376 PHILOSOPHICAL TRANSACTIONS. [aNNO IGOQ, 



ships that are outward bound to the Straits keep near the coast of Portugal, 

 bat homeward bound they are many times forced to run far west to fetch a 

 westerly wind. Likewise ships bound to Barbadoes go by the Canaries, but 

 come home a great way to the north-west of the Azores. And the Virginia 

 ships are twice as long in going out as they are in coming home, and many 

 times longer : for they come home directly before the wind, but go out round 

 about as far as the tropic, or at least to 28 degrees latitude, for the benefit of 

 the north-east wind; and when that has carried them far west, they come back 

 to the northward again : and then, as the westerly wind hangs more or less 

 southerly, they have a good or bad passage. About 3 or 4 degrees northern 

 latitude the south-east wind begins to take place, between the equator and the 

 tropic of Capricorn. But the nearer you are to the coast of Africa, it is so 

 much more southerly ; and as you approach to the coast of Brasil, it inclines 

 more and more easterly. And there is not only a variation in the wind in re- 

 spect of longitude, but also in respect of latitude : for, near the equator, the 

 wind is more southerly than it is in the same meridian near the tropic of 

 Capricorn ; as for example, in the great bay of Guinea, which our seamen call 

 the Bight of Guinea, the wind is mostly south ; and inclines as much to the 

 west as to the east : but in the same meridian near the tropic of Capricorn, it is 

 constantly between south-east by east, and south-east by south. And on the 

 contrary, in that meridian which may be about 100 leagues to the eastward of 

 Brasil, near the equator, the wind is between south-east and east-south-east; 

 and in the same meridian the winds near the tropic are more variable, but most 

 part about north-east. 



In our latter voyage, after we came to 32 deg. south latitude (to which 

 place from the line we were much hecalmed) we had fair weather, and a con- 

 stant wind between WNW. and WSW. all along to the Cape; in that vast 

 space between Rio de la Plata and the Cape, the wind being all the year westerly. 

 But about the Cape, from the end or middle of September to the beginning of 

 April, the winds are variable as in England. The rest of the year they are 

 westerly, with intolerable storms. 



Considerations on the Variety of Slate, and a Computation of the 

 Charges of covering Houses with them. By Mr. Sam. Colepress. 

 iV" 50, p. 1009. 



Among the several materials for building, that for covering is not the least to 

 be considered: among the kinds thereof our country slate is not to be despised, 

 either for beauty, duration, or cheapness. The first sufficiently appears by the 



