INTRODUCTION. xxxiii 



rence to the gale of the 28th and 29th January, 1840. The position 

 of the squadron was as follows, viz. : 



The Porpoise encountered the gale first ; it began with the wind 

 from the eastward, and veered during its continuance to the south- 

 west by the south ; its duration was eighteen hours." The Vincennes 

 next experienced it, the storm undergoing the same changes as those 

 of the Porpoise; duration eleven hours. The Flying-Fish we find to 

 have encountered it next, the storm coming from the northeast and 

 veering to the southward ; duration twelve hours. The Peacock was 

 the last to encounter it, the storm beginning from the northwest, and 

 veering by west to the southwest, the most violent part of it after its 

 change ; duration was twenty-four hours. 



The distance of the Porpoise from the Vincennes was about 60 

 miles, which it passed over in 3 hours ; between the Vincennes and 

 Flying-Fish 260 miles, which it traversed in 13 hours; and the dis- 

 tance between the Vincennes and Peacock, about 400 miles, this space 

 was passed over in 21 hours, which gives its rate of progress about 20 

 miles an hour, and its track from west-southwest to east-northeast. 

 The centre of the storm must have passed between the vessels ; the 

 Vincennes, Porpoise, and Flying-Fish being to the south, while the 

 Peacock was to the north : this is known by the wind having veered 

 in opposite directions during the changes that took place while it 

 continued. 



SYDNEY TO NEW ZEALAND This passage was made in 13 days, in 

 the month of March. By the diagram, Plate XII., page 330, it will 

 be perceived that our route was nearly on the parallel of Sydney, and 

 that the temperature of both air and water was several degrees higher 

 than it had been in a lower latitude in the month of November, illus- 

 trating the influence of tropical currents between New Holland and 

 New Zealand during the summer months. The winds, after leaving 

 the coast, were quite variable, seldom remaining over a few hours 

 stationary. As we approached New Zealand, they were more constant 

 from the southwest; the temperature of the air varied between 64'4 

 and 71'6, that of the water between 68 and'72'5; the oscillations of 

 the barometer were '420 in.; the rise of the mercurial column taking 

 place with northerly winds, whilst it was depressed with southerly 



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