The Northern Eccpeditions. 229 



classes; and, as might be expected, various tlioughts have been 

 offered to the public in different forms, bearing upon this subject. 

 The state of our climate for a long series of years has been inves- 

 tigated, and, in the Journal of the Royal Institution, great influ- 

 ence has been ascribed to the Greenland ice. Tlie same argu- 

 ment has since appeared in the Quarterly Review from the pen 

 of Mr. Barrow, who has produced a most interesting paper on 

 the subject. His conclusions, however, are questioned Ijy many; 

 and it is probable the investigation which has thus counnenced, . 

 may lead to the publication of various useful papers on the causes 

 of periodical changes in the temperature of clim:it*s. On the 

 physical Liws which cooperate, we have inserted, in a preceding 

 part of this number, a short but interesting paper from a corre- 

 spondent under the sitrnature of Z. A. to which we here add the 

 following observations copied from the Glasgow Chronicle. 



Mr. Barrow contends that " oar climate, in the course of the 

 last three yeai-s, has been particularly afifected" by " the appear- 

 ance of ice in the Atlantic;" that "in the summers of 1815, 

 1816, and 1817, more particnlarlv in the two last, islands of ice, 

 unusual in size and immber, were seen as far down as the 40th 

 parallel of latitude;" that one of the islands of ice was twt) miles 

 in circumference, and 200 feet in height; that othej-s weie several 

 miles in circumference ; that Newfoundland during last summer 

 was comi)letely environed with ice; that greater quantities ex- 

 isted then in that quarter than were ever befote observed ; that 

 " during the last two summers the mercurv invariably fell with 



westerly winds ; " and that it can scarcely !)e doubted that the 

 .late coldness of the seasons was produced by an atmosphere, 

 chilled and condensed over ice-bergs and ice-islands, " nisliiug . 



directly upon the Britisli islands from the westward." 



In proof of the coldness of the last three summers Mr. Barrow 



contrasts their temperatures with those of 1805, ISOG, and 1807. 



Tbc mean results are as follows: — 



lbO.7 :i\)'6 1806 62-3 1S07 62-85 



\^\-o 61-55 1816 57-8 1817 5873 



This statement of itself refutes Mr. Barrow's s])ecuiation. One 



of his cold years is 2*25 warmer than one of his warm ones, and 



the otlier two are only 1-5 and -55 colder. In 1805, when there 



were noice-liergs, the mean temperature of the summer was 59*3. 



In 1815, when there were ice-bergs, the temperature was 61*55. 



Wherefore, according to the Quarterly Review, the ice-bergs have 



chilled the climate! 



It is true that 1806 and 1807 were 4-5 and 4*1 warmer than 



1816 and 1817, but 1805 was scarcely any warmer; and if the 



temperature of that summer was not influenced by ice, how shall 



Mr. Barrow say that it affected 1816 and 1817 ? 



P 3 The 



