THE AFRICAN MONSOONS. 159 



n\iiner of a heavy squall ; it is a monitor whose warning should not be 

 neglected.* 



Whenever there is much lightning, and the wind is unsteady and baffling 

 about, prepare for a change. A heavy dense cloud, having a squally 

 appearance, may rise and pass slowly over the vessel directly to leeward, 

 with perhaps little or no increase of wind ; and when the danger may be 

 supposed over, the vessel is suddenly taken aback with a smart squall. 

 This, I presume, arises from the cloud which has just gone over the ship, 

 being opposed in its progress to leeward by a sti'onger current of air from 

 the opposite quarter. On this account, when clouds are in motion from 

 opposite quarters of the compass, a better look-out, if possible, should be 

 kept to leeward than to windward. 



Keeping a good look-out upon the surface of the water is an excellent 

 method of judging of the force of the wind in an approaching squall ; but, 

 on account of the heavy rain which invariably accompanies the squalls 

 alluded to, very little sound judgment can be exercised with respect to their 

 strength ; they are generally, however, tolerably heavy, and require sail to 

 be considerably reduced. 



In June, July, and August, the weather is very wet and squally. Some- 

 times dense masses of clouds are seen in rapid motion from the S.E., 

 Southern, and S.W. quarters of the horizon : these clouds have a bulky 

 and confused appearance, as if tumbling or rolling over each other ; are of 

 a dirty dark drab colour, with ragged edges, and inky-looking small clouds 

 flying about the edges of them. In their approach towards the zenith they 

 gradually appear to unite and form the apex of an angle, and, thus united, 

 blow with incredible violence from the S.W. quarter (veering about two or 

 three points or more) for upwards of two hours, during which time the rain 

 descends in torrents, perhaps accompanied by a waterspout or whirlwind. 



Ships should be weU prepared for these dangerous visitors ; for they como 

 with a similar violence to the Arched White Squall of the West Indies. I 

 have experienced two squalls of the above description (both in the month 

 of July), and in one of them lost a good fore-topsail, after the reef tackles, 

 &c., were hauled out snug, and the ship had been for some time running 

 directly before the wind. Upon both occasions my barometer fell three- 

 tenths of an inch very suddenly, which enabled me to take in sail in time ; 

 for the squalls did not look particularly alarming until about eight or ten 

 minutes before they reached the ship. 



To the inexperienced in this part of the ocean, I would beg to remark, 

 that much sheet lightning is always suspicious, and forked or chain lightning 

 universally so ; and the latter is, in some degree, indicative of a change, 

 as of an increase of wind. 



After the wind has blown steadily, with fine weather for a few hours, 

 and it then begins to be variable, and fly suddenly about, squalls and rain 

 may be expected. 



• In those parts of tiie North Atlantic Ocean which are not in the general influeme ot 

 the Trades, I have very frequently remarked that lightning is indicative of a change of 

 wind. 



