34 EIGHTH REPORT — 1838. 



the Helm for a whole day without being aware of the wind on the west. 

 The Helm appears sometimes to run or pour off from the highest 

 part, each way towai'ds the north and south points of the junction of 

 the Helm and Bar, and there to be piled up in great masses ; occa- 

 sionally a Helm forms and goes off without a blast. The open space 

 between the Helm and Bar is clear of clouds, with the exception of small 

 pieces breaking off now and tlicn from the Helm and driving rapidly 

 over to the Bar ; through this open space is often seen a higher stratum 

 of clouds quite at rest. 



Most mountainous countries, particularly where the mountains ter- 

 minate abruptly, seem liable to sudden gusts of wind, such as occur at 

 the Cape of Good Hope, in Switzerland, and among the lakes in our 

 own country; but the Helm wind differs from all in respect to the Bar, 

 and that within the space described it blows continually ; it has been 

 known to blow for nine days together, the Bar advancing or receding, 

 or continuing stationary for a day. When heard and felt for the first 

 time it does not seem so very extraordinary ; but when we find it 

 blowing and roaring morning, noon, and night, for days together, it 

 makes a strong impression on the mind, and we are compelled to ac- 

 knowledge that it is one of the most singular phenomena of meteorology. 

 Its sound is peculiar, and when once known is easily distinguished from 

 that of ordinary winds ; it cannot be heard more than three or four 

 miles beyond its limit, but by persons who have stood within the wind 

 or near it, it has been compared to the noise made by the sea in a vio- 

 lent storm, or that of a large cotton mill when all the machinery is 

 going. It is seldom accompanied by rain within the open space, and 

 never continues long after it begins to rain heavily; in spring, it is 

 most frequent after rain. The countrj' subject to it is very health}', 

 but the wind does great injury to vegetation, as it batters the grain, 

 grass, and the leaves of trees till they are quite black. Various hypo- 

 theses have been suggested to account for this phenomenon ; one of 

 the most plausible assumes that the air is cooled by its gradual ascent 

 from the east coast, and on reaching the summit of the mountains, 

 rushes with great force down the Avestern escarpment into a lower and 

 warmer region. In opposition to this it is stated, that the valley of the 

 Tyne, a\ here the Helm Avind is not felt, is not much higher than that 

 of the Eden ; and secondly, the wind does not extend farther west than 

 where the Bar is vertical, and this is not very often so far as the Eden. 

 The cause, Mr. Watson thinks, must be sought for in that region of 

 the atmosphere, extending from 800 to about 5000 feet above the 

 earth's surface. 



On the Temperatures observed in certain Mines in Cheshire. By 

 Eaton Hodgkinson, Esq. 



(The results will be given hereafter in combination with the account 

 of other experiments.) 



