Now, it is well known, that from this position a vessel steering for the coast of Africa towards Cape Guardafui (the southern extremity of the Gulf of Aden), and thence to the Straits of Bab-el-Mandeb (the entrance of the Red Sea), would carry the wind a-beam, and could therefore make her passage to or from the Straits of Bab-el-Mandeb, and the given point to the southward of Ceylon, during the whole of the south-west monsoon.
As the north-east monsoon blows in an exactly opposite direction to the south-west monsoon, and is much more moderate, a sailing vessel could make good her course between the Red Sea and the same point south of Ceylon, equally well as in the south-west monsoon, and therefore during the whole year could effect this part of the passage with tolerable certainty.
Vessels proceeding to or from Bombay would have to arrange their passages to suit the monsoons. Sailing from England, or other places in Europe, so as to have the south-west monsoon in their favour; and sailing from Bombay for Europe so as to have the north-east monsoon in their favour.
It hence appears that the monsoons present no particular difficulties in the voyage between India, &c. and the entrance of the Red Sea, more than in the ordinary route by the Cape of Good Hope; but that, on the contrary, for ships trading with the eastern and most important parts of Hindostan, and to Ceylon, Malacca, Singapore, Java, China, &c. this part of the voyage would be made with more certainty than an equal distance in the Indian Ocean, of a voyage by the Cape of Good Hope route.
The Red Sea Passage.
The length of the Red Sea from the Straits of Bab-el-Mandeb to Suez is 1200 miles, its medium breadth about 150 miles, and its direction nearly N. N. W. and S. S. E.
Its coasts on either side are fringed with coral rocks, which render it dangerous in navigating it to approach near its shores.
In the southern part of it, say from the latitude of Jidda to Bab-el-Mandeb, being about one-half of its whole length, the southerly monsoon predominates nearly two-thirds of the year, commencing in October and ending in May or June. The northerly winds then set in, and continue about four months, say June, July, August, and September.
Outside the Red Sea, in the Gulf of Aden, the wind generally prevails from the eastward for six months, say, from October to May, and from the westward during the other part of the year.
In the northern part of the sea, from Jidda to Suez, but more particularly near to Suez, the prevailing winds for nine months of the year are northerly, and in the months of June, July, and August, it is very difficult for sailing vessels to beat up to Suez. In this part of the Red Sea southerly breezes are at all times but of short duration.