WEATHER. 



The wtermediait modifications which require 

 lo be noticed are 4. Cirro-cumulus ; small, 

 welt-defined, roundish masses, in close horizon- 

 tal arrangement 6. Cirro-stratus ; horizontal 

 or slightly inclined masses, attenuated towards 

 a part or the whole of their circumference, bent 

 downward, or undulated, separate or in groups, 

 consisting of small clouds having these cha- 



The compound modifications are 6. Cumulo- 

 the cirro-stratus blended with the cu- 

 and either appearing intermixed with 

 the heaps of the latter, or superadding a wide- 

 spread structure to its base. 



um*lo-cim>*tratus t vel Nimbus; the rain 

 cloud, a cloud or system of clouds from which 

 rain is falling; it is a horizontal sheet, above 

 which the cirrus spreads, while the cumulus 

 enters it laterally and from beneath. 



The nma appears to have the least density, 

 the greater variety of extent and direction, and 

 lo appear earliest, in serene weather, being in- 

 dicated by a few threads pencilled in the sky. 

 Before storms they appear lower and denser, 

 and usually in the quarter opposite to that from 

 which the storm arises. Steady high winds 

 Are also preceded and attended by cirrus streaks 

 running quite across the sky in the direction 

 they blow in. 



The cnmuhu has the densest structure, is 

 formed in the lowest atmosphere, and moves 

 along with the current next the earth ; a small 

 irregular spot first appears, and is as it were 

 ihr nucleus on which they increase. The lower 

 surface continues irregularly plain, while the 

 upper rises into conical or hemispherical heaps, 

 which may afterwards continue long nearly of 

 the same bulk, or rapidly rise into mountains : 

 they will begin in fair weather to form some 

 hours after sunrise, arrive at their maximum 

 in the hottest part of ihe afternoon, then go on 

 diminishing, and totally disperse about sunset. 

 r.-iin the cumulus increases rapidly, 

 appears lower in the atmosphere, and with its 

 surface full of loose fleeces or protuberances. 

 The formation of large cumuli to leeward in a 

 strong wind indicates the approach of a calm 

 <in ; when they do not disappear or sub- 

 side about sunset, but continue to rise, thunder 

 is to be expected in the night. The stratus has 

 a mean degree of tensity, and is the lowest of 

 clouds, its inferior surface commonly resting 

 on the earth or water. This is properly the 

 uht, appearing about sunset. It 

 iprehends all those creeping mists which in 

 calm weather ascend in spreading sheets (like 

 idation of water) from the bottom of 

 ratters and the surfaces of lakes and rivers. 

 On the return of the sun the level surface of 

 this cloud begins to put on the appearance of 

 nwwlw, the whole at the same time separating 

 from the ground. The continuity is next de- 

 stroyed, and the cloud ascends and evaporates, 

 or passes off with the appearance of nascent 

 cumulus. This has long been experienced as 



of fair weaiher. 



e nmw having continued for some time 



reasmg or stationary, usually passes either 



to the amxMmWta* or the cirro-stratus, at the 



ime descending to a lower station in the 



atmosphere. This modification forms a very 



1116 



WEATHER. 



beautiful sky, and is frequent in summer, as 

 an attendant on warm and dry weather. The 

 cirro-stratus, when seen in the distance, fre- 

 quently gives the idea of shoals of fish (a 

 mackerel sky). It precedes wind and rain; is 

 seen in the intervals of storms, and sometimes 

 alternately with the cirro-cumulus in the same 

 cloud, when the different evolutions form a cu- 

 rious spectacle. A judgment may be formed 

 of the weather likely to ensue, by observing 

 which modification prevails at last. The solar 

 and lunar halos, as well as the parhelion and 

 paraseline (mock sun and mock moon), prog- 

 nostics of foul weather, are occasioned by this 

 cloud. The cumulo-stratus precedes, and the 

 nimbus accompanies rain. 



When there are small round clouds, of a 

 dapple-gray colour, with a north wind, it may 

 be concluded that there will be fair weather for 

 2 or 3 days, but that large clouds like rocks 

 are a sign of great showers. And when small 

 clouds increase, it is a sign that there will be 

 much rain, but if the large clouds are seen to 

 lessen, there will be fair weather. 



In summer or harvest, when the wind has 

 been south 2 or 3 days, and it grows very hot, 

 and clouds are seen to rise with great white 

 tops like towers, as if one were on the top of 

 another, and joined together Avith black on the 

 lower side, it may be considered a sign that 

 there will be thunder and rain suddenly. When, 

 two such clouds rise, one on each hand, it is 

 time to make haste to shelter. 



When a cloud is seen to rise against the 

 wind or side wind, it is a sure sign that when 

 the cloud conies up near you, the wind will 

 blow the way that the cloud came. It is the 

 same with the motion of a clear place, when 

 all the sky is thick except one edge. 



At all times, when the clouds look black in 

 the west, it is sure to rain, or if raining, it is 

 sure to continue, whatever quarter the wind 

 may be in ; and, on the contrary, if it breaks 

 in the west, it is sure to be fair. 



It is often observed, on those clear sunny 

 mornings which occur in summer and autumn, 

 that it is very likely, if not certain, to rain be- 

 fore evening; and there is frequently much 

 truth in the remark. The reason is, that when 

 moisture accumulates in the air, before it be- 

 gins to be precipitated, it imparts to it a higher 

 refractive power; and it becomes, in conse- 

 quence, more bright and transparent. (British 

 Almanac, 1830.) 



The gradual diminution of clouds, till they 

 are no longer observable, is a sign also of fine 

 weather. So, likewise, is the continuance or 

 abundance of dew upon the grass, after a 

 serene day. 



During winter, fleecy clouds being thick and 

 close in the middle, and very white at the 

 edges, the surrounding sky being remarkably 

 blue, indicate hail or snow, or cold, chilling, 

 showers of rain. 



Where the clouds appear moving in two op- 

 posite currents, and the lowest is wafted rapidly 

 before the wind, it is a certain sign of rain ; 

 and if this occurs during summer, or generally 

 in hot weather, ii announces a thunder-storm. 



It may be a useful piece of information for 

 agriculturists, or those concerned in getting in 



