Q.What is the difference between amistandfog?A.Mistis generally applied tovapours condensed on marshes, rivers, andlakes.Fogis generally applied tovapours condensed on land, especially if those vapours areladen with smoke.
Q.What is the difference between amistandfog?
Q.What is the difference between amistandfog?
A.Mistis generally applied tovapours condensed on marshes, rivers, andlakes.Fogis generally applied tovapours condensed on land, especially if those vapours areladen with smoke.
A.Mistis generally applied tovapours condensed on marshes, rivers, andlakes.
Fogis generally applied tovapours condensed on land, especially if those vapours areladen with smoke.
Q.What is the reason why condensed vapour sometimes forms intoclouds, and sometimes intofog?A. If the surface of theearthbehotter than the air, then the vapour of the earth (being chilled by the cold air) becomesfog: but if theairbehotter than the earth, the vapourrises through the air, and becomescloud.
Q.What is the reason why condensed vapour sometimes forms intoclouds, and sometimes intofog?
Q.What is the reason why condensed vapour sometimes forms intoclouds, and sometimes intofog?
A. If the surface of theearthbehotter than the air, then the vapour of the earth (being chilled by the cold air) becomesfog: but if theairbehotter than the earth, the vapourrises through the air, and becomescloud.
A. If the surface of theearthbehotter than the air, then the vapour of the earth (being chilled by the cold air) becomesfog: but if theairbehotter than the earth, the vapourrises through the air, and becomescloud.
Q.If cold air producesfog, why is it not foggy on afrosty morning?A. 1st—Becauseless vapour is formed on a frosty day; and2ndly—The vapouris frozen upon the groundbefore it can rise from the earth, and becomeshoar-frost.
Q.If cold air producesfog, why is it not foggy on afrosty morning?
Q.If cold air producesfog, why is it not foggy on afrosty morning?
A. 1st—Becauseless vapour is formed on a frosty day; and2ndly—The vapouris frozen upon the groundbefore it can rise from the earth, and becomeshoar-frost.
A. 1st—Becauseless vapour is formed on a frosty day; and
2ndly—The vapouris frozen upon the groundbefore it can rise from the earth, and becomeshoar-frost.
Q.Why arefogsmore general inautumnthan in spring?A. In springthe earth is not so hotas it is in autumn. Inautumntheearthis generallywarmer than the air; and, therefore, the vapour (issuing from the earth)is condensed into fogby the chill air.
Q.Why arefogsmore general inautumnthan in spring?
Q.Why arefogsmore general inautumnthan in spring?
A. In springthe earth is not so hotas it is in autumn. Inautumntheearthis generallywarmer than the air; and, therefore, the vapour (issuing from the earth)is condensed into fogby the chill air.
A. In springthe earth is not so hotas it is in autumn. Inautumntheearthis generallywarmer than the air; and, therefore, the vapour (issuing from the earth)is condensed into fogby the chill air.
Q.Why arefogsmore common invalleysthan onhills?A. 1st—Because valleyscontain more moisture than hills: and2ndly—They arenot exposed to so much wind, (which dissipates the vapour).
Q.Why arefogsmore common invalleysthan onhills?
Q.Why arefogsmore common invalleysthan onhills?
A. 1st—Because valleyscontain more moisture than hills: and2ndly—They arenot exposed to so much wind, (which dissipates the vapour).
A. 1st—Because valleyscontain more moisture than hills: and
2ndly—They arenot exposed to so much wind, (which dissipates the vapour).
Q.How doeswinddissipatefogs?A. Either byblowing them away; or else bydissolving them into vapour again.
Q.How doeswinddissipatefogs?
Q.How doeswinddissipatefogs?
A. Either byblowing them away; or else bydissolving them into vapour again.
A. Either byblowing them away; or else bydissolving them into vapour again.
Q.What ishoar-frost?A. There are two sorts of hoar-frost: 1.—Frozen dew: and 2.—Frozen fog.
Q.What ishoar-frost?
Q.What ishoar-frost?
A. There are two sorts of hoar-frost: 1.—Frozen dew: and 2.—Frozen fog.
A. There are two sorts of hoar-frost: 1.—Frozen dew: and 2.—Frozen fog.
Q.What is the cause of thegroundhoar-frost, or frozendew?A. Veryrapid radiation of heat from the earth; in consequence of which, thesurface is so cooled down, that itfreezes the dewcondensed upon it.
Q.What is the cause of thegroundhoar-frost, or frozendew?
Q.What is the cause of thegroundhoar-frost, or frozendew?
A. Veryrapid radiation of heat from the earth; in consequence of which, thesurface is so cooled down, that itfreezes the dewcondensed upon it.
A. Veryrapid radiation of heat from the earth; in consequence of which, thesurface is so cooled down, that itfreezes the dewcondensed upon it.
Q.Why ishoar-frostseen only after a veryclear night?A. Unless the night has been very clear indeed, the earth will not have thrown off heat enough by radiation, tofreezethe vapour condensed upon its surface.
Q.Why ishoar-frostseen only after a veryclear night?
Q.Why ishoar-frostseen only after a veryclear night?
A. Unless the night has been very clear indeed, the earth will not have thrown off heat enough by radiation, tofreezethe vapour condensed upon its surface.
A. Unless the night has been very clear indeed, the earth will not have thrown off heat enough by radiation, tofreezethe vapour condensed upon its surface.
Q.Why doeshoar-frostvery oftencoverthegroundandtrees, when the water of rivers is not frozen?A. Hoar-frost is not the effect of cold in theair, but the cold of theearth(produced by excessive radiation); in consequence of which,the dew(condensed upon it)is frozen.
Q.Why doeshoar-frostvery oftencoverthegroundandtrees, when the water of rivers is not frozen?
Q.Why doeshoar-frostvery oftencoverthegroundandtrees, when the water of rivers is not frozen?
A. Hoar-frost is not the effect of cold in theair, but the cold of theearth(produced by excessive radiation); in consequence of which,the dew(condensed upon it)is frozen.
A. Hoar-frost is not the effect of cold in theair, but the cold of theearth(produced by excessive radiation); in consequence of which,the dew(condensed upon it)is frozen.
Q.Why is thehoar-frostupongrassandvegetablesmuch thicker than that upon loftytrees?A. Because the air (resting on thesurface of the ground) is much colder after sun-set, than theair higher up;in consequence of which, more vapour is condensed and frozen there.
Q.Why is thehoar-frostupongrassandvegetablesmuch thicker than that upon loftytrees?
Q.Why is thehoar-frostupongrassandvegetablesmuch thicker than that upon loftytrees?
A. Because the air (resting on thesurface of the ground) is much colder after sun-set, than theair higher up;in consequence of which, more vapour is condensed and frozen there.
A. Because the air (resting on thesurface of the ground) is much colder after sun-set, than theair higher up;in consequence of which, more vapour is condensed and frozen there.
Q.Why is theair(resting on the surface of theearth) colder than that in thehigherregions?A. Because theearth radiates more heatthan theleaves of lofty trees; and, therefore,condenses and freezesthe vapour of the airmore rapidly.
Q.Why is theair(resting on the surface of theearth) colder than that in thehigherregions?
Q.Why is theair(resting on the surface of theearth) colder than that in thehigherregions?
A. Because theearth radiates more heatthan theleaves of lofty trees; and, therefore,condenses and freezesthe vapour of the airmore rapidly.
A. Because theearth radiates more heatthan theleaves of lofty trees; and, therefore,condenses and freezesthe vapour of the airmore rapidly.
Q.Why areevergreensoftenfrost-bitten, when lofty trees arenot?A. Evergreens do notrise far above the surface of the earth; and (as the aircontiguous to the earthis muchcolder than that in the higher regions) therefore, thelow evergreen is often frost-bitten, when the lofty tree is uninjured.
Q.Why areevergreensoftenfrost-bitten, when lofty trees arenot?
Q.Why areevergreensoftenfrost-bitten, when lofty trees arenot?
A. Evergreens do notrise far above the surface of the earth; and (as the aircontiguous to the earthis muchcolder than that in the higher regions) therefore, thelow evergreen is often frost-bitten, when the lofty tree is uninjured.
A. Evergreens do notrise far above the surface of the earth; and (as the aircontiguous to the earthis muchcolder than that in the higher regions) therefore, thelow evergreen is often frost-bitten, when the lofty tree is uninjured.
Q.Why aretomb-stonescovered withhoar-frost, long after it has melted from every object around?A.White is a very bad absorbent of solar heat; and, therefore, thewhite tomb-stoneremainstoo coldto thaw the frost congealed upon its surface.
Q.Why aretomb-stonescovered withhoar-frost, long after it has melted from every object around?
Q.Why aretomb-stonescovered withhoar-frost, long after it has melted from every object around?
A.White is a very bad absorbent of solar heat; and, therefore, thewhite tomb-stoneremainstoo coldto thaw the frost congealed upon its surface.
A.White is a very bad absorbent of solar heat; and, therefore, thewhite tomb-stoneremainstoo coldto thaw the frost congealed upon its surface.
Q.Why is there little orno hoar-frostundershrubsand shadowytrees?A. 1st—Because the leafy shrubsand treesarrest the process of radiationfrom the earth: and2ndly—Shrubs and treesradiate a little heattowards the earth; and, therefore, theground beneathis nevercold enough to congeal the little dewwhich rests upon it.
Q.Why is there little orno hoar-frostundershrubsand shadowytrees?
Q.Why is there little orno hoar-frostundershrubsand shadowytrees?
A. 1st—Because the leafy shrubsand treesarrest the process of radiationfrom the earth: and2ndly—Shrubs and treesradiate a little heattowards the earth; and, therefore, theground beneathis nevercold enough to congeal the little dewwhich rests upon it.
A. 1st—Because the leafy shrubsand treesarrest the process of radiationfrom the earth: and
2ndly—Shrubs and treesradiate a little heattowards the earth; and, therefore, theground beneathis nevercold enough to congeal the little dewwhich rests upon it.
Q.What is the cause of thathoar-frostwhich arises fromfrozen fog?A. The thick fog (which invested the earth during the night) is condensedby the cold frostof early morning, andcongealed upon every objectwith which it comes in contact.
Q.What is the cause of thathoar-frostwhich arises fromfrozen fog?
Q.What is the cause of thathoar-frostwhich arises fromfrozen fog?
A. The thick fog (which invested the earth during the night) is condensedby the cold frostof early morning, andcongealed upon every objectwith which it comes in contact.
A. The thick fog (which invested the earth during the night) is condensedby the cold frostof early morning, andcongealed upon every objectwith which it comes in contact.
Q.What is meant by theconvectionofheat?A. Heat communicatedby being carriedto another thing or place; as the hot water resting on thebottomof akettle, carries heat to the waterthrough which it passes. (see p.246).
Q.What is meant by theconvectionofheat?
Q.What is meant by theconvectionofheat?
A. Heat communicatedby being carriedto another thing or place; as the hot water resting on thebottomof akettle, carries heat to the waterthrough which it passes. (see p.246).
A. Heat communicatedby being carriedto another thing or place; as the hot water resting on thebottomof akettle, carries heat to the waterthrough which it passes. (see p.246).
Q.Areliquidsgoodconductorsof heat?A. No; liquids arebad conductors; and are, therefore, made hot byconvection.
Q.Areliquidsgoodconductorsof heat?
Q.Areliquidsgoodconductorsof heat?
A. No; liquids arebad conductors; and are, therefore, made hot byconvection.
A. No; liquids arebad conductors; and are, therefore, made hot byconvection.
Q.Why areliquids bad conductorsof heat?A. Because heatconverts a liquid into steam, and flies off with the vapour, instead of beingconducted through the liquid.
Q.Why areliquids bad conductorsof heat?
Q.Why areliquids bad conductorsof heat?
A. Because heatconverts a liquid into steam, and flies off with the vapour, instead of beingconducted through the liquid.
A. Because heatconverts a liquid into steam, and flies off with the vapour, instead of beingconducted through the liquid.
Q.Explain howwateris madehot?A. The waternearest the fire is first heated, and (being heated)rises to the top;other cold water succeeds, isalsoheated, and rises in turn; and this interchange keeps going on,till all the water boils.
Q.Explain howwateris madehot?
Q.Explain howwateris madehot?
A. The waternearest the fire is first heated, and (being heated)rises to the top;other cold water succeeds, isalsoheated, and rises in turn; and this interchange keeps going on,till all the water boils.
A. The waternearest the fire is first heated, and (being heated)rises to the top;other cold water succeeds, isalsoheated, and rises in turn; and this interchange keeps going on,till all the water boils.
Q.Why iswaterin such continualferment, when it isboiling?A. This commotion is mainly produced by theascending and descending currentsof hot and cold water.The escape ofairfrom the water contributes also to increase this agitation.
Q.Why iswaterin such continualferment, when it isboiling?
Q.Why iswaterin such continualferment, when it isboiling?
A. This commotion is mainly produced by theascending and descending currentsof hot and cold water.The escape ofairfrom the water contributes also to increase this agitation.
A. This commotion is mainly produced by theascending and descending currentsof hot and cold water.
The escape ofairfrom the water contributes also to increase this agitation.
Q.How do these two currentspasseach other?A. Thehot ascending currentpasses close by themetal sidesof the kettle; while thecold descending currentpassesdown the centre.
Q.How do these two currentspasseach other?
Q.How do these two currentspasseach other?
A. Thehot ascending currentpasses close by themetal sidesof the kettle; while thecold descending currentpassesdown the centre.
A. Thehot ascending currentpasses close by themetal sidesof the kettle; while thecold descending currentpassesdown the centre.
Q.Why doesboiling water bubble?A. The bubbles areportions of steam(formed at the bottom of the vessel) whichrise to the surface, and escape into the air.
Q.Why doesboiling water bubble?
Q.Why doesboiling water bubble?
A. The bubbles areportions of steam(formed at the bottom of the vessel) whichrise to the surface, and escape into the air.
A. The bubbles areportions of steam(formed at the bottom of the vessel) whichrise to the surface, and escape into the air.
Q.Why does akettle run over, when the waterboils?A. As the heat insinuates itself between the particles of water,it drives them asunder; and (as the particles of water aredriven apart from each other) thesamevessel will no longer hold the expanded water, and some runs over.
Q.Why does akettle run over, when the waterboils?
Q.Why does akettle run over, when the waterboils?
A. As the heat insinuates itself between the particles of water,it drives them asunder; and (as the particles of water aredriven apart from each other) thesamevessel will no longer hold the expanded water, and some runs over.
A. As the heat insinuates itself between the particles of water,it drives them asunder; and (as the particles of water aredriven apart from each other) thesamevessel will no longer hold the expanded water, and some runs over.
Q.Why does akettle sing, when it isabouttoboil?A. Water containsa great deal of air, which (being expanded by the heat of the fire) escapes by fitsthrough the spout of the kettle; which sings in the same way as a trumpet does, when a person blows in it.
Q.Why does akettle sing, when it isabouttoboil?
Q.Why does akettle sing, when it isabouttoboil?
A. Water containsa great deal of air, which (being expanded by the heat of the fire) escapes by fitsthrough the spout of the kettle; which sings in the same way as a trumpet does, when a person blows in it.
A. Water containsa great deal of air, which (being expanded by the heat of the fire) escapes by fitsthrough the spout of the kettle; which sings in the same way as a trumpet does, when a person blows in it.
Q.Why doeswater boil?A. Boiling is the effect of amore violent escape of airfrom the heated water; when, therefore, the air isnot permitted to escape, water willnever boil.
Q.Why doeswater boil?
Q.Why doeswater boil?
A. Boiling is the effect of amore violent escape of airfrom the heated water; when, therefore, the air isnot permitted to escape, water willnever boil.
A. Boiling is the effect of amore violent escape of airfrom the heated water; when, therefore, the air isnot permitted to escape, water willnever boil.
Q.Why isheatapplied to thebottom, and not to the top of akettle?A. Because the heated wateralways ascends to the surface, heating the water through which it passes: if, therefore, heat were applied to thetop of a vessel, the waterbelow the surfacewouldnever be heated.
Q.Why isheatapplied to thebottom, and not to the top of akettle?
Q.Why isheatapplied to thebottom, and not to the top of akettle?
A. Because the heated wateralways ascends to the surface, heating the water through which it passes: if, therefore, heat were applied to thetop of a vessel, the waterbelow the surfacewouldnever be heated.
A. Because the heated wateralways ascends to the surface, heating the water through which it passes: if, therefore, heat were applied to thetop of a vessel, the waterbelow the surfacewouldnever be heated.
Q.As the lower part of agrateis madered-hotby the fireabove, why would not thewaterboil, if fire were applied to thetop?A. Theironof a grate is anexcellent conductor; and, therefore, ifonepart be heated, the heat is conducted toevery other part: butwateris avery bad conductor, and will not diffuse heat in a similar way.
Q.As the lower part of agrateis madered-hotby the fireabove, why would not thewaterboil, if fire were applied to thetop?
Q.As the lower part of agrateis madered-hotby the fireabove, why would not thewaterboil, if fire were applied to thetop?
A. Theironof a grate is anexcellent conductor; and, therefore, ifonepart be heated, the heat is conducted toevery other part: butwateris avery bad conductor, and will not diffuse heat in a similar way.
A. Theironof a grate is anexcellent conductor; and, therefore, ifonepart be heated, the heat is conducted toevery other part: butwateris avery bad conductor, and will not diffuse heat in a similar way.
Q.How do you know thatwateris abad conductorof heat?A. When a blacksmith immerseshis red-hot iron in a tank of water, the water whichsurroundsthe red-hot iron is madeboiling hot, but the waterbelowthe surface remains quite cold.
Q.How do you know thatwateris abad conductorof heat?
Q.How do you know thatwateris abad conductorof heat?
A. When a blacksmith immerseshis red-hot iron in a tank of water, the water whichsurroundsthe red-hot iron is madeboiling hot, but the waterbelowthe surface remains quite cold.
A. When a blacksmith immerseshis red-hot iron in a tank of water, the water whichsurroundsthe red-hot iron is madeboiling hot, but the waterbelowthe surface remains quite cold.
Q.If you wish tocool liquids, where should the cold be applied?A. To thetop of the liquid; because thecoldportion will alwaysdescend, and allow the warmer parts to come in contact with the cooling substance.
Q.If you wish tocool liquids, where should the cold be applied?
Q.If you wish tocool liquids, where should the cold be applied?
A. To thetop of the liquid; because thecoldportion will alwaysdescend, and allow the warmer parts to come in contact with the cooling substance.
A. To thetop of the liquid; because thecoldportion will alwaysdescend, and allow the warmer parts to come in contact with the cooling substance.
Q.Doesboilingwater get hotter by beingkepton thefire?A. No; not if the steam be suffered to escape.
Q.Doesboilingwater get hotter by beingkepton thefire?
Q.Doesboilingwater get hotter by beingkepton thefire?
A. No; not if the steam be suffered to escape.
A. No; not if the steam be suffered to escape.
Q.Why does not boiling water gethotter, if the steam be suffered toescape?A. Becauseas fast as the water boils, it is converted intosteam; and the steamcarries awaythe additional heat, as fast as it is communicated.
Q.Why does not boiling water gethotter, if the steam be suffered toescape?
Q.Why does not boiling water gethotter, if the steam be suffered toescape?
A. Becauseas fast as the water boils, it is converted intosteam; and the steamcarries awaythe additional heat, as fast as it is communicated.
A. Becauseas fast as the water boils, it is converted intosteam; and the steamcarries awaythe additional heat, as fast as it is communicated.
Q.Issteamvisible orinvisible?A. Steam isinvisible; but when it comes in contact with the air (beingcondensed into small drops) it instantly becomes visible.
Q.Issteamvisible orinvisible?
Q.Issteamvisible orinvisible?
A. Steam isinvisible; but when it comes in contact with the air (beingcondensed into small drops) it instantly becomes visible.
A. Steam isinvisible; but when it comes in contact with the air (beingcondensed into small drops) it instantly becomes visible.
Q.How do you know thatsteamisinvisible?A. If you look at the spout of a boiling kettle, you will find that the steam (which issues from the spout) is always invisiblefor about half an inch; after which,it becomes visible.
Q.How do you know thatsteamisinvisible?
Q.How do you know thatsteamisinvisible?
A. If you look at the spout of a boiling kettle, you will find that the steam (which issues from the spout) is always invisiblefor about half an inch; after which,it becomes visible.
A. If you look at the spout of a boiling kettle, you will find that the steam (which issues from the spout) is always invisiblefor about half an inch; after which,it becomes visible.
Q.Why is the steaminvisiblefor onlyhalf an inch, and not either allinvisibleor allvisible?A. The air is not able to condense the steam as it first issues from the spout, but when itspreadsand comes in contact with a larger volume of air, theinvisible steamis readily condensed intovisible drops.
Q.Why is the steaminvisiblefor onlyhalf an inch, and not either allinvisibleor allvisible?
Q.Why is the steaminvisiblefor onlyhalf an inch, and not either allinvisibleor allvisible?
A. The air is not able to condense the steam as it first issues from the spout, but when itspreadsand comes in contact with a larger volume of air, theinvisible steamis readily condensed intovisible drops.
A. The air is not able to condense the steam as it first issues from the spout, but when itspreadsand comes in contact with a larger volume of air, theinvisible steamis readily condensed intovisible drops.
Q.Why is ourbreath visiblein winter-time?A. Becauseit is condensed by the cold airinto small drops, which are visible to the eye.
Q.Why is ourbreath visiblein winter-time?
Q.Why is ourbreath visiblein winter-time?
A. Becauseit is condensed by the cold airinto small drops, which are visible to the eye.
A. Becauseit is condensed by the cold airinto small drops, which are visible to the eye.
Q.Why dosteam-enginessometimesburst?A. Steam is veryelastic; and this elasticity increases in a greater proportion than the heat which produces it; unless, therefore, someventbe freely allowed, the steam heaves and swells, till it bursts the vessel which confined it.
Q.Why dosteam-enginessometimesburst?
Q.Why dosteam-enginessometimesburst?
A. Steam is veryelastic; and this elasticity increases in a greater proportion than the heat which produces it; unless, therefore, someventbe freely allowed, the steam heaves and swells, till it bursts the vessel which confined it.
A. Steam is veryelastic; and this elasticity increases in a greater proportion than the heat which produces it; unless, therefore, someventbe freely allowed, the steam heaves and swells, till it bursts the vessel which confined it.
Q.Whatbecomesof the steam, after it has been condensed?A. It isdissolved by the air, and forms a part of its invisible vapour.
Q.Whatbecomesof the steam, after it has been condensed?
Q.Whatbecomesof the steam, after it has been condensed?
A. It isdissolved by the air, and forms a part of its invisible vapour.
A. It isdissolved by the air, and forms a part of its invisible vapour.
Q.Isaira goodconductor?A. No;air is a very bad conductor, and is heated (like water)by convection.
Q.Isaira goodconductor?
Q.Isaira goodconductor?
A. No;air is a very bad conductor, and is heated (like water)by convection.
A. No;air is a very bad conductor, and is heated (like water)by convection.
Q.How is aroom warmedby astove?A. The airnearest the fireis made hotfirst;the cold air descends, is heated also, and rises in turn; and this goes on,till all the air of the room is warmed.
Q.How is aroom warmedby astove?
Q.How is aroom warmedby astove?
A. The airnearest the fireis made hotfirst;the cold air descends, is heated also, and rises in turn; and this goes on,till all the air of the room is warmed.
A. The airnearest the fireis made hotfirst;the cold air descends, is heated also, and rises in turn; and this goes on,till all the air of the room is warmed.
Q.Why arefiresplaced on thefloorof a room, and not towards theceiling?A. As heated air alwaysascends, if the fire were notnear the floor, the lower part of the air (which we want to be the warmest) would never be benefited by the fire at all.
Q.Why arefiresplaced on thefloorof a room, and not towards theceiling?
Q.Why arefiresplaced on thefloorof a room, and not towards theceiling?
A. As heated air alwaysascends, if the fire were notnear the floor, the lower part of the air (which we want to be the warmest) would never be benefited by the fire at all.
A. As heated air alwaysascends, if the fire were notnear the floor, the lower part of the air (which we want to be the warmest) would never be benefited by the fire at all.
Q.If you take apokerout of the fire, and hold thehot end downwards, why is thehandleso intenselyhot?A. Because the hot end of the pokerheats the air around it, and this hot air (in its ascent)scorches the poker, and thehand which holds it.
Q.If you take apokerout of the fire, and hold thehot end downwards, why is thehandleso intenselyhot?
Q.If you take apokerout of the fire, and hold thehot end downwards, why is thehandleso intenselyhot?
A. Because the hot end of the pokerheats the air around it, and this hot air (in its ascent)scorches the poker, and thehand which holds it.
A. Because the hot end of the pokerheats the air around it, and this hot air (in its ascent)scorches the poker, and thehand which holds it.
Q.How should ared-hot pokerbe carried so as not toburnour fingers?A. With the hot endupwards; because then the air (heated by the poker)would not pass over our handto scorch it.
Q.How should ared-hot pokerbe carried so as not toburnour fingers?
Q.How should ared-hot pokerbe carried so as not toburnour fingers?
A. With the hot endupwards; because then the air (heated by the poker)would not pass over our handto scorch it.
A. With the hot endupwards; because then the air (heated by the poker)would not pass over our handto scorch it.
Q.Why is apoker(resting on thefender)cold; but if it leans against thestove, intensely warm?A. The poker is anexcellent conductor; while, therefore, it rests against the hot stove, the heat of the stove isconducted into the poker; but when itrests on the fender, it does not come incontact with the hot stove.
Q.Why is apoker(resting on thefender)cold; but if it leans against thestove, intensely warm?
Q.Why is apoker(resting on thefender)cold; but if it leans against thestove, intensely warm?
A. The poker is anexcellent conductor; while, therefore, it rests against the hot stove, the heat of the stove isconducted into the poker; but when itrests on the fender, it does not come incontact with the hot stove.
A. The poker is anexcellent conductor; while, therefore, it rests against the hot stove, the heat of the stove isconducted into the poker; but when itrests on the fender, it does not come incontact with the hot stove.
Q.Why does it feel socold, when it rests on thefender?A. Not being so warm as our hand, itimbibes the heat from itwith suchrapidity, that our loss of heat ispalpable, and produces the sensation of coldness.
Q.Why does it feel socold, when it rests on thefender?
Q.Why does it feel socold, when it rests on thefender?
A. Not being so warm as our hand, itimbibes the heat from itwith suchrapidity, that our loss of heat ispalpable, and produces the sensation of coldness.
A. Not being so warm as our hand, itimbibes the heat from itwith suchrapidity, that our loss of heat ispalpable, and produces the sensation of coldness.
Q.Why areflues(which are carried through a church or room) alwaysblackenedwithblack lead?A. In order that the heat of the fluemay be more readily diffusedthroughout the room. Black lead radiates heat more freely than any other known substance.
Q.Why areflues(which are carried through a church or room) alwaysblackenedwithblack lead?
Q.Why areflues(which are carried through a church or room) alwaysblackenedwithblack lead?
A. In order that the heat of the fluemay be more readily diffusedthroughout the room. Black lead radiates heat more freely than any other known substance.
A. In order that the heat of the fluemay be more readily diffusedthroughout the room. Black lead radiates heat more freely than any other known substance.
Q.Why do country people touch the thick end of aneggwith theirtongue, to know if it bestaleor not?A. The thick end of an egg always containsa little air(between the shell and the white); but, when the egg is stale,the white shrinks, and the air expands.
Q.Why do country people touch the thick end of aneggwith theirtongue, to know if it bestaleor not?
Q.Why do country people touch the thick end of aneggwith theirtongue, to know if it bestaleor not?
A. The thick end of an egg always containsa little air(between the shell and the white); but, when the egg is stale,the white shrinks, and the air expands.
A. The thick end of an egg always containsa little air(between the shell and the white); but, when the egg is stale,the white shrinks, and the air expands.
Q.How can thetonguetell from this, whether the egg bestaleorfreshlaid?A. As air is avery bad conductor, if the egg bestale, it will feel muchwarmer to the tongue, than if it be new-laid.
Q.How can thetonguetell from this, whether the egg bestaleorfreshlaid?
Q.How can thetonguetell from this, whether the egg bestaleorfreshlaid?
A. As air is avery bad conductor, if the egg bestale, it will feel muchwarmer to the tongue, than if it be new-laid.
A. As air is avery bad conductor, if the egg bestale, it will feel muchwarmer to the tongue, than if it be new-laid.
Q.Why will the big end of an egg feelwarmerto the tongue, because it contains moreair?A. As air is abad conductor, it will draw off the heat of the tonguevery slowly, and, therefore,appear warm; but when there is only avery little air in the egg(as thewhiteis a pretty good conductor), the heat of the tongue will bemore rapidlydrawn off, and the eggappear colder.
Q.Why will the big end of an egg feelwarmerto the tongue, because it contains moreair?
Q.Why will the big end of an egg feelwarmerto the tongue, because it contains moreair?
A. As air is abad conductor, it will draw off the heat of the tonguevery slowly, and, therefore,appear warm; but when there is only avery little air in the egg(as thewhiteis a pretty good conductor), the heat of the tongue will bemore rapidlydrawn off, and the eggappear colder.
A. As air is abad conductor, it will draw off the heat of the tonguevery slowly, and, therefore,appear warm; but when there is only avery little air in the egg(as thewhiteis a pretty good conductor), the heat of the tongue will bemore rapidlydrawn off, and the eggappear colder.
Q.Why is the largeendof anegg cracked, when put into a saucepan to boil?A.To let the air out; if the large end werenot cracked, the air (expanded by the heat)would enter the white of the egg, and give it anoffensive taste.
Q.Why is the largeendof anegg cracked, when put into a saucepan to boil?
Q.Why is the largeendof anegg cracked, when put into a saucepan to boil?
A.To let the air out; if the large end werenot cracked, the air (expanded by the heat)would enter the white of the egg, and give it anoffensive taste.
A.To let the air out; if the large end werenot cracked, the air (expanded by the heat)would enter the white of the egg, and give it anoffensive taste.
Q.Of what is atmosphericaircomposed?A. Principally of two gases,oxygenandnitrogen; mixed together in the following proportion: viz. 1 part of oxygen, to 4 parts of nitrogen.
Q.Of what is atmosphericaircomposed?
Q.Of what is atmosphericaircomposed?
A. Principally of two gases,oxygenandnitrogen; mixed together in the following proportion: viz. 1 part of oxygen, to 4 parts of nitrogen.
A. Principally of two gases,oxygenandnitrogen; mixed together in the following proportion: viz. 1 part of oxygen, to 4 parts of nitrogen.
Q.What are the uses of theoxygenof the air?A. It is theoxygenof the air whichsupports combustion, andsustains life.
Q.What are the uses of theoxygenof the air?
Q.What are the uses of theoxygenof the air?
A. It is theoxygenof the air whichsupports combustion, andsustains life.
A. It is theoxygenof the air whichsupports combustion, andsustains life.
Q.What is meant when it is said, that theoxygenof the air “supports combustion?”A. It means this; that it is theoxygen of the airwhich makesfuel burn.
Q.What is meant when it is said, that theoxygenof the air “supports combustion?”
Q.What is meant when it is said, that theoxygenof the air “supports combustion?”
A. It means this; that it is theoxygen of the airwhich makesfuel burn.
A. It means this; that it is theoxygen of the airwhich makesfuel burn.
Q.How does theoxygenof the air makefuel burn?A. The fuel being decomposed (by heat) intohydrogenandcarbon; thecarbon combines with the oxygen of the air, and producescombustion.
Q.How does theoxygenof the air makefuel burn?
Q.How does theoxygenof the air makefuel burn?
A. The fuel being decomposed (by heat) intohydrogenandcarbon; thecarbon combines with the oxygen of the air, and producescombustion.
A. The fuel being decomposed (by heat) intohydrogenandcarbon; thecarbon combines with the oxygen of the air, and producescombustion.
Q.What does the combination of carbon and oxygen produce?A. Thecarbon of the fuelcombining with theoxygen of the airmakescarbonic acid gas. (see pp.36,37).
Q.What does the combination of carbon and oxygen produce?
Q.What does the combination of carbon and oxygen produce?
A. Thecarbon of the fuelcombining with theoxygen of the airmakescarbonic acid gas. (see pp.36,37).
A. Thecarbon of the fuelcombining with theoxygen of the airmakescarbonic acid gas. (see pp.36,37).
Q.What becomes of thehydrogenof thefuel?A. Hydrogen (being very inflammable)burns with a blaze, and is the cause of theflamewhich is produced by combustion. (see p.34).
Q.What becomes of thehydrogenof thefuel?
Q.What becomes of thehydrogenof thefuel?
A. Hydrogen (being very inflammable)burns with a blaze, and is the cause of theflamewhich is produced by combustion. (see p.34).
A. Hydrogen (being very inflammable)burns with a blaze, and is the cause of theflamewhich is produced by combustion. (see p.34).
Q.What becomes of thenitrogenof the air, amidst all these changes and combinations?A. Thenitrogen of the air escapes, and isabsorbed by the leavesof grass, trees, and various other vegetables.
Q.What becomes of thenitrogenof the air, amidst all these changes and combinations?
Q.What becomes of thenitrogenof the air, amidst all these changes and combinations?
A. Thenitrogen of the air escapes, and isabsorbed by the leavesof grass, trees, and various other vegetables.
A. Thenitrogen of the air escapes, and isabsorbed by the leavesof grass, trees, and various other vegetables.
Q.What is meant when it is said, thatoxygen “sustains life”?A. It means this: if a personcould not inhale oxygen, he woulddie.
Q.What is meant when it is said, thatoxygen “sustains life”?
Q.What is meant when it is said, thatoxygen “sustains life”?
A. It means this: if a personcould not inhale oxygen, he woulddie.
A. It means this: if a personcould not inhale oxygen, he woulddie.
Q.Whatgooddoes this inspiration ofoxygendo?A. 1st—It givesvitality to the blood: and2ndly—It is thecause of animal heat.
Q.Whatgooddoes this inspiration ofoxygendo?
Q.Whatgooddoes this inspiration ofoxygendo?
A. 1st—It givesvitality to the blood: and2ndly—It is thecause of animal heat.
A. 1st—It givesvitality to the blood: and
2ndly—It is thecause of animal heat.
Q.How isfoodconverted intoblood?A. After it is swallowed, it is dissolved in the stomach into agrey pulp; it then passes into the intestines, and is converted by the “bile”into a milky substance(calledchyle).
Q.How isfoodconverted intoblood?
Q.How isfoodconverted intoblood?
A. After it is swallowed, it is dissolved in the stomach into agrey pulp; it then passes into the intestines, and is converted by the “bile”into a milky substance(calledchyle).
A. After it is swallowed, it is dissolved in the stomach into agrey pulp; it then passes into the intestines, and is converted by the “bile”into a milky substance(calledchyle).
Q.Whatbecomesof the milky substance, calledchyle?A. It is absorbed by the vessels called “lacteals,” and poured into the veinson the left side of the neck.
Q.Whatbecomesof the milky substance, calledchyle?
Q.Whatbecomesof the milky substance, calledchyle?
A. It is absorbed by the vessels called “lacteals,” and poured into the veinson the left side of the neck.
A. It is absorbed by the vessels called “lacteals,” and poured into the veinson the left side of the neck.
Q.What becomes of the chyleafterit ispouredinto theveins?A. It thenmingles with the blood, and is itselfconverted into blood.
Q.What becomes of the chyleafterit ispouredinto theveins?
Q.What becomes of the chyleafterit ispouredinto theveins?
A. It thenmingles with the blood, and is itselfconverted into blood.
A. It thenmingles with the blood, and is itselfconverted into blood.
Q.How does theoxygenwe inhaleminglewith theblood?A. The oxygen of the air mingles with the bloodin the lungs, and converts it into abright red colour.
Q.How does theoxygenwe inhaleminglewith theblood?
Q.How does theoxygenwe inhaleminglewith theblood?
A. The oxygen of the air mingles with the bloodin the lungs, and converts it into abright red colour.
A. The oxygen of the air mingles with the bloodin the lungs, and converts it into abright red colour.
Q.What colour is the bloodbeforeit is oxydized in the lungs?A.A dark purple.The oxygen turns it toa bright red.
Q.What colour is the bloodbeforeit is oxydized in the lungs?
Q.What colour is the bloodbeforeit is oxydized in the lungs?
A.A dark purple.The oxygen turns it toa bright red.
A.A dark purple.The oxygen turns it toa bright red.
Q.Why arepersonssopalewho live inclose roomsandcities?A. The blood derives its redness from theoxygenof the air inhaled; but, as the air in close rooms and citiesis not fresh, it isdeficient in oxygen, and cannot turn the blood to a beautiful bright red.
Q.Why arepersonssopalewho live inclose roomsandcities?
Q.Why arepersonssopalewho live inclose roomsandcities?
A. The blood derives its redness from theoxygenof the air inhaled; but, as the air in close rooms and citiesis not fresh, it isdeficient in oxygen, and cannot turn the blood to a beautiful bright red.
A. The blood derives its redness from theoxygenof the air inhaled; but, as the air in close rooms and citiesis not fresh, it isdeficient in oxygen, and cannot turn the blood to a beautiful bright red.
Q.Why arepersonswho live in theopen airand in the country, of aruddycomplexion?A. As the blood derives its bright red colour from theoxygenof the air inhaled, therefore, country-people (who inhalefresh air) are more ruddy than citizens.
Q.Why arepersonswho live in theopen airand in the country, of aruddycomplexion?
Q.Why arepersonswho live in theopen airand in the country, of aruddycomplexion?
A. As the blood derives its bright red colour from theoxygenof the air inhaled, therefore, country-people (who inhalefresh air) are more ruddy than citizens.
A. As the blood derives its bright red colour from theoxygenof the air inhaled, therefore, country-people (who inhalefresh air) are more ruddy than citizens.
Q.Why is not the air incitiessofreshas that in thecountry?A. Because it is impregnated with thebreath of its numerous inhabitants, theodour of its sewers, thesmoke of its fires, and many other impurities.
Q.Why is not the air incitiessofreshas that in thecountry?
Q.Why is not the air incitiessofreshas that in thecountry?
A. Because it is impregnated with thebreath of its numerous inhabitants, theodour of its sewers, thesmoke of its fires, and many other impurities.
A. Because it is impregnated with thebreath of its numerous inhabitants, theodour of its sewers, thesmoke of its fires, and many other impurities.
Q.How does thecombinationofoxygenwith thebloodproduce animalheat?A. The principal element of the blood iscarbon, which (combining with the oxygen of the air inhaled) producescarbonic acid gas, (in the same way as burning fuel.) (see pp.33,36).
Q.How does thecombinationofoxygenwith thebloodproduce animalheat?
Q.How does thecombinationofoxygenwith thebloodproduce animalheat?
A. The principal element of the blood iscarbon, which (combining with the oxygen of the air inhaled) producescarbonic acid gas, (in the same way as burning fuel.) (see pp.33,36).
A. The principal element of the blood iscarbon, which (combining with the oxygen of the air inhaled) producescarbonic acid gas, (in the same way as burning fuel.) (see pp.33,36).
Q.What becomes of thenitrogenof the air, after the oxygen enters the blood?A. The nitrogen isexhaled, and taken up by the leaves of trees and other vegetables. (see p.35).
Q.What becomes of thenitrogenof the air, after the oxygen enters the blood?
Q.What becomes of thenitrogenof the air, after the oxygen enters the blood?
A. The nitrogen isexhaled, and taken up by the leaves of trees and other vegetables. (see p.35).
A. The nitrogen isexhaled, and taken up by the leaves of trees and other vegetables. (see p.35).
Q.Why does the vitiated air (after the oxygen has been absorbed)come outof themouth, and not sink into the stomach?A. The vitiated air (beingheated by the heat of the body)ascends naturally, and passes by theheavier fresh air(which we inhale) without obstruction or injury.
Q.Why does the vitiated air (after the oxygen has been absorbed)come outof themouth, and not sink into the stomach?
Q.Why does the vitiated air (after the oxygen has been absorbed)come outof themouth, and not sink into the stomach?
A. The vitiated air (beingheated by the heat of the body)ascends naturally, and passes by theheavier fresh air(which we inhale) without obstruction or injury.
A. The vitiated air (beingheated by the heat of the body)ascends naturally, and passes by theheavier fresh air(which we inhale) without obstruction or injury.
Q.If (both in combustion and in respiration) theoxygenof the air isconsumed, and thenitrogen rejected—Why are not theproportionsof theair destroyed?A. Because theupper surface of vegetable leaves(during the day)gives out oxygenandabsorbs nitrogen, and thus the proper balance is perpetually restored.
Q.If (both in combustion and in respiration) theoxygenof the air isconsumed, and thenitrogen rejected—Why are not theproportionsof theair destroyed?
Q.If (both in combustion and in respiration) theoxygenof the air isconsumed, and thenitrogen rejected—Why are not theproportionsof theair destroyed?
A. Because theupper surface of vegetable leaves(during the day)gives out oxygenandabsorbs nitrogen, and thus the proper balance is perpetually restored.
A. Because theupper surface of vegetable leaves(during the day)gives out oxygenandabsorbs nitrogen, and thus the proper balance is perpetually restored.
Q.Show how God has madeanimalandvegetablelifedependenton each other?A.Animalsrequireoxygento keep them alive, anddraw it from the airby inspiration; the upper surface ofleaves(all day long)gives out oxygen, and thus supplies the air with thevery gasrequired by man and other animals.
Q.Show how God has madeanimalandvegetablelifedependenton each other?
Q.Show how God has madeanimalandvegetablelifedependenton each other?
A.Animalsrequireoxygento keep them alive, anddraw it from the airby inspiration; the upper surface ofleaves(all day long)gives out oxygen, and thus supplies the air with thevery gasrequired by man and other animals.
A.Animalsrequireoxygento keep them alive, anddraw it from the airby inspiration; the upper surface ofleaves(all day long)gives out oxygen, and thus supplies the air with thevery gasrequired by man and other animals.
Q.Do not animalsexhalethevery gasneeded byvegetables?A. Yes; animals reject thenitrogen of the air(as not suited to the use of animal life), butvegetables absorb it, as it is the food they live on; and thus the vegetable world restores the equilibrium of the air, disturbed by man and other animals.
Q.Do not animalsexhalethevery gasneeded byvegetables?
Q.Do not animalsexhalethevery gasneeded byvegetables?
A. Yes; animals reject thenitrogen of the air(as not suited to the use of animal life), butvegetables absorb it, as it is the food they live on; and thus the vegetable world restores the equilibrium of the air, disturbed by man and other animals.
A. Yes; animals reject thenitrogen of the air(as not suited to the use of animal life), butvegetables absorb it, as it is the food they live on; and thus the vegetable world restores the equilibrium of the air, disturbed by man and other animals.
Q.Isaira goodconductor?A. No; air is a verybad conductor.
Q.Isaira goodconductor?
Q.Isaira goodconductor?
A. No; air is a verybad conductor.
A. No; air is a verybad conductor.
Q.How isair heated?A. By “convective currents.”
Q.How isair heated?
Q.How isair heated?
A. By “convective currents.”
A. By “convective currents.”
Q.What are meant by “convective currents?”A. When a portion of air is heated,it rises upward in a current, carrying the heat with it: othercolder air succeeds, and (beingheatedin a similar way)ascends also; and these are called convective currents.(“Convective currents;” so called from the Latin words, cum-vectus (carried with) because theheatis “carried with” the current.)
Q.What are meant by “convective currents?”
Q.What are meant by “convective currents?”
A. When a portion of air is heated,it rises upward in a current, carrying the heat with it: othercolder air succeeds, and (beingheatedin a similar way)ascends also; and these are called convective currents.(“Convective currents;” so called from the Latin words, cum-vectus (carried with) because theheatis “carried with” the current.)
A. When a portion of air is heated,it rises upward in a current, carrying the heat with it: othercolder air succeeds, and (beingheatedin a similar way)ascends also; and these are called convective currents.
(“Convective currents;” so called from the Latin words, cum-vectus (carried with) because theheatis “carried with” the current.)
Q.Isair heatedby theraysof thesun?A. No; air isnot heated(in any sensible degree)by the action of the sun’s rayspassing through it.
Q.Isair heatedby theraysof thesun?
Q.Isair heatedby theraysof thesun?
A. No; air isnot heated(in any sensible degree)by the action of the sun’s rayspassing through it.
A. No; air isnot heated(in any sensible degree)by the action of the sun’s rayspassing through it.
Q.Why then is theair hotteron asunny day, than on acloudyone?A. On a fine day, the sunheats the surface of the earth, and the air (resting on the earth)is heated by contact; as soon as it is heatedit ascends, andotherair succeeding isheated in a similar way, till all is heated by convection.
Q.Why then is theair hotteron asunny day, than on acloudyone?
Q.Why then is theair hotteron asunny day, than on acloudyone?
A. On a fine day, the sunheats the surface of the earth, and the air (resting on the earth)is heated by contact; as soon as it is heatedit ascends, andotherair succeeding isheated in a similar way, till all is heated by convection.
A. On a fine day, the sunheats the surface of the earth, and the air (resting on the earth)is heated by contact; as soon as it is heatedit ascends, andotherair succeeding isheated in a similar way, till all is heated by convection.
Q.Ifairbe abad conductor, why does hotirongetcold, by beingexposedto theair?A. A piece of hot iron exposed to the air, is made cold—1st—By “convection;” and2ndly—By “radiation.”
Q.Ifairbe abad conductor, why does hotirongetcold, by beingexposedto theair?
Q.Ifairbe abad conductor, why does hotirongetcold, by beingexposedto theair?
A. A piece of hot iron exposed to the air, is made cold—1st—By “convection;” and2ndly—By “radiation.”
A. A piece of hot iron exposed to the air, is made cold—1st—By “convection;” and
2ndly—By “radiation.”
Q.How is hot iron (exposed to the air) made cold byconvection?A. The air around the iron (being intensely heated by contact) rapidly ascends,carrying some of its heat with it:other air succeeds,absorbs more heat, ascends, and gives place to that which iscolder; till the hot ironis cooled completely down.
Q.How is hot iron (exposed to the air) made cold byconvection?
Q.How is hot iron (exposed to the air) made cold byconvection?
A. The air around the iron (being intensely heated by contact) rapidly ascends,carrying some of its heat with it:other air succeeds,absorbs more heat, ascends, and gives place to that which iscolder; till the hot ironis cooled completely down.
A. The air around the iron (being intensely heated by contact) rapidly ascends,carrying some of its heat with it:other air succeeds,absorbs more heat, ascends, and gives place to that which iscolder; till the hot ironis cooled completely down.
Q.How is hot iron cooled byradiation?A. While the heat of the iron is being carried off by “convection,” it isthrowing off heat(on all sides)by radiation.
Q.How is hot iron cooled byradiation?
Q.How is hot iron cooled byradiation?
A. While the heat of the iron is being carried off by “convection,” it isthrowing off heat(on all sides)by radiation.
A. While the heat of the iron is being carried off by “convection,” it isthrowing off heat(on all sides)by radiation.
Q.What is meant byradiation?A. Heat emitted (in all directions) from any surface, byinnumerable rays.
Q.What is meant byradiation?
Q.What is meant byradiation?
A. Heat emitted (in all directions) from any surface, byinnumerable rays.
A. Heat emitted (in all directions) from any surface, byinnumerable rays.
Q.Why isbroth cooledby being left exposed to theair?A. Hot broth throws offsomeheat byradiation; but it ismainlycooled downby convection.
Q.Why isbroth cooledby being left exposed to theair?
Q.Why isbroth cooledby being left exposed to theair?
A. Hot broth throws offsomeheat byradiation; but it ismainlycooled downby convection.
A. Hot broth throws offsomeheat byradiation; but it ismainlycooled downby convection.
Q.How is hotbrothcooled down byconvection?A. The airresting on the hot broth(being heated)ascends;colderair succeedingabsorbs more heat, andascends also; and this process is repeated, till the broth ismade cool.
Q.How is hotbrothcooled down byconvection?
Q.How is hotbrothcooled down byconvection?
A. The airresting on the hot broth(being heated)ascends;colderair succeedingabsorbs more heat, andascends also; and this process is repeated, till the broth ismade cool.
A. The airresting on the hot broth(being heated)ascends;colderair succeedingabsorbs more heat, andascends also; and this process is repeated, till the broth ismade cool.
Q.Why is hotteaandbroth cooledfaster, for beingstirredabout?A. 1st—The agitation assists the liquor inbringing its hottest particles to the surface:2ndly—The action of stirringagitates the air, and brings itquickerto the broth or tea: and3rdly—As the hottest particles are more rapidly brought into contact with the air, thereforeconvection is more rapid.
Q.Why is hotteaandbroth cooledfaster, for beingstirredabout?
Q.Why is hotteaandbroth cooledfaster, for beingstirredabout?
A. 1st—The agitation assists the liquor inbringing its hottest particles to the surface:2ndly—The action of stirringagitates the air, and brings itquickerto the broth or tea: and3rdly—As the hottest particles are more rapidly brought into contact with the air, thereforeconvection is more rapid.
A. 1st—The agitation assists the liquor inbringing its hottest particles to the surface:
2ndly—The action of stirringagitates the air, and brings itquickerto the broth or tea: and
3rdly—As the hottest particles are more rapidly brought into contact with the air, thereforeconvection is more rapid.
Q.Why ishot tea, &c. cooled more rapidly byblowingit?A. Because the heated air isblown more rapidly away; in consequence of which,cold air more rapidly succeedstoabsorb heatfrom the surface of the tea or broth.
Q.Why ishot tea, &c. cooled more rapidly byblowingit?
Q.Why ishot tea, &c. cooled more rapidly byblowingit?
A. Because the heated air isblown more rapidly away; in consequence of which,cold air more rapidly succeedstoabsorb heatfrom the surface of the tea or broth.
A. Because the heated air isblown more rapidly away; in consequence of which,cold air more rapidly succeedstoabsorb heatfrom the surface of the tea or broth.
Q.If a shutter be closed in the day-time, the stream of light (piercing through the crevice) seems inconstant agitation.Whyis this?A. The air (in the sun-beam piercing through the shutter-crevice) ismore heated, thanthat in its neighbourhood; the convective current, therefore, isdistinctly seen, where little motes and particles of dust arethrown into agitationby theviolenceof the current.
Q.If a shutter be closed in the day-time, the stream of light (piercing through the crevice) seems inconstant agitation.Whyis this?
Q.If a shutter be closed in the day-time, the stream of light (piercing through the crevice) seems inconstant agitation.Whyis this?
A. The air (in the sun-beam piercing through the shutter-crevice) ismore heated, thanthat in its neighbourhood; the convective current, therefore, isdistinctly seen, where little motes and particles of dust arethrown into agitationby theviolenceof the current.
A. The air (in the sun-beam piercing through the shutter-crevice) ismore heated, thanthat in its neighbourhood; the convective current, therefore, isdistinctly seen, where little motes and particles of dust arethrown into agitationby theviolenceof the current.
Q.Why is thegalleryof achurchor theatrehotterthan theaisleor pit?A. The hot air ascends from thebottomto thetop of the room, and cold air (from the doors and windows) flies to thebottomto supply its place.
Q.Why is thegalleryof achurchor theatrehotterthan theaisleor pit?
Q.Why is thegalleryof achurchor theatrehotterthan theaisleor pit?
A. The hot air ascends from thebottomto thetop of the room, and cold air (from the doors and windows) flies to thebottomto supply its place.
A. The hot air ascends from thebottomto thetop of the room, and cold air (from the doors and windows) flies to thebottomto supply its place.
Q.Why does acrowded roomproducehead-ache?A. Because we breathe airvitiated by the crowd.
Q.Why does acrowded roomproducehead-ache?
Q.Why does acrowded roomproducehead-ache?
A. Because we breathe airvitiated by the crowd.
A. Because we breathe airvitiated by the crowd.
Q.How does acrowd vitiatetheairof aroom?A. Whenever we breathe, the elements of the air areseparatedin the lungs,some of the oxygen is absorbed by the blood, and some of it is converted intocarbonic acid gas, and exhaled with the nitrogen.
Q.How does acrowd vitiatetheairof aroom?
Q.How does acrowd vitiatetheairof aroom?
A. Whenever we breathe, the elements of the air areseparatedin the lungs,some of the oxygen is absorbed by the blood, and some of it is converted intocarbonic acid gas, and exhaled with the nitrogen.
A. Whenever we breathe, the elements of the air areseparatedin the lungs,some of the oxygen is absorbed by the blood, and some of it is converted intocarbonic acid gas, and exhaled with the nitrogen.
Q.Isallthenitrogen rejectedby the lungs?A. Yes; all the nitrogen of the air is always exhaled.
Q.Isallthenitrogen rejectedby the lungs?
Q.Isallthenitrogen rejectedby the lungs?
A. Yes; all the nitrogen of the air is always exhaled.
A. Yes; all the nitrogen of the air is always exhaled.
Q.What iscarbonic acid gas?A. As carbon has a very great affinity for oxygen, therefore, whenever they are exposed to heat, theycombine,and form carbonic acid gas (or what is vulgarly called fixed air).
Q.What iscarbonic acid gas?
Q.What iscarbonic acid gas?
A. As carbon has a very great affinity for oxygen, therefore, whenever they are exposed to heat, theycombine,and form carbonic acid gas (or what is vulgarly called fixed air).
A. As carbon has a very great affinity for oxygen, therefore, whenever they are exposed to heat, theycombine,and form carbonic acid gas (or what is vulgarly called fixed air).
Q.Iscarbonic acid gaswholesome?A. No; it is quitefatal to animal life; and whenever it is inhaled, it acts like a narcotic poison, (producing drowsiness which ends in death).
Q.Iscarbonic acid gaswholesome?
Q.Iscarbonic acid gaswholesome?
A. No; it is quitefatal to animal life; and whenever it is inhaled, it acts like a narcotic poison, (producing drowsiness which ends in death).
A. No; it is quitefatal to animal life; and whenever it is inhaled, it acts like a narcotic poison, (producing drowsiness which ends in death).
Q.Why is acrowded room unwholesome?A. Because the oxygen of the air is eitherabsorbed by the lungs, or substituted forcarbonic acid gas, which is a noxious poison.
Q.Why is acrowded room unwholesome?
Q.Why is acrowded room unwholesome?
A. Because the oxygen of the air is eitherabsorbed by the lungs, or substituted forcarbonic acid gas, which is a noxious poison.
A. Because the oxygen of the air is eitherabsorbed by the lungs, or substituted forcarbonic acid gas, which is a noxious poison.
Q.Mention the historical circumstances, so well known in connection with the “Black HoleofCalcutta.”A. In the reign of George II, the Raja (or Prince) of Bengal[12]marched suddenly to Calcutta to drive the English from the country; as the attack was unexpected, the English were obliged to submit, and 146 persons were taken prisoners.[12]The Sur Raja, at Dowlat; a young man of violent passions, who had but just succeeded to the throne. A. D. 1756.
Q.Mention the historical circumstances, so well known in connection with the “Black HoleofCalcutta.”
Q.Mention the historical circumstances, so well known in connection with the “Black HoleofCalcutta.”
A. In the reign of George II, the Raja (or Prince) of Bengal[12]marched suddenly to Calcutta to drive the English from the country; as the attack was unexpected, the English were obliged to submit, and 146 persons were taken prisoners.[12]The Sur Raja, at Dowlat; a young man of violent passions, who had but just succeeded to the throne. A. D. 1756.
A. In the reign of George II, the Raja (or Prince) of Bengal[12]marched suddenly to Calcutta to drive the English from the country; as the attack was unexpected, the English were obliged to submit, and 146 persons were taken prisoners.
[12]The Sur Raja, at Dowlat; a young man of violent passions, who had but just succeeded to the throne. A. D. 1756.
[12]The Sur Raja, at Dowlat; a young man of violent passions, who had but just succeeded to the throne. A. D. 1756.
Q.What became of these prisoners?A. They were driven into a place about 18 feet square, and 15 or 16 feet in height, with only two small grated windows. 123 of the prisoners died in one night; and (of the 23 who survived) the larger portion died of putrid fevers, after they were liberated in the morning.
Q.What became of these prisoners?
Q.What became of these prisoners?
A. They were driven into a place about 18 feet square, and 15 or 16 feet in height, with only two small grated windows. 123 of the prisoners died in one night; and (of the 23 who survived) the larger portion died of putrid fevers, after they were liberated in the morning.
A. They were driven into a place about 18 feet square, and 15 or 16 feet in height, with only two small grated windows. 123 of the prisoners died in one night; and (of the 23 who survived) the larger portion died of putrid fevers, after they were liberated in the morning.
Q.Why were 123 personssuffocatedin a few hours, from confinement in this close hotprison-hole?A. Because theoxygen of the airwas soon consumed by so many lungs, and its place supplied bycarbonic acidexhaled by the hot breath.
Q.Why were 123 personssuffocatedin a few hours, from confinement in this close hotprison-hole?
Q.Why were 123 personssuffocatedin a few hours, from confinement in this close hotprison-hole?
A. Because theoxygen of the airwas soon consumed by so many lungs, and its place supplied bycarbonic acidexhaled by the hot breath.
A. Because theoxygen of the airwas soon consumed by so many lungs, and its place supplied bycarbonic acidexhaled by the hot breath.
Q.Why do persons in a crowdedchurchfeeldrowsy?A. 1st—Because the crowded congregationinhale a large portion of the oxygen of the air, which alone can sustain vitality and healthy action: and2ndly—The air of the church is impregnated with carbonic acid gas, which (being a strong narcotic) produces drowsiness in those who inhale it.
Q.Why do persons in a crowdedchurchfeeldrowsy?
Q.Why do persons in a crowdedchurchfeeldrowsy?
A. 1st—Because the crowded congregationinhale a large portion of the oxygen of the air, which alone can sustain vitality and healthy action: and2ndly—The air of the church is impregnated with carbonic acid gas, which (being a strong narcotic) produces drowsiness in those who inhale it.
A. 1st—Because the crowded congregationinhale a large portion of the oxygen of the air, which alone can sustain vitality and healthy action: and
2ndly—The air of the church is impregnated with carbonic acid gas, which (being a strong narcotic) produces drowsiness in those who inhale it.
Q.Why did the captives in theblack holediesleeping?A. 1st—Because theabsence of oxygenquickly affects the vital functions, depresses the nervous energies, and produces a lassitude which ends in death: and2ndly—Thecarbonic acid gasinhaled by the captives (being a narcotic poison) would also producedrowsiness and death.
Q.Why did the captives in theblack holediesleeping?
Q.Why did the captives in theblack holediesleeping?
A. 1st—Because theabsence of oxygenquickly affects the vital functions, depresses the nervous energies, and produces a lassitude which ends in death: and2ndly—Thecarbonic acid gasinhaled by the captives (being a narcotic poison) would also producedrowsiness and death.
A. 1st—Because theabsence of oxygenquickly affects the vital functions, depresses the nervous energies, and produces a lassitude which ends in death: and
2ndly—Thecarbonic acid gasinhaled by the captives (being a narcotic poison) would also producedrowsiness and death.
Q.Why dopersons, who are so much in theopen air, enjoy the besthealth?A. Because the air they inhale ismuch more pure.
Q.Why dopersons, who are so much in theopen air, enjoy the besthealth?
Q.Why dopersons, who are so much in theopen air, enjoy the besthealth?
A. Because the air they inhale ismuch more pure.
A. Because the air they inhale ismuch more pure.
Q.Why iscountry airmorepurethan the air incities?A. 1st—Because there are fewer inhabitants to vitiate the air:2ndly—There are more trees to restore the equilibrium of the vitiated air: and3rdly—The free circulation of air keeps it pure and wholesome (in the same way as running streams are pure and wholesome, while stagnant waters are the contrary).
Q.Why iscountry airmorepurethan the air incities?
Q.Why iscountry airmorepurethan the air incities?
A. 1st—Because there are fewer inhabitants to vitiate the air:2ndly—There are more trees to restore the equilibrium of the vitiated air: and3rdly—The free circulation of air keeps it pure and wholesome (in the same way as running streams are pure and wholesome, while stagnant waters are the contrary).
A. 1st—Because there are fewer inhabitants to vitiate the air:
2ndly—There are more trees to restore the equilibrium of the vitiated air: and
3rdly—The free circulation of air keeps it pure and wholesome (in the same way as running streams are pure and wholesome, while stagnant waters are the contrary).
Q.Why does thescantinessof a countrypopulationrender thecountry airmorepure?A. Because the fewer the inhabitants,the less carbonic acid will be exhaled; and thus country people will inhalepure oxygen, instead of airimpregnated with the narcotic poison, called carbonic acid gas.
Q.Why does thescantinessof a countrypopulationrender thecountry airmorepure?
Q.Why does thescantinessof a countrypopulationrender thecountry airmorepure?
A. Because the fewer the inhabitants,the less carbonic acid will be exhaled; and thus country people will inhalepure oxygen, instead of airimpregnated with the narcotic poison, called carbonic acid gas.
A. Because the fewer the inhabitants,the less carbonic acid will be exhaled; and thus country people will inhalepure oxygen, instead of airimpregnated with the narcotic poison, called carbonic acid gas.