A. Those clouds which assume all sorts of _gigantic fancy forms_; such as vast towers and rocks,--huge whales and dragons,--scenes of battle,--and cloudy giants. This class of clouds is the most romantic and strange of all. Q. _What do the cumulo-stratus clouds foretell?_ A. _A change of weather_; either from fine to rain, or from rain to fine weather. Q. _What are NIMBUS CLOUDS?_ A. Nimbus is the Latin word for "clouds which bring a storm;" and all clouds from which _rain falls_ are so named. Q. _What APPEARANCE takes place in the CLOUDS at the approach of RAIN?_ A. The _cum'ulus_ cloud becomes _stationary_, and _cirrus streaks settle upon it_, forming cumulo-stratus clouds; which are _black_ at first, but afterwards of a _grey_ colour. Q. _Why do CLOUDS gather ROUND MOUNTAIN-TOPS?_ A. Because (as they float along) _they dash against the mountains_; and (being _arrested_ in their motion) collect round the top. Q. _What is the USE of CLOUDS?_ A. 1st--They act as screens to arrest _the radiation of heat from the earth_: 2ndly--They temper the heat of the _sun's rays_: and 3rdly--They are the great _store-houses of rain_. Q. _Why is WIND said to BLOW UP the CLOUDS?_ A. When a _dry_ wind travels over sea, and accumulates _more_ vapour than the air can _sustain_, it _relinquishes a part_ (as it flies along) in the form of clouds. Q. _Why does WIND sometimes DRIVE AWAY the CLOUDS?_ A. When wind travels over _dry climes_ or _thirsty deserts_, it becomes _so dry itself_, that it absorbs vapour from the clouds, and _disperses_ them. Q. _What is the CAUSE of a RED SUN-SET?_ A. Because the vapour of the air is not _actually condensed into clouds_, but only on the _point of being condensed_; in which state it bends the _red rays of the sun towards the horizon_, where they are reflected at sun-set. Q. _Why is a RED SUN-SET an indication of a FINE DAY to-morrow?_ A. Because (notwithstanding the cold of sun-set) the vapours of the earth are _not condensed into clouds_. Our Lord referred to this prognostic in the following words: "When it is evening ye say, it will be fair weather, for the sky is red." (Matt. xvi. 2.) Q. _What is the cause of a coppery YELLOW SUN-SET?_ A. Because the vapour of the air is _actually condensed into clouds_; in which case it "refracts" (or bends) the _yellow rays of the sun towards the horizon_, where they are reflected at sun-set. Q. _Why is a YELLOW SUNSET an indication of WET?_ A. Because the vapours of the air _are already condensed into clouds_; rain, therefore, may be shortly expected. Q. _What is the cause of a RED SUN-RISE?_ A. Vapour in the upper region of the air _just on the point of being condensed_. Q. _Why is a RED and LOWERING sky at SUNRISE an indication of a WET DAY?_