

KKY TO , KK.N.'II. 



EXK ,V.-I. II., |,age 331). 



1. l)o 71x1 fulfil your duty well? 2. Neither of ui fulflU it. 3. 

 Do UMJJ both m-.-l. to impose theuiiulvu* ? 4. Nuith. twk to expoao 

 their hves. 5. Do your father aud mother flud themselves t< 

 day ? . Neither of them is bettor. 7. Have you found fault with 

 mj writiuK or with uay secretary'* P 8. I have found fault with 

 sjtnnr. 9. Does not that author (1ml fault with everything t 10. 

 Ha fld fault with every book. 11. Do you flud anything to blame 

 in itP 12. Noithor he nor I find anything to blume (eciutir*) in it. 

 13. Hu or I will watch over your iuturonta. 14. Neither he nor I 

 hall ceaiMt watching vur your HOU'H conduct. 15. We will watch over 

 it, rutbt-r thuu I'm. I fault with it. 16. He uud I found ouraulve* toge- 

 ther at tho uj>iiititfil |iKu-.-. 17. Will oithor of you be there (b 

 frmmt tVr) P 18. Ono or the other will bo present. 19. Will either 

 he alerted president P 20. Neither will be elected. 21. How do you 

 like this ronst meat ? 22. I flnd it excellent. 23. I like this book (f 

 faU tint btok good). 24. I do iiot like it (I do not find it good). 25. I 

 find that well dono (I deem that well done). 



EXERCISE 164 (Vol. II., page 331). 



1. Comment trouvez-vous ce HvreP 2. Ni ma steur id moi ne 

 rausooB. 3. MM. voa freres outils trouvii lo diner bon ? 4. L'un et 

 1'autru Toot trouve' tri-s bon. 5. Le professeur n-t-il trouve' a redire a 

 rotre condnite P 6. II n'y a pas trouvd a rodire. 7. Ni lui ni mon 

 pore no trouvent B redire a ma conduite. 8. Veillent-ils a rotre con- 

 dnite, 1'nn et 1'nutru ? 9. Us veillent 1'un et 1'autru, a ma conduite et 

 a snea intri-tB. 10. Avez-vous rempli votre devoir, 1'un et 1'autre ? 

 11. Nona 1'ttvous rouipli. 12. N'avez-voua pas, 1'un et 1'autre, trouvd 

 a redire a mou Venture P 13. Ni 1'un ni 1'autre, nous u'y avons trouvd 

 a redire. 14. M" 1 ' 8 vos scaurs, ne so trouveut-elles pas mieux au- 

 jonrd'hni ? 15. L'une so trouvo mieux. 16. L'autre ne se trouve pas 

 si him. 17. Ces dames ne trouveut-elles pas a redire a tout P 18. 

 Kllee ue trouveut & redire a rien. 19. L'uu ou 1'uutre sera-t-il <Slu 

 prefet dn d^partement ? 20. Ni 1'un ni 1'autre ne sera e"lu. 21. Com- 

 ment trouvez-vous ce pain ? 22. Je le trouve fort bon. 23. Vos deux 

 amis aoot-ils arrives a tomps an rendez-vous ? 21. Ni I'un ni 1'autre 

 n'y Ataient a temps. 25. Trouvez-vous a redire a cola ? 26. Je n'y 

 tronve pas a redire. 27. Vous exposerez-vous, 1'un et 1'autre, a ce 

 danger P 28. Nous ne nous y exposerons pas. 29. Trouvez-vous a 

 redire a la conduite de mon secretaire ? 30. Je n'y trouve pas a 

 redire. 31. Trouvez-vous a redire a son ecriture ? 32. J'y trouve a 

 redire; car elle est tres mauvaise. 33. Ne veillerez-vous pas a mes 

 iatercta ? 34. Mon frere et moi, nous y veillerons. 35. Nous no 

 i pas de veiller a vos inte'rets. 



EXEBCISE 165 (Vol. II., page 331). 



L Did not most of your relations come to see you ? 2. Many came. 

 3. What has become of the others ? 4. I could not tell you what baa 

 become of them. 5. What will become of that young man if he does 

 not apply to study ? 6. I do not know what will become of him. 7. 

 I know that he will never become learned. 8. How many pictures 

 have yon left ? 9. I have only one picture left. 10. How much shall 

 you have Jeft, when you have made your purchases ? 11. I shall only 

 have a trifle left. 12. Has that apprentice become skilful in his 

 trade? 13. He has become skilful in it. 14. Was that gentleman 

 born blind, or has he become so ? 15. He bos become so. 16. Do 

 yon know what has become of those young men ? 17. They have be- 

 come physicians. 18. Do you not know what has become of my 

 books ? 19. They are mislaid. 20. Will you not become lame, if you 

 walk so much ? 21. I shall become lame and thin. 22. Did not the 

 crowd lose their way in the wood ? 23. The crowd lost their way in 

 it, and conld not flud it again. 24. A crowd of barbarians desolated 

 the country. 25. A crowd of ruined citizens filled the streets of 

 Stockholm. 



EXERCISE 166 (Vol. II., page 331). 



1. La pluport de vos amis ne sont-ils pas devenus riches ? 2. La 

 plopart (de wes amis) sout devenus pauvres. 3. Cette demoiselle n'est- 

 efle pas devenue savante ? 4. Je pense qu'elle ne deviendra jamaia 

 aavante. 5. L'armee ainericaiuo n'est-elle pas fort petite ? 6. L'arme'e 

 nsrthiunne est petite, mais la plupart des soldats ame'ricains sont tri-s 

 braves. 7. Pouvez-vous me dire ce qu'est devenu ce monsieur P 8. 

 Je ne saurais vous dire ce qu'il est devenu. 9. M. votre frere est-il 

 aveogte de naissance ? 10. Non, Monsieur, il 1'est devenu. 11. fites- 

 TO*S n^ boitenx ? 12. Non, Monsieur, je le suis devenu il y a trois 

 ans. 13. La plupart de vos heures ne sont-elles pas dSvoue'es au jeu f 

 14. Non, Monsieur, olios sont ddvouees a I'e'tude. 15. Combien de 

 rotie argent vous reste-t-il ? 16. II ue m'en resto que vingt-cinq 

 francs. 17. Savez-vous combien il me resto? 18. II ne vous reste 

 qu'ane bagatelle. 19. Combien vous restera-t-il domain ? 20. II ne 

 ioe restora que six francs. 21. II ne me restera que deux francs, 

 qoand j'aurai fait mes einplettes. 22. Qu'est devenue votre gram- 

 mairo ? 23. Je 1'ai e'ganta. 24. Savez-vous ce qu'est devenu mou 

 chapeau ? 25. Vous 1'avez laisstS sur la table. 26. Ce monsieur ne 

 deviendra-t-il pas aveugle ? 27. 11 ne deviendra pas aveugle, mais 

 bottom. 28. Votre fils est-il devenu habile dans son ?tat ? 29. II n'y 



est DM deveuu habile. 30. Qu'est-il devenu f 31. H s'wt fear* dans 

 le bois. 81 La foule iWt-elle 4faitfe ? 33. La plupart des soidato ia 

 sont<gar#s. St. Un nurfe d saaUrilles desoUrtnt notre pays. 



Fig. 54. 



MECHANICS. X. 



THK 8TEELtABD. 



ANOTHER weighing instrument U the steelyard, which (Fig. 54) 

 is a lever of the first order, to the short arm of which U attached 

 at b a hook from which the substance, w, to be weighed is 

 suspended, while on the long arm slides the movable counter- 

 poise P. The object aimed at in this instrument being that a 

 small weight, P, should balance a large one, w, on the hook, it 

 is clear that there must be a corresponding disproportion in the 

 arms the fulcrum, a, must be near one of the ends of the beam. 

 Further, since it is necessary that the steelyard should take an 

 horizontal position, both when loaded and unloaded at its hook, 

 it is essential that its own centre of gravity should lie some- 

 whore on the short arm ; for then the counterpoise can balance 

 it when placed in some position on the other arm, such as at O. 

 For this reason steelyards are made heavy at one end. 



To Graduate a Steelyard. The centre of gravity of the beam 

 being on the hook side of the fulcrum, let it be brought into an 

 horizontal position, 

 no weight being on 

 the hook. Then, as 

 proved in previous 

 lessons, the moment 

 of P is equal to the 

 moment of the beam, 

 that is, the weight of 

 the beam multiplied 

 into the distance of 

 its centre of gravity 

 from a vertical line 

 through the fulcrum, 

 is equal to P multi- 

 plied into the distance 



of o from that line. At the point o so found draw a line 

 across the beam ; that line represents the zero division of the 

 long arm, or the division at which P produces equilibrium, the 

 weight on tho hook being nothing, cipher, or zero. 



Now, supposing that any number of pounds, w, of any sub- 

 stance are hung on the hook, while P is shifted to the left until, 

 as in the figure, the arm is again horizontal, we have P multi- 

 plied by the distance of its ring from the fulcrum a equal to w 

 multiplied by a b (this line a b being supposed horizontal), together 

 with the moment of the beam. But P multiplied by the distance 

 of the zero division from a, is equal to the moment of the beam, 

 as already proved ; therefore it follows that P multiplied by its 

 distance from the zero division is equal to w multiplied by a 6. 

 Now, in order to graduate, let us suppose P one pound and w 

 seven. Then we have in numbers seven times a b equal once 

 the distance of the counterpoise from o, which tells us the exact 

 position of P for 7 pounds on the hook, namely, that yon find it by 

 measuring from o to the left seven pieces each equal to a 6. 

 Let w be 13 pounds or 3 pounds, then in like manner you 

 measure 13 or 3 pieces equal to a b. It thus appears that the 

 subdivisions for the successive pounds are equal to each other ; 

 and we may therefore lay down the following rule for graduating 

 a steelyard : 



Find first the zoro subdivision by bringing the unloaded in- 

 strument into an horizontal position by the counterpoise. Put 

 then on the hook, or in the pan, such a number of even pounds 

 as will push the counterpoise to the greatest distance it can go 

 on its arm for even pounds, aud divide the distance between this 

 last position and the zero point into as many equal parts a* 

 there are then pounds on the hook. The points of division so 

 obtained are the positions of the counterpoise for the several 

 pounds up to that number. 



For half and quarter pounds these divisions must be sub- 

 divided ; and for greater weights than one pound will balance 

 on the long arm, the counterpoise must be doubled or trebled, 

 etc. If the steelyard be intended for weighing small objects, 

 such as letters, tho counterpoise may bo ounces, or tenths of 

 au ounce, or even smaller weights, as occasion requires. 



* 



