548 Account of the Mohit, a Nautical [Nov. 



shown from numerous proofs. If you sail under a cloudy sky, with a strong 

 wind, and a cloud approaches the ship from one side, so that the cold of the 

 cloud is sensible, the first wind ceases, and with its ceasing, the cold ceases 

 also ; further, winds blowing from the land set in at night, and those 

 blowing during the day come from the sea, and cease when night approaches ; 

 the cause of which is, that at night the earth grows cool, and the sea remains 

 warm, the contrary of which is the case during day-time, because, by the 

 reverberation of the rays of the sun, mountains and deserts are heated during 

 the day. Another proof is, that the coldness of sandy deserts is stronger 

 than that of a mountainous country, and ground" watered by rain is colder 

 than ground which is not drenched by rain. Another proof is, that a cloud, 

 particularly when in motion, pi-oduces wind, arising from the cold which is 

 hoarded up in the cloud. The principal winds are four, according to the 

 Arabs, the Northern, Southern, Eastern, and Western ; those between 

 them are called sidewinds (Nokeba) ; but the pilots call them by names 

 taken from the rising and setting of certain stars, and assign them certain 

 limits, within which they begin or attain their greatest strength, and cease. 

 These winds, limited by space and time, are called Mausim {Monsoon) ; 

 viz. seasons. 



The following Arabic verses give the names of the four cardinal winds: 



Saba (the East) blows from the rising of the sun. From the Polar Star 

 comes the North wind, called Shemeul ; and from Canopus, the South wind, 

 called Janub ; opposite to the East blows the West wind, Dobur. 



Section 2. Of the different sorts of monsoons, and the time they blow in. 



Be it known, that the ancient masters of navigation have fixed the time 

 of the monsoon, that is to say, the time of voyages at sea, according the 

 year of Yazdajird, and that the pilots of recent time follow their steps ; 

 but as there is in every true solar, that is to say JaldMan, year, near the 

 fourth of a degree more, every four years, a day is intercalated, so that 

 this day is deficient in the Ya.zdajirdian year. The late master Suleima'n 

 Ben Ahmad wrote his book Omdat (the column) in the year of the Hijra 

 917 (1511), and fixed then the time of the monsoons according to that year, 

 since which, up to that of this translation, 961 (1753), more than forty years 

 have elapsed, so that the time fixed by him for the monsoon, falls now short 

 hy ten days. For example, the monsoon which set then in on the 120th day 

 of the Yazdajirdian year, sets in now on the 130th, and that which was fixed 

 then on the 160th, falls now on the 170th. The rest must be calculated in the 

 same way, in order to avoid error and confusion ; but even the intercalation 

 of a day every fourth or fifth year is not free of error ; it is, therefore, the 

 most expedient to calculate according to the zodiacal year*, that is to 

 say, the JaldMan year, which requires no intercalary days. The mon- 

 soon of each country is limited by its fixed time. Remark further, 

 that wherever the word fi (about) is added, it is to be understood, 

 that the monsoon sets in about the time stated; for example, if it is 

 said about the tenth of the year, means that it does not exactly set in on 



* — « y i &X*» the year of the constellations. 



XL?-'' 



