Scientific Intelligence. — Meteorology. S87 



the barrel itself moved a little, but this would have its inconve- 

 niences. I intend having an air-pump made on these principles, 

 and then to give a more particular description of its several 

 parts. H. Meikle. 



METEOROLOGY. 



Prognostics of the Weather. — Red clouds in the west, at sun- 

 set, especially when they have a tint of purple, portend fine 

 weather. The reason of which is, that the air, when dry, re- 

 fracts more red or heat-making rays ; and as dry air is not per- 

 fectly transparent, they are again reflected in the horizon. A 

 coppery or yellow sunset generally foretels rain ; but as an in- 

 dication of wet weather approaching, nothing is more certain 

 than the halo around the moon, which is produced by the pre- 

 cipitated water ; and the larger the circle the nearer the clouds, 

 and consequently the more ready to fall. The old proverb is 

 often correct : 



A rainbow in the morning is the shepherd's warning ; 



A rainbow at night is the shepherd's delight. 



A rainbow can only occur when the clouds, containing or de- 

 positing the rain, are opposite to the sun ; and in the evening 

 the rainbow is in the east, and in the morning in the west ; and 

 as our heavy rains in this climate are usually brought by the 

 westerly wind, a rainbow in the west indicates that the bad 

 weather is on the road, by the wind, to us ; whereas the rainbow 

 in the east proves that the rain in these clouds is passing from 

 us. When the swallows fly high, fine weather is to be expected 

 or continued ; but when they fly low, and close to the ground, 

 rain is almost surely approaching*. This is explained as fol- 

 lows : Swallows pursue the flies and gnats, and flies and gnats 

 usually delight in warm strata of air ; and as warm air is lighter, 

 and usually moister, than cold air, when the warm strata of our 

 air are high, there is less chance of moisture being thrown down 

 from them by the mixture with cold air ; but when the warm 

 and moist air is close to the surface, it is almost certain that, as 

 the cold air flows down into it, a deposition of water will take 

 place. When sea-gulls assemble on the land, stormy and rainy 



• Immediately before a thunder-storm this summer, and in the intervals of 

 the showers, swifts and martins were observed to fly very high :— and so of 

 many other prognostics.— M. 



B b2 



