36 GLACIAL GROOVES. [CHAP. II 



on the wing 1 , floating gently in the air, or darting rapidly after 

 insects. Thousands of these birds, with their young, died in 

 their nests in the spring of 1836, during a storm of cold rain, 

 which lasted two weeks, and destroyed the insects throughout 

 the states of New York and New England. The smaller species 

 (Hifundo vi/ridis) then regained possession of their old haunts, 

 occupying the deserted houses of the more powerful species, which, 

 like the house-sparrow in Europe, has followed the residence of 

 man. 



The sun was very powerful at noon ; but the severity of the 

 cold here in winter is so great, that a singular effect is produced 

 in the Piscataqua when the thermometer sinks to 15 below zero. 

 The tide pours into the estuary a large body of salt water par 

 taking of the warmer temperature of the gulf stream, and this 

 water, coming into the colder atmosphere, smokes like a thermal 

 spring, giving rise to dense fogs. 



I had been desirous of making the acquaintance of Mr. Hayes, 

 in consequence of having read, before I left England, an excellent 

 paper published by him in the Boston Journal of Natural History, 

 for 1844, on the Antarctic Icebergs, considered as explanatory 

 of the transportation of rocky masses, and of those polished rocks 

 and glacial grooves and strise before alluded to. He had derived 

 his information from experienced men engaged in the southern 

 whale fisheries, principally merchants of New Bedford, Massa 

 chusetts, and Stonington, Rhode Island. On looking over his 

 original MS. notes, I found he had omitted to print some parti 

 culars of the evidence, which I consider of no small interest as 

 throwing light on a class of geological appearances hitherto 

 thought least reconcilable with the ordinary course of nature. 

 As to the carriage of huge fragments of rock for many hundreds 

 of miles, from one region to another, such transportation was 

 formerly appealed to by writers now living as among the marvels 

 of the olden time, resembling the feats of the fabulous ages, and 

 as much transcending the powers of nature in these degenerate 

 days, as the stone hurled by Hector against the Grecian gate, 

 exceeded in weight and size what could now be raised from the 

 ground by two of the strongest of living men (oloi vvv (3poroi). 



