southern India, Sanaa, Aden, Hadramawt, Najran, Jurash, Jayshan, Sa’dah, Saba, Zufar, Mahrah, Uman.   Lands of the Maghrib:  Tabalah, Jarmi, capital city of Abyssinia, Dumqalah, capital city of Nubia, southern Berbers, Ghanah (country of the Sudan of the Maghrib) and then the Green Sea.   Green Sea = surrounding ocean

 

Note that Cerendin is listed as 3^o N in Marseilles tables.

 

It is the clime of Saturn, agreed by the Persians and Byzantines.   Capricorn and Aquaris are its signs. 

 

Second clime

 

 

13 ¼   hours at southern end 21^o N

13 ½   hours = middle  24^o N

13 ¾    = northern end 28^o N

 

Passes:   China, India (northern parts – Sind, Qamrun, Kanuj), confluence of the Sea of Basrah and the Green Sea, the lands of Najd, Tihamah and Al-Bahrayn, the Sea of Qulzum, the Nile  and the lands of the Maghrib.

 

Cities:   al-Mansurah, the lands of the Tatars, Daybul.    Yathrib, furthest southern section is a bit beyond Mecca,  Ansina, Aswan.

 

It is the clime of Jupiter according to the Persians, according to the Byzantines, it is the clime of the Sun.   Sagittarius and Pisces are its signs. 

 

Third clime

 

13 ¾    hours at southern end 28^o N

14   hours = middle  31^o N

14 ¼     = northern end 34^o N

 

Kabul, Alexandria, Baghdad, Qandahar, Tyre, Beruit, Kabul, Damascus, Tyre, Jerusalem, Gaza, Qulzum, Damietta, Tangier

 

Clime of Mercury, Aries and Scorpio

 

Fourth clime

 

14 ¼   hours at southern end 34^o N

14 ½    hours = middle  37^o N

14 ¾    = northern end 39^o N

 

Cyprus, Rhodes, Sicily, Straits of Gibraltar, Aleppo, Antioch, Adana, Samarra, Persepolis

 

Clime of Jupiter, Leo

 

Fifth clime

 

14 ¾   hours at southern end 39^o N

15     hours = middle  42^o N

15 ¼    = northern end 44^o N

 

Farghanah, Samarqand, Bukhara, Sea of the Khazars, Armenia, Rumiyah al-Kubra (Rome)

 

Clime of Venus, Taurus and Libra

 

Sixth clime

 

15 ¼   hours at southern end 44^o N

15 ½   hours = middle  46^o N

15 ¾    = northern end 47^o N

 

Constantinople, Heraclea

 

Clime of Mercury (Persians), Moon (Byzantines), Gemini and Virgo

 

Seventh clime

 

15 ¾   hours at southern end 47^o N

16   hours = middle  49^o N

16 ¼     = northern end 51^o N

 

Rus, Varangians, Slavs, Suwar

 

“The end of this clime marks the end of the oecumene, beyond which no one is to be found save a people of no consequence.   In their impoverished state and lack of refinement, they are more like wild beasts than men. “

 

Clim of the Moon (Persians), Mars (Byzantines), Cancer.

 

 

 

 

 

 

 

--
NavList message boards: www.fer3.com/arc
Or post by email to: NavList@fer3.com
To , email NavList+@fer3.com