SCIENCE-GOSSJ]\ 



isobarie charts, as they are sometimes called, 

 quickly reveals the fact that the shapes assumed 

 by these isobars vary with the type of weather. 

 Thus during stormy, rainy weather the isobars are 

 crowded together, the barometer readings being 

 lowest at the centre of the disturbance, the condi- 

 tions being called " cyclonic." On the other hand, 

 when the weather is fine and the wind slight in 

 force, the isobars are far apart, and the highest 

 barometer readings are to be found at the centre, 

 the conditions being then called "anti-cyclonic." 

 Roughly sxseaking, therefore, all types of weather 

 are either cyclonic or anti-cyclonic ; so in looking 

 at a weather map it will be noticed that the 

 cyclones occupy one part of the country and the 

 anti-cyclones another, and the kind of weather to 

 be expected depends on the relative positions of 

 these two systems to one another. In forecasting 

 the weather, therefore, by the aid of such charts, 

 it is as if one had to foretell the future positions of 

 the pieces on a chess-board ; for the cyclones and 

 anti-cyclones move at varying rates, and it is not 

 surprising, therefore, that in compiling his forecasts 

 the weather-prophet sometimes makes mistakes. 

 A further important fact is that each quadrant 

 in a cyclone, and in an anti-cyclone also, has 

 certain definite kinds of weather associated with 

 it ; and it is this circumstance which explains the 

 success of many popular weather prognostics 

 based on the movements of birds and animals, and 

 on such things as haloes and sunset colours. The 

 front of a cyclone or depression, as it is sometimes 

 termed, is always associated with a rising tem- 

 perature and damp weather ; while as the storm 

 departs, temperature falls and the wind flies round 

 to a dry quarter. It is therefore not surprising 

 that as the cyclone advances, the dampness of 

 the atmosphere causes certain birds, quadrupeds, 

 insects, and flowers to exhibit an unusual amount 

 of restlessness ; the closing of petals on the part 

 of flowers, and unwonted migrations on the part of 

 animals, being solely due to the hygrometric con- 

 dition of the atmosphere produced by a coming 

 storm. There is therefore reason to expect bad 

 weather when these movements are observed, since 

 they simply mean that the front part of a cyclone 

 has arrived, and the usual sequence of rainy 

 weather may be expected to follow. Most people, 

 again, are familiar with the feathery wisp-like 

 cloud called cirrus, which is invariably associated 

 with the forefront of a cyclone. When the weather- 

 prophet sees this cloud he is sure that stormy 

 weather is near at hand. Cirrus, the highest of 

 all clouds, is probably composed of ice crystals, 

 and it is these that act like prisms, causing the 

 haloes which during bad weather form round the 

 sun and moon. 



Time out of mind haloes have been popular 

 prognostics for stormy weather, and receive sanc- 

 tion from the weather charts, for they simply 

 mean that cirrus cloud is forming, or, in other 



winds, that the front of a cyclone has arrived; 



A similar comparison shows thai when people 

 forecast rainy weather from the flaring of lamps 

 ami candles, from rheumatic pains, shooting corns, 

 and creaking furniture, the indications are the 

 same ; for all these phenomena are to be set down 

 to the ci-edit of the high temperature and in- 

 creased moisture which are associated with the 

 front portion of a cyclonic system. In the same 

 way the bawling of peacocks, the braying of asses, 

 the occasionally excessive quacking of ducks, and 

 an unusual activity and brilliance of glowworms, 

 which are all popular prognostics for rainy weather, 

 probably have gained their popularity from the 

 fact that they manifest themselves at such times 

 as atmospheric pressure is decreasing and moisture 

 increasing. 



As already mentioned, fine-weather conditions 

 are called anti-cyclonic, and the prominent features 

 . of this kind of weather are dew and mist in the 

 morning, brilliant midday sunshine, with mist 

 again during the evening hours. At such times, 

 also, the barometer stands high, and it is not sur- 

 prising that under the exhilarating influences- of a 

 blue sky and gentle breezes birds fly high and go 

 far afield, and animals and insects show an ab- 

 normal activity. Bird-catchers know that when 

 larks fly high and swallows soar aloft in the em- 

 pyrean a continuance of fine weather may be 

 expected. Owls hooting in the stilly night are not 

 pleasant to those suffering from insomnia ; but 

 there is consolation in the thought that such hoot- 

 ings betoken the formation of an anti-cyclone and 

 subsequent fine weather. Indeed, concerning anti- 

 cyclonic conditions there are a very large number 

 of popular prognostics which have reference to fine 

 weather, and some of these proverbs and weather 

 saws have been in use during many centuries. 

 Modern meteorology, moreover, does not seek to 

 discountenance the use of this folk-lore, since it 

 can be shown, as above, that it owes its success to 

 the fact that these prognostics agree with the con- 

 clusions arrived at by more scientific methods. 

 The meaning, therefore, of all these fine- weather 

 prognostics is that the birds, insects, and other 

 animals are active and lively because the atmo- 

 spheric conditions are anti-cyclonic. 



Cyclones and anti-cyclones, however, are not 

 always of the same size and shape ; and as they 

 drift through the atmosphere they get squeezed 

 and distorted, spreading out in unexpected direc- 

 tions. Two cyclones, for instance, may be separat ed 

 by a very narrow anti-cyclone. As this "anti-cyclonic 

 wedge," as it is sometimes called, passes over the 

 country the birds or other animals commence all 

 those movements which the weather-wise associate 

 with fine weather, and the prophets say that fine 

 weather is coming. Yet. since this wedge of 

 high pressure is so narrow, the fine weather 

 la^ts only an hour or so. and cyclonic and stormy 

 weather quickly follows. This is an instance 



