A. When the rain-cloud is floating _near the earth_, the drops are large, because such a cloud is _much more dense_ than one which is more elevated. The size of the rain-drop is increased according to the _rapidity_ with which the vapours are condensed. Q. _Does not WIND sometimes INCREASE the SIZE of rain-drops?_ A. Yes; by blowing two or more drops into one. Q. _Why do CLOUDS FALL in RAINY weather?_ A. 1st--Because the _clouds are heavy_ with abundant vapour: and 2ndly--As the density of the air is _diminished_, it is less able to buoy the clouds up. Q. _How do you KNOW that the DENSITY of the air is DIMINISHED in RAINY weather?_ A. Because the _mercury of a barometer falls_. Q. _Why is RAIN-water more FERTILIZING than PUMP-water?_ A. Because it contains a compound of hydrogen and nitrogen (called _ammonia_), which is a very excellent food for young plants. Q. _Why is NOVEMBER made by God to be a RAINY MONTH?_ A. Because rain _hastens the putrefaction of the fallen leaves_ by causing fermentation. Q. _Why does RAIN PURIFY the AIR?_ A. 1st--Because it _beats down the noxious exhalations_ collected in the air, and _dissolves_ them: 2ndly--It mixes the air of the _upper_ regions with that of the _lower regions_: and 3rdly--It _washes the earth_, and sets in motion the stagnant _sewers and ditches_. Q. _Why are MOUNTAINOUS countries more RAINY than flat ones?_ A. The air (striking against the side of the mountains) is _carried up the inclined plane_, and brought in contact with the _cold air of the higher regions_, by which it is _condensed_, and its _vapour squeezed out_. Q. _Why does a SPONGE SWELL when it is WETTED?_ A. Because the water _penetrates the pores_ of the sponge, and drives the particles of the sponge _further from each other_; in consequence of which, the _bulk_ of the sponge is greatly _increased_. Q. _Why do FIDDLE-strings SNAP in WET weather?_ A. Because the moisture of the air (penetrating the string) _causes it to swell_; and (as the cord _thickens_) its _tension is increased_, and the string snaps. Q. _Why does PAPER PUCKER when it is WETTED?_ A. Because the moisture (penetrating the paper) _drives its particles further apart_; and (as the moisture is absorbed _unequally_ by the paper) some parts are more enlarged than others; in consequence of which, the paper _blisters_ or _puckers_. Q. _Why do the weather toys called CAPU'CHINS lift the cowl over the figures in wet weather, and remove it in dry?_ A. The cowl of the capu'chin is _fastened to a piece of cat-gut_. When the weather is _wet_, the moisture _swells the cat-gut_ and it is _shortened_, by which means the _cowl is pulled up_; but in _dry_ weather, the _string is loosened_, and the cowl falls down. Q. _In another weather toy, the MAN comes out in WET weather, and the LADY in FINE:--Why is this?_