A. When water freezes it _gives out its latent heat_, in order that it may be converted into _solid ice_; and as much _heat is liberated_ from the water into the air, we feel warmer. Q. _Why does SALT DISSOLVE ICE?_ A. Water freezes at 32°, but salt and water will not freeze _till the air is 25° colder_: if, therefore, salt be added to frozen water it becomes _liquid_, unless the thermometer stands below 7°, (which it never does in our island). Q. _Will any thing do INSTEAD of SALT?_ A. Yes; any _acid_, such as sulphuric, nitric, &c. Q. _Why are SALT and SNOW mixed together, colder than SNOW?_ A. When _salt_ is mixed with snow, it _dissolves the crystals_ into a fluid; and whenever a solid is converted to a liquid, _heat is absorbed_, and the cold made more intense. Q. _Why does FROST make the EARTH CRACK?_ A. During the warm weather the earth _absorbed abundance of moisture_, which the winter _freezes_: and (as water _expands_ by frost) the expanding water _thrusts the particles of earth apart from each other_, and leaves a chink or crack behind. Q. _Show the WISDOM of GOD in this arrangement._ A. These _cracks_ in the earth let in the air, the dew and rain, and many gases favourable to vegetation. Q. _Why does the EARTH CRUMBLE in SPRING?_ A. In spring the _ice_ of the clods _dissolves_, and the particles of earth (which had been held apart by the expanded ice) are left _unsupported_, and tumble into minute parts (because their _cement is dissolved_). Q. _Why does MORTAR CRUMBLE away in FROST?_ A. If the mortar was not _dried in the warm weather_, its moisture _freezes_, _expands_, and thrusts the particles of the mortar away from each other; but (as soon as the frost goes) the _water condenses_ and leaves the mortar full of cracks and chinks. Q. _Why does STUCCO PEEL from a WALL in FROSTY weather?_ A. If the stucco was not _dried in the warm weather_, its moisture _freezes_, _expands_, and thrusts its particles away from the wall; but as soon as the water condenses again by the thaw, the stucco (being unsupported) _falls by its own weight_. Q. _Why cannot BRICKLAYERS and PLASTERERS work in FROSTY weather?_ A. Because the bricks and plaster would _start from their position_ as soon as the _frost_ came and expanded the mortar. Q. _Why do BRICKLAYERS COVER their work with STRAW in spring and autumn?_ A. Because straw is a non-conductor, and prevents the mortar of their new work from _freezing_ during the cold nights of spring and autumn. Q. _Why are WATER-PIPES often covered with STALL-LITTER in winter time?_ A. Because straw (being a non-conductor) prevents the _water of the pipes from freezing_, and the _pipes from bursting_. Q. _Why are delicate TREES covered with STRAW in WINTER?_ A. Because straw (being a non-conductor) prevents the _sap of the tree_ from being frozen. Q. _Can WATER be FROZEN in any way BESIDES by frosty weather?_