160 BERTHA'S VISIT TO HER 



tain time. Swallows and martins indeed sprinkle 

 and splash themselves j as they glide along 

 the surface, but they never dip completely 

 into the water for a single moment. At the 

 season when tfiey disappear there is no want of 

 their insect food in the air; nor have any of 

 those cold blasts come, which at a later period 

 would benumb them ; what, then, could induce 

 them, particularly the young birds who have just 

 begun to enjoy the use of their wings, to take a 

 dreary plunge into a pond ? Cold and scarcity 

 may drive some animals to hibernate, like your 

 little dormouse, Bertha, but I am satisfied that 

 the whole tribe of swallows fly off, like other birds 

 of passage, to distant countries." 



" To what countries ?" I asked him. 

 " It is probable," he replied, (( that there is 

 some general temperature that suits them best, or 

 that is most productive of those insects on which 

 they prey ; and as the seasons change, that tem- 

 perature can only be obtained by approaching 

 the equator, or perhaps by passing into a corre- 

 sponding latitude of the southern hemisphere. 

 A circumstance mentioned by our friend Colonel 

 Travers, made a strong impression on me : 

 when he was going up the Mediterranean, I 

 think in the latter end of April, a great number 

 of swallows settled on the yards and rigging of 

 the ship ; they began to alight there about sun- 

 set, and before nine o'clock some thousands had 



