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275

1° 20 30

etc.

bromine, or sulphur, forming H,O, HCI, HI, HBr, and H,s no similar co-efficient for solids, for all differ in their expansions, respectively. The experiment is arranged as in Fig. 24. B is whereas gases expand alike. a tube packed with calcium chloride, which takes all moisture The alteration in volume for a change of temperature is easily from the gas (this is not actually necessary). c is a "reduction foundtube."* Place in the bulb a little black oxide of copper, and

273 volumes of gas at 00 Cent. apply heat. The hydrogen will take the oxygen, forming H,O,

become 274 and the metallic copper will be found in the bulb. Thus

276 CuO + H, = 1,0 + Cu.

eto. The same experiment may be performed with iron filings.

273+t Iron has such a strong affinity for oxygen that it is never ob- If, therefore, we require to know what volume 500 litres of tained in a pure state, save by this means. The filings will hydrogen at 50° would become at 120°, we ask what 273 litres assume the colour of pure iron-dark blue; and when scattered do under the same circumstances. 273 would become 323 at out of the tube into the air, so rapidly do they combine with 50°, and 493 at 120° : hence this proportion will give us the the oxygen again, that they become red-hot.

required volume : THE DIFFUSION OF GASES.

As 323 : 493 : : 500 : the new volume. If oil and water and mercury be shaken in a bottle for any For Fahrenheit degrees the expansion will be dis *} = idz of the length of time, the moment the motion ceases the mercury will volume at 32° for each degree. It is right to observe that this sink to the bottom and the oil rise to the top, but this is not the law is not absolutely accurate; yet it is sufficiently so for all case with gases; if it were, our world would not be habitable. practical purposes.

Take two flasks, and connect them by a small tube passing The reader will note that the increment is a fraction of the through the cork of each. Place them as in Fig. 25; fill the volume at zero, and therefore an absolute quantity; if it were top one with lıydrogen, and the other with carbonic acid-a very a fraction of the volume at any temperature, the increment would

heavy gas—and it will be found that the be variable.
gases mix, the carbonic acid rising, and the It will be evident from the above that it is necessary to have
hydrogen falling.

a standard temperature, to which to reduce all gases, in order This fact may be strikingly shown by that they may be compared under the same circumstances. The

plugging ap the end of a long tube with a temperature of melting ice, or 0° Centigrade, has been fixed H

little plaster of Paris. Moisten the powder upon.
into a clay, and then place some in the end EFFECT OF PRESSURE ON THE VOLUME OF GASES.
of the tube-quickly, for it soon "sets.”

Boyle, an English, and Mariotte, a French philosopher, dis-
Now fill the tube with hydrogen, and stand covered independently of each other the law which bears their
it in a glass containing some coloured name-Boyle and Mariotte's law—"The volume of a gas is in.
water, and the water will be found to rise versely proportional to the pressure to which it is subjected.”.
in the tube, for the hydrogen passes out

If, for instance, a litre of gas supports a pressure of 1 kilothrough the plug with greater rapidity than the air passes in; hence the water rises.

gramme, and the pressure be increased to 2 kilogrammes, the It has been discovered that the rate of exerted on gases is the weight of the atmo

volume will soon become į a litre. The pressure generally diffusion of different gases is inversely pro- sphere, which is measured by the barometer. portional to the square root of their densities. If a glass tube, A B (Fig. 26), sealed at one Thus oxygen is 16 times heavier than end, and about one yard long, be filled with hydrogen; the square root of 16 is 4, and mercury, and then inverted into a vessel also that of 1 is 1: therefore hydrogen passes containing that metal, the mercury in the through the diaphragm 4 times faster than tube will be found to fall, leaving a space, AC, oxygen.

of about six inches empty; this is called As hydrogen is the lightest of all bodies, “Torricelli's vacuum.” That is, the column it is taken as the standard, and if we know of mercury in the tube is exactly the weight its weight we can always find that of any of a column of air its own size, to the top other gas; for the densities of all these of the atmosphere. If from any cause the

elements, which can be got in the gaseous weight of the air alter, the mercury will Fig. 25. state, are identical with their atomic weights. rise or fall accordingly. The standard

There are, however, two notable exceptions to this law, phosphorus and arsenic, whose vapours have densities pressure of the atmosphere is in English 30

inches, in French 760 millimètres. If the just twice their atomic weights. In the case of almost all compound gases, the density is half 30 inches of mercury would weigh 14:67

tube were a square inch in surface, then the combining weight.

lbs., or the pressure of the atmosphere on The weight of a litre of hydrogen at Cent. and 760 mm.

every square inch is 14.67 lbs. When great (millimètres) pressure (the standard temperature and pressure) is pressures are used, they are measured by Therefore at the same temperature and

"atmospheres." For instance, we say a pressure

gas liquefies with a pressure of 35 atmo1 litre of 0 weighs 16 x '08935

spheres, which will equal 35 X 14:67=
1 litre of Cl weighs 35.5 x .08936

513.45 lbs. on every square inch.
1 litre of Co, weighs
According to Boyle and Mariotte's law,

B
whenever we want to find the alteration the
36-5
1 litre of HCl weighs

volume of a gas undergoes by a change of

pressure, we form with the new pressure
etc.
etc.

and the standard pressure, 760 mm., a fracIt is necessary to have a standard of temperature and pres- tion. If the pressure be increased 760 must sure, since the volumes of gases are very much altered by a

be the numerator, if diminished the denomi. change in either.

nator, and by this fraction we multiply the Fig. 26.

original volume of the gas. For example: EFFECT OF CHANGE OF TEMPERATURE ON GASES. It has been found by careful experiment that when heated would be their volume at the standard pressure? Here the

500 litres of air are now under the pressure of 712 mm.; what gases expand the as part of their volume at 0° for every degree pressure will be increased, hence the volume diminished; the is called “ the co-efficient of the expansion of gases.” There is fraction must therefore be less than unity.

500 x 712 * Woulf's bottles, 8-oz. capacity, Is. 4d.; "reduction tubes," 6d.

= 468.4 litres. 760

0-08936 grammes.

X *08936

X 08935

2

273

21.38

In the following example the volume of a gas will be "cor. 1,000 feet, the product of the numbers which represent the pounds rected" for temperature and pressure :

raised and the feet passed over being the same in each case. What weight of potassium chlorate will be required to fill a Thus we can find the work done in any machine, and we have gas bag of a capacity of 20 litres, the temperature of the room another way of putting the principle of virtual velocities, the being 15° Cent., and the pressure of the air at the same time work done by the power being always equal to that done by the 750 mm. ?

weight. By reducing to this unit the work done by the same KC103 = KCI + 0,

force applied in different modes, we can discover which is the 39:1 + 35.5 + 48 = 89·1 + 85.5 + 48;

most advantageous, and what is their comparative efficacy. or 122:6 parts by weight of KC10, give off 48 of O, or 100 parts We will now inquire into the different ways of applying human of the salt yield 39.2 of the gas. We know that the weight of power. In spade labour there is a very great loss. When a litre of oxygen at the standard temperature and pressure will merely used for turning up the ground, the spade is a lever of be 16 X 0.08936 grammes = 1.4298 grammes; therefore 20 the first kind, and the power acts at the longer arm; but when litres will weigh 1.4298 X 20 = 28.596 grammes.

the earth is lifted or thrown to any height, the spade becomes a We must know first what volume 20 litres would occupy at lever of the first or third kind, according to which hand we conthe given temperature and pressure.

sider the fulcrum and which the power; but either way, the

273 + 15 weight acts at the longer arm, and thus causes a great waste To correct for temperaturo we must multiply 20 by

of power.

In turning a winch, though a larger portion of the 760 and for pressure by

20 x 760X (273 + 15) force employed is utilised, there is still great loss and irregularity. 750 ; or at one operation,

273 x 750 When the handle is being pulled upwards and towards the person = 21:38 litres at 15° Cent. and 750 mm.

who is turning it, his force produces the greatest effect; the The weight of the gas has not been altered, and therefore this next greatest effect is produced when it has passed the highest 21.38 litres at 15° Cent. and 750 mm. weighs what it did when it point, and is being pressed downwards, but evidently the pressure was 20 litres at oo and 760 mm., that is, 28-596 grammes. is now limited to his own weight. When the handle is being What, then, will 20 litres of this more rarefied gas weigh? This pushed or pulled horizontally, still less is accomplished. If we proportion will give the answer

raise any weight by a winch, we shall easily feel these differences

in the strain.
28 596 x 20
21:38 : 20 : : 28596 :

267 grains.

In some modes of applying force nearly all the muscles of the

body are set to work, and the strain is distributed, while in How much potassium chlorate will be required to yield 26:7 others only a few act, and hence fatigue soon follows. When a grammes of oxygen, when 100 yield 39.2 ?

boat is propelled by oars, the force exerted is applied very 39-2 : 267 : : 100 : 68·11.

advantageously; nearly all the body helps, and the strain is in

the most favourable direction. When the foot is firmly planted Therefore 68'11 grammes of potassium chlorate will yield suffi- against the foot-board, the strong muscles of the back and cient gas to fill a bag of 20 litres at 20° Cent, and 750 mm. thighs exert their force; the hands, too, pull in a direction pressure.

nearly at right angles with the oars. Hence we find that the

amount of work a man can accomplish this way is half as great MECHANICS.-XV.

again as he can by turning a winch. PRIME MOVERS-ANIMAL FORCE, WATER, WIND, STEAM. advantage is gained is by ascending a ladder, and then allowing

The mode of employing human power by which the greatest HAVING in our last lesson seen a few of the principal ways of the weight of the body to act, and, by descending, raise a weight transmitting and modifying motion, we will now notice the most nearly equal to itself. An interval of rest is gained in this way important of the prime movers or causes of motion, and then while descending, and experience shows that more work can be pass on to Dynamics.

accomplished if frequent short intervals of rest are thus taken As already stated, no machine can create force, there must be between short periods of work. The body being specially some original sourco whence it proceeds ; and on examination we framed for walking, nearly all the force expended is effective. shall find that nearly all sources of power may be divided into When a large amount of heavy matter, such as building these four classes: muscular action, whether of men or animals; material, or earth for an embankment, has to be raised to s the force of water; the power of the wind; and the expansive height, human power is sometimes thus applied :-A bucket in power of gases or vapours. There are a few other prime movers, which a man can sit, or the material to be raised can be placed, as electricity, heat, and chemical action; these, however, are not is fixed at each end of a rope, which passes over a pulley fixed a used at all in practice, but merely for the sake of experi. little above the level to which the material has to be raised. The ment, their cost being at present too great to allow of their iength of the rope is so adjusted, that when one bucket is on the employment.

ground, the other shall be at the required height. The lower Muscular action, the first of our four kinds, is the one earliest bucket is then loaded, and one or more men ascend a ladder or employed and most frequently used, when no very great exertion incline and enter the upper one; their weight causes it to is required. The reason of this is, that it can always be em- descend, and thus the material is raised. Nearly all the labour ployed without previous arrangement, and can readily be is thus expended in raising themselves to the top of the ladder

, applied in almost any way that may be needed; it is, how- and while they are descending, and the material is being removed ever, one of the most uncertain of the prime movers, as it is from the upper bucket, they have an interval of rest. In the both limited in its power and irregular in its action. The two treadmill the power is applied in a very similar way. This divisions of it are, the force of men and that of animals. But consists essentially of a large and very broad wheel, with steps before noticing these we must decide what unit of work we fixed all round it; the men hold on to a fixed bar, and attempt are to adopt. In our second lesson we saw that the unit of to ascend the steps. The wheel, however, turns with their weight force is that which is required to cause a round ball, equal in as fast as they ascend, and thus they do not raise themselves at weight to a cubic inch of water, to move through one foot in all; but still the principle is the same,

and nearly as much effect one second, and that this unit is equal to 7.85 grains. This is

, is gained from the power in this way as in the former, the slight however, far too small for practical purposes, and the unit of difference arising mainly from the fact that the intervals of rest work which has been fixed on and universally adopted in this are less frequent. country in calculations like those we are about to make, is the In some quarries the mineral is raised in a similar way, by force required to raise a weight of 1 pound through a space of 1 men climbing on cross-pieces fixed through the rim of a very foot. We call this the unit of work, and not of force, as time largo wheel, round the axle of which the rope winds. This is is not taken into account. The same amount of work is done in an example of the employment of the wheel and axle; the raising 100 pounds to a height of 50 feet, whether a minute or power,

however, does not act at the circumference of the large an hour be occupied; the

force required would, however, be much wheel, for the men are not on a level with the axle, but at a greater in the former than in the latter case. This unit of work radius which varies with the weight to be raised. is called a foot-pound. In the example just taken, 50 x 100, that To calculate the gain, we must imagine a vertical line to pass is, 5,000 units or foot-pounds, are required to raise the weight. through the centre of gravity of the men ; this line will meet the The same force

would also raise 5,000 pounds 1 foot, or 5 pounds spoke which is horizontal in some point, and the distance of this

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point from the centre is the radius at which the power really The next of the prime movers is the force of the wind. Heat acts. Hence, when the weight to be raised is greater, the men expands all substances; hence, when any place is greatly heated are higher up on the wheel, and thus their weight acts at a by the sun's rays, the air over it expands and rises, and cold greater leverage. Animal power is sometimes applied in a air from around rushes in to fill its place. This air in motion similar way, the animal being made to walk round the inside is called wind, and produces the effects with which all are of a large cylinder, and thus to turn it.

familiar. It acquires momentum as it travels, and when any The following table, which is the result of many experiments object obstructs it, presses against the obstacle with a force proand calculations by different scientific men, shows approxi- portional to its speed. This pressure produces the greatest mately the effec! produced by human power when employed effect when it acts in the direction in which motion is required, in diferent ways, and gives us a good idea of their comparative as, for instance, when a ship is propelled by a stern wind. The efficacy. The average duration of the labour may be reckoned sails are spread as nearly as possible across the ship, and the at eight hours per day.

full force of the wind drives it onward. UNIT OF WORK DONE BY A MAN IN A DAY.

If the vanes of a windmill aro arranged like the float of a Raising his own body

2,000,000 paddle-wheel, so that the wind acts sideways on the wheel, no Rowing a boat

1,900,000

effect will be produced unless one-half of it is protected from Working at a treadmili

1,870,000

the wind; for its action on those floats which are uppermost Pushing or drawing a carriage

1,500,000 tends to turn the wheel one way with exactly the same force that Turning a winch

1,250,000 its action on the lower ones does the other way. Even if the Working a pile engine by hand

1,000,000 lower half be thus shielded the wind acts on those at the side Throwing earth with a spade

500,000

very obliquely, and these keep it off from the vertical ones. We now pass to the power of animals, which is much more Hence little effect can be gained in this way, and the vanes are frequently applied than that of man-it being found better to always arranged so as to make a small angle with the plane in employ man where skill and thought, and not mere mechanical which they revolve, and it is found that most effect is produced labour, are required; hence skilled labour is always more highly when different parts of the vane have a different inclination, paid than unskilled. The animal most commonly employed in those nearest the centre being inclined at a greater angle than this country is the horse, and Watt estimated the amount of those more remote. We saw in our last lesson how in all such work it was capable of performing at 33,000 foot-pounds per cases to ascertain what portion of the force of the wind is thus minute. This amount was accordingly adopted as a unit of rendered effective. measurement, and is called a horse-power. Thus, when we speak The fourth, and in some respects the most important of the of a steam-engine of 12 horse-power, we mean one capable of prime movers, is the expansive force of gases and vapours. raising 12 times 33,000, which is 396,000 pounds, 1 foot high in The great advantage of this class is, that an almost unlimited 1 minute, or 1,000 pounds 396 feet, for each requires the same amount of power may always be obtained, and that the cost is amount of power. Though this unit of measurement is still much less. Wind and water power often fail, but a steamretained, it is more than a horse can accomplish continuously, engine, which is the most common example of this class of prime and in practice its power is not found to be more than 22,000 movers, can work as well at one time as another. units, or of the nominal amount. The power of a mule is about

We cannot stop now to explain the details of the construction s that of a horse, while that of an ass is only .

of an engine, but the principle on which it acts is simply this :The most common way of employing animal power is in When water is heated to 212°, a portion of it is converted into drawing or carrying a load, and it is clear that if this load be an invisible vapour called steam; this occupies a space nearly increased, the speed with which it is carried must be diminished. 1,800 times as large as the water, and we have thus an expansive Hence it is an important question to decide at what rate of force which is utilised and converted into any kind of motion motion the greatest effect can be obtained, and the best way of we may require. The usual plan of employing it is to procure a determining this is by experiment. There are two extreme large cylinder, with a piston capable of moving up and down in it; cases: the animal may sustain so heavy a load that it can the pressure of the steam is first caused to act below this piston, scarcely move; or, on the other hand, it may travel very rapidly, which it drives to the top of the cylinder ; by an arrangement bat without being able to carry any load at all. The greatest of the valves the steam is then caused to act above instead of effect is at some intermediate speed, and the weight that can be below, and thus an alternating motion is produced from the prescarried varies inversely as the speed. The useful effect is the sure, and this is, by means of a crank, changed into one of rotation, product of the numbers which represent the speed and the load. If we have a piston with a surface of one square inch, the Thus, if a horse can carry 12 hundred-weight 6 miles an hour, evaporation of a cubic inch of water will raise it 1,800 inches, or 15 hundred-weight 5 miles an hour, it is most advantageous or 150 feet. Now the pressure of the air on the piston is 15 to let him take the heavier load, the useful effect then being pounds, and as this is overcome, the work done is 15 pounds 15x5, or 75, while in the other case it is 12x6, or 72 only.

raised 150 feet. This is 2,250 foot-pounds; or, to put it in a Now, it is found that the largest amount of work is done by way more easy to remember, the evaporation of a cubic inch of giving such a load that the animal can travel about three miles water will produce force enough to raise a ton to a height of 1 foot. an hour; if the speed be increased much beyond this, the weight

Now this force is not created; something must be consumed must be diminished in a more than equal proportion.

in order to produce it, and this something is the fuel employed. The second prime mover is the force of water. Of this, how. A very important question, therefore, is to ascertain how much ever, we shall treat more fully when we pass on to Hydrostatics, work ought to be accomplished by a given quantity of fuel. Of and need, therefore, say little now. We may have the force of a course this varies much with the construction of the furnace and running stream, or that of the ebb and flow of the tide. The boiler, but it is reckoned that a pound of good coal will, when latter of these is a source of power very little used, but which employed in the best way, evaporate about 240 cubic inches of might often be well employed." Water has always a tendency to water, and therefore produce a force of about 540,000 foot-pounds. obey the law of gravity and sink to the lowest point; in doing The explosive force of gunpowder and similar explosive comthis it presses against or moves any obstacle that opposes its pounds come under this class of prime movers, though they are motion, and this pressure may in many different ways be em- sometimes set down to chemical agency. ployed to drive machinery. The simplest mode of applying it When they are ignited they set free a large amount of different is seen in the common water-mill, where the stream presses gases, which occupy a space many hundred times greater than against the floats of the wheel, and thus turns it.

that of the substances themselves, and this sudden liberation We can calculate the force of a stream or waterfall by gives rise to the violent effects we are accustomed to see promeasuring the distance through which the water falls, and duced by their employment. multiplying the weight of the water by this, we thus obtain the We have thus seen what are the main moving forces, and are number of units of work it is capable of effecting. If, for now prepared to enter fully on the study of Dynamics. instance, 1,000 gallons of water pass every minute, and the fall is 6 feet, then, since a gallon of water weighs 10 pounds, we have a moving force of 1,000 X 10 X 6, which is 60,000 foot to a height of 70 feet ?

1. How many units of work are required to raise 60 gallons of water pounds. But even in the best modes of employing this, there is 2. What power must an engine have to raise 20 tons of a very great loss.

hour from a mine 400 feet deep?

EXAMPLES.

noon.

to sove.

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6

3. From what depth will an engine of 6 horse-power raise 8 tons

VOCABULARY. per hour? 4. How much coal will be consumed in raising 5,000 cubic feet of Abreuvoir, m., vater. Châtean, m., villa. Men-er, 1 ($ 49 (6)],

ing-place.

Colporteur, m., pedlar, to take, to lead. water from a depth of 90 feet, a cubic foot of water weighing 62}

Appel-er, 1 ($ 49 (4)], hareker.

Se promen-er, 1. ref. pounds ?

to call.

Donner à manger, to 5. How long will it take a man to raise 50 tons of material to a

[$ 49 (6) ), to walk or feed.

ride for pleasure. height of 60 feet by a windlass; and how long by ascending a ladder Après-midi, f., after.

Ecurie, f., stable. Récolt-er, 1, to gather and letting his own weight raise it!

Avoine, f., oats. Foin, m., hay.

in a crop, to harvest, ANSWERS TO EXAMPLES IN LESSON XIV.

Blé, m., wheat. Gel-er, 1 ($ 49 (5)], to Sem-er, 1 ($ 49 (0)), 1. The resultant is 15 pounds.

Cachet-er, 1 [$ 49 (4)], freese.

to seal.
2. The second force is 8 pounds.
3. Let be the point at which the ropes A B and Bc act on the barge.

EXERCISE 113.
Take B D and B E each to represent 100. Complete

1. Mènerez-vous vos enfants à l'école ? 2. Je les mènerai à
the parallelogram and join D E. Since D B E is 60°,
and D B and B E are equal, the triangle is equila: l'école et à l'église. 3. Le jardinier apportera-t-il des légumes
teral, and therefore D E is equal to 100, and G E au marché ? 4. Il en apportera. 5. Où mènerez-vous co
to 50. Now B F is the resultant of B D and B E, cheval ? 6. Je le mènerai à l'écurie. 7. Lui donnerez-vous à
and BG is evidently / BF. But BGR + G E = manger ? 8. Je lui donnerai du foin et de l'avoine. 9. Lai
BE", that is = 10,00); for B E= 100, and Ge= donnerez-vous de l'eau ? 10. Je le mènerai à l'abreuvoir. 11.

2,500; B Go must, then, be 7,500, and B G is the Paierez- (8 49 (2)] vous ce que vous devez ? 12. Ne voulezcsquare root of this, or 86.6. The whole resultant

vous pas vous promener ? 13. Je me promènerai cette aprèsis therefore 86.6 x 2, or 173.2. 4. If the wire be pulled in the middle, each midi. 14. Vous promènerez-vous à pied ou à cheval ? 15. Je

me promènerai à cheval, et ma sœur se promènera en voiture. half will exert a tension of 100

or nearly 16. Marcherez-vous beaucoup dans votre voyage à Paris ? 17. Fig. 91.

JU* + 2a,
69 pounds. The total force will therefore be a

Nous ne marcherons pas du tout. 18. N'appellerez- [$ 49 (4)] little over 13 pounds.

vous pas le colporteur ? 19. Je ne l'appellerai pas. 20. 5. A force of the weight, or 15 pounds, is required.

N'achèterez- [$ 49 (5)] vous pas ce château ? 21. Nous l'achèterons si nous pouvons. 22. Ne gèlera-t-il pas [$ 49 (5)) cette

nuit ? 23. Je ne le crois pas, il fait trop chaud. 24. Ne LESSONS IN FRENCH.-XXXII.

sèmerez- [$ 49 (6)] vous pas tout le blé que vous récolterez ? SECTION LIX.-THE TWO FUTURES, SIMPLE AND 25. Je n'en sèmerai qu'une partie, je vendrai le reste. 26. Je ANTERIOR [$ 124).

cachetterai mes lettres et je les porterai à la poste. 1. The future of every verb in the French language ends with

EXERCISE 114. rai, ras, ra, rons, rex, ront. 2. This tense, in all the regular verbs, as also in the irregular

1. Will not the gentleman call his children? 2. He will call verbs not mentioned in the next section, may be formed from his children and his sister's. 3. Will you not bring your chil

dren ? the present of the infinitive by changing the r of the first and

4. I cannot bring them. 5. Will you not take a ride second conjugations, and the oir and re of the third and this afternoon ? 6. We will ride in a carriage to-morrow. 7. fourth, into the terminations already given and here again re- Will you not buy my father's horses ? 8. I shall not buy them; peated.

I have no money. 9. Will you not call the pedlar? 10. I do 3. CONJUGATION OF THE FUTURE SIMPLE OF THE

not wish to call him; I do not wish to buy anything. 11. Will

you pay the tailor? 12. I will pay him for my coat. 13. Will REGULAR VERBS.

it not freeze to-morrow? 14. It will freeze to-morrow; it is chante -rai fini -rai

-rai rend -rai very cold. 15. Will you not sow oats in this field (champ) ? will sing will finish will receive will render

16. I will not sow oats ; I will sow wheat there. 17. Will you Tu parle

chéri
apercev

vend wilt speak

take your sister to school ? 18. I will take her there this afterwilt cherish wilt perceive wilt sell donne fourni

noon. 19. Will you not take your son to market ? 20. I will percev

tend shall give will furnish will gather will tend

not take him there. 21. Will not the gardener take his horse Nous cherche -rons puni -Tons concev -rons entend

to the watering-place ? 22. He will take him there. 23. Will will seek shall punish will conceive will hear

you give oats to your horse ? 24. I will give him hay. 25. Vous porte

saisi
dev
perd

Will you bring your son with you? 26. I will bring him towill carry will scize will owe will lose

morrow. 27. Will he bring his horse ? 28. He will bring his Ils aime -ront uni -ront décev -ront mord -ront horse and carriage. 29. Why do you carry that little child: 30

. will love will unite will decoive vill bito

He is too ill to ( pour) walk. 31. Will your brother sell his 4. The future anterior is merely the past participle of the property ? 32. He will only sell part of it. verb, conjugated with the future of one of the auxiliaries, avoir, étre :

SECTION LX.-IRREGULARITIES OF THE FUTURE. J'aurai fini ; je me serai flatté. I shall have done; I shall have flat

1. The two irregular verbs of the first conjugation, aller, to tered myself.

go, and envoyer, to send, make in the future j'irai, j'enverrai 5. The student, when rendering English into French, should

(see $ 62). be careful to distinguish will, taken as an auxiliary, from the enir, change that termination into iendrai, etc., for the future:

2.° All the verbs of the second conjugation, which end in same word employed as a principal verb. In this latter case, it is always equivalent to the verb to wish, or to be willing, and quérir

, to acquire ; conquérir

, to conquer; requérir, to requitetos

as tenir, to hold, venir, to come; je tiendrai, je viendrai. Aoshould not be rendered by the future of the verb, but by the mourir, to die; and courir, to run, and its compounds, double present of vouloir :

the r in the future : j'acquerrai, je mourrai, je courrai. Cueillir

, Ne voulez-vous pas lui écrire ? Will you not (are you not willing to) to gather, and its compounds, change the i preceding the r into

write to him?

e: je cueillerai. RÉSUMÉ OF EXAMPLES.

3. In the third conjugation, s'asseoir, to sit down, and seoir, Quand parlerez-vous à ce mon. When will you speak to that gentle to sit, make je m'assiérai and je sibrai. Falloir, to be necessary, sieur ?

vouloir, to be willing, and valoir, to be worth, make il faudra, je Vous fournira-t-il des provisions ? Will he furnish you provisions ? voudrai, and je vaudrai. Voir, to see, and revoir, to see again, Ils ne recevront pas leurs revenus. They will not receive their income. Ne vendrez-vous pas vos pro. Will you not sell your property ?

make je verrai, je reverrai. Pouvoir, to be able, makes je priétés ?

pourrai, and pourvoir, to provide, je pourvoirai. Savoir, to knok, Que voulez-vous avoir ? What do you wish to have ?

and avoir, to have, make je saurai, and j'aurai. Que veut lire votre frère ? What will your brother read ?

4. Être, to be, faire, to make, and its compounds, are the only Apporterez-vous des pommes ? Will you bring apples ?

verbs of the fourth conjugation which are irregular in the Nous amènerons nos enfants. We will bring our children,

future : je serai, je ferai, etc. arterez des légumes. You will bring vegetables.

5. The futures, simple and anterior, are used in French after

Je

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man 7

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