Q. What is the use of March winds?
Q. Why does “March come in like a lion?”
A. Because it comes in with blustering east winds, which are essential to dry the soil, which would otherwise rot the seed committed to it.
Q. Why does “March go out like a lamb?”
A. Because the water (evaporated by the high winds) falls again in showers to fertilize the earth, and breaks the violence of the winds.
Q. Why is it said that “A bushel of March dust is worth the king’s ransom?”
A. Because it indicates that there has been a continuance of dry weather; and unless March be dry, the seed will rot in the wet soil.
Q. Why is it said “A dry cold March never begs bread?”
A. Because the dry cold winds of March prepare the soil for seeds, which germinate, and produce fruit in the autumn.
A. Because, if March be wet, so much of the seed rots in the ground, that the autumn crops are spoiled.
Q. Why is it said that “March flowers make no summer bowers?”
A. Because, if the spring be very mild, vegetation gets too forward, and is pinched by the nightly frosts, so as to produce neither fruits nor flowers.
Q. Why is it said “A late spring makes a fruitful year?”
A. Because if the vegetation of spring be backward, the frosty nights will do no harm; for the fruits and flowers will not put forth their tender shoots, till the nights become too warm to injure them.
Q. Why is it said that “April showers bring May flowers?”
A. Before seeds can germinate, three things are essential:—Darkness, Heat, and Moisture. April showers supply the principal nourishment on which seeds depend for existence.
A. Yes; rain-water contains “ammonia,” to which much of its fertilizing power may be attributed.
(Ammonia is a compound of nitrogen and hydrogen. Common hartshorn is only ammonia and water.)
Q. Why has God made November a very rainy month?
A. Because the rain hastens the putrefaction of the fallen leaves, and this makes the earth fertile.
Q. Why is there more rain from September to March than from March to September?
A. From September to March, the temperature of the air is constantly decreasing; on which account, its capacity for holding vapour is on the decrease, and the vapour is precipitated as rain.
Q. Why is there less rain from March to September, than from September to March?
A. From March to September, the temperature of the air is constantly increasing; on which account, its capacity for holding vapour is on the increase, and very little is precipitated as rain.
Q. Why is the rising sun in summer accompanied with a breeze?
Q. How does this warmth produce a breeze?
A. The air (resting on the earth’s surface) is warmed by contact, ascends upwards, and colder air rushes in to fill up the void, which is the cause of the morning breeze.
Q. Why is there often an evening breeze during the summer months?
A. The earth radiates heat at sun-set, and the air is cooled down quickly by contact: this condensation causes a motion in the air, which is the evening breeze.
Q. Why are tropical islands always subject to a sea-breeze every morning (i. e.. a breeze blowing from the sea to the land)?
A. The solar rays are unable to heat the surface of the sea as they do the earth; therefore, the air resting on the earth is more heated than the air resting on the sea; and the colder sea air blows inland to restore the equilibrium.
A. Because it is frequently loaded with exhalations from putrefying animal and vegetable substances.
Q. Why is the sea breeze fresh and healthy?
A. Because it passes over the fresh sea, and is not laden with noxious exhalations.
It is healthy, therefore, to walk on the sea-beach before ten o’clock in the morning; but unhealthy after sun-set.
Q. Why is there generally a fresh breeze from the sea (in English watering places) during the summer and autumn mornings?
A. As the land is more heated by the sun than the sea; therefore, air resting on the land is hotter than air resting on the sea; in consequence of which, cooler sea air glides inland, to restore the equilibrium.
Q. Why does the sea breeze feel cool?
Q. Why are tropical islands subject to a land breeze every evening (i. e.. a breeze blowing from the land towards the sea)?
A. The surface of land cools down faster (after sun-set) than the surface of the sea: in consequence of which, the air of the cold land is condensed, sinks down, and spreads itself into the warmer sea air, causing the land breeze.
Q. Why is the land breeze cool?
A. As the surface of the land is cooled at sun-set quicker than the surface of the sea; therefore, the seaman feels the air from the land to be chill.
Q. Why is the temperature of islands more equable than that of continents?
A. Because the water around the island absorbs the extreme heat of summer, and gives out heat to mitigate the extreme cold of winter.
Q. Why does the sea round an island give out heat in winter?
Q. Why are there waves in the sea?
A. The wind (acting on the surface of the sea) piles up ridges of water, which leave behind an indentation: as the water on all sides rushes to fill up this indentation, the disturbance spreads on all sides, and billow rolls after billow.
Q. Why does wind in England generally feel cold?
A. Because a constantly changing surface comes in contact with our body, to draw off its heat.
Q. Why is a room (even without a fire) generally warmer than the open air?
A. As the air in a room is not subject to much change, it soon becomes of the same temperature as our skin, and no longer feels cold.
Q. Why do we generally feel colder out-of-doors?
A. Because the air (which surrounds us) is always changing; and as fast as one portion of air has become warmer by contact with our body, another colder portion surrounds us to absorb more heat.
A. Blowing causes the air (which covers the hot food) to change more rapidly; in consequence of which, the hot air is quickly blown away, and gives place to fresh cold air.
Q. Why do ladies fan themselves in hot weather?
A. By the action of the fan, fresh particles of air are perpetually brought in contact with the face, and every fresh particle of air absorbs some heat from the skin.
Q. Does the fan cool the air?
A. No; it makes the air hotter, by imparting to it the heat out of our face: but it cools the face blown upon, by transferring its heat to the air.
Q. Is the air in summer time ever so hot as our bodies?
A. No, not in England. In the hottest day in summer, the air of England is 15 or 20 degrees cooler than the human body.
Q. How fast does wind travel?
Q. How is the velocity of winds ascertained?
A. By observing the velocity of the clouds, and by an instrument for the purpose.
This instrument is called an Anemometer.
Q. How is the velocity of the clouds ascertained?
A. By observing the speed of their shadow along the ground; which is found in a high wind to vary from 20 to 60 miles an hour.
Q. Why is there always a strong draught through the keyhole of a door?
A. As the air of the room we occupy is warmer than the air in the hall, therefore the cold hall air rushes through the keyhole into the room, and causes a draught.
Q. Why is there always a strong draught under the door, and through the crevice on each side?
Q. Why is there always a draught through the window crevices?
A. The external air (being colder than the air of the room we occupy) rushes through the window crevices to supply the deficiency, caused by the escape of air up the chimney, &c.
Q. Why is there more draught if you open the lower sash of a window, than if you open the UPPER sash?
A. If the lower sash be open, the cold external air will rush more freely into the room; but if the upper sash be open the heated air of the room will rush out; and (of course) there will be less draught.
Q. By which means is the room better ventilated, by opening the lower or the upper sash?
A. A room is better ventilated by opening the upper sash; because the hot vitiated air (which always ascends towards the ceiling) can better escape.
A. A hot room is cooled more quickly by opening the lower sash; because the cold air can enter more freely by an under current, than by one higher up.
Q. Why does wind dry damp linen?
A. Because dry wind (like a dry sponge) imbibes the particles of vapour from the surface of the linen, as fast as they are formed.
Q. Which is the hottest place in a church, chapel, or theatre?
A. The gallery.
Q. Why is the gallery of all public places hotter than the lower parts of the building?
A. Because the heated air of the room ascends, and all the cold air (which can enter through the doors and windows) keeps to the floor, till it has become heated.
Q. Why do plants often grow out of walls and towers?
A. Because sometimes the wind blows the seed there with the dust; and sometimes birds (flying over) drop the seed which they had formerly eaten.
Q. What is a barometer?
A. A weather-glass, or instrument to show the changes of the weather, by marking the variations in the weight of air.
Q. What is a thermometer?
A. An instrument to show how hot or cold anything is.
Q. What is the difference between a thermometer and a barometer?
A. In a thermometer the mercury is sealed up from the air:
In a barometer the mercury is left exposed (or open) to the air.
Q. If the mercury of the thermometer be sealed up from the air, how can the air affect it?
Q. Why is the tube of a barometer left open?
A. That the air may press upon it freely; and as this pressure is more or less, the mercury rises or falls in the tube.
Q. How can weather be affected by the weight of the air?
A. When air is warm or moist, it is lighter than usual:
When it is cold or dry, it is heavier: and as a barometer marks whether the air be light or heavy, it indicates these changes.
Q. How can you tell (by looking at a barometer) what kind of weather it will be?
A. Because the mercury in the tube rises and falls, as the air becomes lighter or heavier: and we can generally tell by the weight of the air, what kind of weather to expect.
Q. Does the weight of the air vary much?
A. Yes; the atmosphere in England varies as much as one-tenth part more or less.
Q. What is the chief use of a barometer?
Q. How can a barometer warn sailors to regulate their ships?
A. As the barometer will tell when wind, rain, or storm is at hand, the sailor can make his ship trim before it overtakes him.
Q. Are there any rules which can be depended on?
A. Yes; there are ten special rules to direct us how to know the changes of weather, by marking the mercury of a barometer.
Q. What is the 1ST SPECIAL RULE in regard to the barometer?
A. The barometer is highest of all during a long frost; and it generally rises with a north-east wind.
Q. Why is the barometer highest of all during a long frost?
A. Because long frost condenses the air very greatly; and the more air is condensed, the greater is its pressure on the mercury of the barometer.
Q. Why does the barometer generally rise with a north-east wind?
Q. What is the 2ND SPECIAL RULE in regard to the barometer?
A. The barometer is lowest of all during a thaw which follows a long frost: it generally falls with south and western winds.
Q. Why does the barometer fall lowest of all at the breaking up of a long frost?
A. 1st—Because the air (which had been much dried by the frost) absorbs the moisture of the fresh warm current of wind from the south or south-west: and
2ndly—The air (which had been much condensed by the frost) is suddenly expanded by the warm wind which is introduced.
Q. Why does the barometer fall very low with south and west winds?
A. Because south and west winds come heavily laden with vapour; and vaporized air is lighter than dry air.
Q. What effect has wind on the mercury?
Q. Why do winds generally make the mercury of a barometer drop?
A. Wind is caused by a partial vacuum in some parts of the globe; and as the air rushes in to supply this deficiency, its general pressure is lessened, and the barometer falls.
Q. What is the 3RD SPECIAL RULE in regard to the barometer?
A. While the barometer stands above 30°, the air must be very dry or very cold, or perhaps both, and no rain may be expected.
Q. Why will there be no rain if the air be very dry?
A. If the air be very dry it will absorb moisture, and not part with what it has in rain.
Q. Why will there be no rain if the air be very cold?
Q. What is the 4TH SPECIAL RULE in regard to the barometer?
A. When the barometer stands very low indeed, there is never much rain, although a fine day will seldom occur at such times.
Q. What kind of weather will it be when the barometer is unusually low?
A. There will be short heavy showers, with sudden squalls of wind from the west.
Q. Why will there be very little rain if the barometer be unusually low?
A. Because the air must be very warm, or very moist, or perhaps both.
Q. Why will there be little or no rain, if the air be very warm?
A. If the air be very warm it will have a tendency to imbibe more moisture, and not to part with what it has.
Q. Why will there be little or no rain if the air be moist, and the barometer remains very low?
Q. What is the 5TH SPECIAL RULE in regard to the barometer?
A. In summer-time (after a long continuance of fair weather) the barometer will fall gradually for 2 or 3 days before rain comes; but if the fall of the mercury be very sudden, a thunder-storm is at hand.
Q. What is the 6TH SPECIAL RULE in regard to the barometer?
A. When the sky is cloudless, and seems to promise fair weather, if the barometer be low, the face of the sky will soon be suddenly overcast.
Q. What is the 7TH SPECIAL RULE in regard to the barometer?
A. Dark dense clouds will pass over without rain, when the barometer is high; but if the barometer be low, it will often rain without any gathering of clouds.
Q. What is the 8TH SPECIAL RULE in regard to the barometer?
A. The higher the barometer, the greater is the probability of fair weather.
A. Because the air contains but very little vapour. The drier the air, the higher does the mercury of the barometer rise.
Q. What is the 9TH SPECIAL RULE in regard to the barometer?
A. When the mercury is in a rising state, fine weather is at hand; but when the mercury is in a sinking state, foul weather is near.
Q. Why does the mercury rise at the approach of fine weather?
A. Because the air is becoming more dry, and therefore its pressure is greater.
Q. Why does the mercury sink at the approach of foul weather?
A. Because the air is laden with vapour, or disturbed by wind.
Q. Why does vapour in the air make the mercury sink?
A. Because vaporized air is lighter than dry air, and therefore its pressure is less on the mercury of the barometer.
A. If (in frosty weather) it begins to snow, the barometer generally rises to 32°, where it remains as long as the snow continues to fall; if, after this, the weather clear up, you may expect very severe cold.
Q. How can you know if the mercury of the barometer be rising?
A. If it be convex (i. e. higher in the middle than at the sides;) it is in a rising state.
Q. How can you tell if the mercury of the barometer be about to fall?
A. If it be concave (i. e. hollow in the middle) it is in a falling state.
Q. Why is the mercury convex when it is rising?
A. The sides of the mercury rub against the glass tube, and are delayed by it, so that the middle part rises faster than the sides.
Q. Why is the mercury concave when it is falling?
Q. What effect does a thunder-storm produce on the weather?
A. Thunder is generally preceded by hot weather, and followed by cold and showery weather.
Q. What effect does a sudden change produce on the weather?
A. A great and sudden change (either from hot to cold, or from cold to hot) is generally followed by rain within 24 hours.
Q. Why is a sudden change from hot to cold followed by rain?
A. The cold condenses the air and its vapour; which, being condensed and squeezed out, falls in rain.
Q. Why is a sudden change from cold to hot followed by rain?
A. Because the air is quickly saturated with moisture; and as soon as night comes on, the temperature is lowered again, and some of the abundant moisture falls in rain.
Q. Why is the air quickly saturated with moisture, when heat succeeds rapidly from cold?
Q. When does the barometer vary most?
A. In winter time.
Q. Why does the barometer vary more in winter than in summer time?
A. Because the difference of temperature between the torrid and temperate zones is so great, that the state of the air is perpetually disturbed by their mixing together.
Q. When does the barometer vary least?
A. In summer time.
Q. Why does the barometer vary less in summer than in winter time?
A. Because the temperature of our island is so nearly equal to that of the torrid zone, that its state is not much disturbed by interchange of currents.
Q. What effect has wind on the barometer?
Q. Have heat and cold any effect on the barometer?
A. No, not of themselves; but because cold weather is generally either dry, or rough with north-east winds, therefore the mercury rises in cold weather; and because warm weather is often moist or fanned by south-west winds, therefore, the mercury sinks.
Q. Why is the mercury of a barometer lower in the torrid than in the frigid zones?
A. Because the warm air of the torrid zone contains much more vapour than the condensed air of the frigid zone; and the moister the air, the less is its pressure.
Q. In what months is the barometer highest?
A. In May and August; next to these, in June, March, September, and April.
Q. In what months is the barometer lowest?
A. In November and February; then in October, July, December, and January.
Q. What are the wettest months?
A. October and February; then July and September; then January and December.
Q. Why is there less wet from March to August, than there is from August to March?
A. Because the heat is constantly increasing; and the capacity of the air to absorb and retain moisture increases likewise.
Q. Why is there more wet from August to March, than there is from March to August?
A. Because the heat is constantly decreasing, and the capacity of the air to retain moisture decreases also; so that (although it often rains) yet the air is always on the point of saturation.
Q. Why does the mercury of a barometer rise in a frost?
A. Because frost condenses the air; and condensed air is heavier than rarefied air.
Q. Why does the mercury of a barometer fall in a thaw?
Q. What does a sudden rise or fall of the barometer indicate?
A. If the rise be sudden, fine weather will not continue long:
If the fall be sudden, foul weather will not continue long.
Q. What sort of weather may we expect if the barometer be very fluctuating?
A. If the mercury fluctuates much, the weather will be very changeable and unsettled.
The fall of the barometer.
In very hot weather, the fall of the mercury denotes thunder.
Except in very hot weather, the sudden falling of the barometer denotes high wind.
In frosty weather, the fall of the barometer denotes thaw.
If wet weather happens soon after the fall of the barometer, expect but little of it.
In wet weather if the barometer falls, expect much wet.
In fair weather, if the barometer falls much and remains low, expect much wet in a few days, and probably wind.
N. B. The barometer sinks lowest of all for wind and rain together, next to that for wind (except it be an east or north-east wind).
The rise of the barometer.
In winter the rise of the barometer presages frost.
In frosty weather, the rise of the barometer presages snow.
If fair weather happens soon after the rise of the barometer, expect but little of it.
In wet weather, if the mercury rises high and remains so, expect continued fine weather in a day or two.
In wet weather, if the mercury rises suddenly very high, fine weather will not last long.
N. B. The barometer rises highest of all for north and east winds; for all other winds it sinks.
If the barometer be unsettled.
If the motion of the mercury be unsettled, expect unsettled weather.
If it stand at “much rain” and rise to “changeable,” expects fair weather of short continuance.
If it stand at “fair” and fall to “changeable,” expect foul weather.
N. B. Its motion upwards indicates the approach of fine weather: its motion downwards indicates the approach of foul weather.