2 86 Voyage of the Novara. 



unpleasant and severe months are June and July, although it 

 is at that period less the violence of the gales than the tre- 

 mendous sea, which occasionally hurls a ship, if not properly 

 made fast, into a position of danger, and occasionally inter- 

 rupts all communication with the shore for days together. A 

 season sometimes passes over, however, without the occur- 

 rence of any elemental strife. It would be of the highest in- 

 terest to be able to ascertain the periodicity of the return of 

 severe winters, which there can be little doubt obeys some 

 natural law. 



The barometer is, at Valparaiso, a pretty correct index of 

 the wind that may be expected. The more the mercury 

 sinks, the more perceptible will be the N. or N.W. wind. Rain 

 and foggy weather usually precede these winds, and continue 

 till the wind draws somewhat to the west, upon which the 

 mercury rises and the weather improves. North or north- 

 west winds are, however, as a rule never of long continuance, 

 and indeed frequently continue only a few hours, because so 

 soon as the first burst is over, the trade-wind, upon whose 

 limits it has encroached, soon begins to drive it before it, 

 under the influence of an air-wave from the southward, and 

 ships which, with the view of suffering as little as possible 

 from north or north-west winds, keep as far from the light- 

 house as possible, have nothing to dread from even a heavy 

 '' norther," if all proper precautions are taken, and their 

 anchors and cables hold.* 



* That ships in good holding ground and with sound tackle are in no great danger 



