656 THE POPULAR SCIENCE MONTHLY. 



With the gloomy, close, and muggy weather, some people are 

 troubled with rheumatic pains and neuralgia, old wounds and corns 

 are painful, animals and birds are restless, and drains and ditches give 

 out an offensive smell. 



A glance at the diagram will show that the barometer falls during 

 the whole of the front of the cyclone. Therefore the explanation of 

 the universally known fact that the barometer generally falls for bad 

 weather is, that both rain and wind are usually associated with the 

 front of a cyclone. When we discuss secondaries, we shall find a kind 

 of rain for which the barometer does not fall ; and in our chapter on 

 forecasting for solitary observers we shall explain why it sometimes 

 rains while the barometer is rising, and why there is sometimes fine 

 weather while the mercury is falling. 



Now, to take prognostics which belong to different portions of the 

 cyclone-front. By reference to Fig. 2 it will be seen that in the out- 

 skirts of the cyclone- front there is a narrow ring of halo-forming sky. 

 Hence the sayings : "Halos predict a storm (rain and wind, or snow 

 and wind) at no great distance, and the open side of the halo tells the 

 quarter from which it may be expected." "Mock suns predict a more 

 remote and less certain change of weather." 



Inside the halo sky comes the denser cloud Avhich gives the pale 

 watery sun and moon. Still nearer the center we find rain, first in the 

 form of drizzle, then as driving rain. In the left front we find ill- 

 defined showers and a dirty sky. 



We have now come to the trough of the cyclone. The line of the 

 trough is often associated with a squall or heavy shower, commonly 

 known as " a clearing shower." This is much more marked in the 

 portion of the trough which lies to the south of the cyclone's center 

 than on the northern side. 



Then we enter the rear of the cyclone. The whole of the rear is 

 characterized by a cool, dry aii', with a brisk, exhilarating feel, and a 

 bright sky, with hard cumulus cloud. These features are the exact 

 converse of those we found in the cyclone-front. In the cloud-forms 

 especially we see this difference. All over the front, whether high up 

 or low down, whether as delicate cirrus or heavy gloom, the clouds 

 are of a stratified type. Even under the rain, when we get a peep 

 through a break in the clouds, we find them lying like a more or less 

 thick sheet over the earth. All over the rear, on the contrary, clouds 

 take the rocky form known as cumulus ; cirrus is almost unknown in 

 the rear of a cyclone-center in the temperate zone. 



In the exhilarating quality of the air we find the meaning of the 

 proverb, " Do business with men when the wind is in the northwest," 

 A northwest wind belongs to the rear of a cyclone, and improves men's 

 tempers, as opposed to the neuralgic and rheumatic sensations in front 

 of a cyclone, which make them cross. 



As to the details of the different portions of the rear. Immediately 



