LESSONS IN CHEMISTRY. 



mail j'ai pear t ommlL 18. Le Hollandses a-t-il plus do frontage 

 * las de fromuifo ct plus d'argont. : 



iut de sole anglaise que de soie iUlienne? 15. J'ui i>lu do 



. eellu-la. 16. Qui a plus d'amis qua 1'Knpuirn 

 i i-lu.s. i -. L'Eiipagnol a-t-il iiutaut de votre ar 

 !'. II a mom* du niiou que du lien. 20. Avons-iumi plun 



:iux de soio i| ! m.mUuiux de drop? 21. Nous avouu plus 

 i -IMC de oeux-14. 88. Avez-vous de bout mauteuu 



, j'.ii de bous inanteaux, de bans cbapeaax, et de bons 

 ! i-n.r. Jl. Avez-vou* plui d'assiettes que de plats ? 25. Je 



u'ui pas plus d'asaiettes que de plats, mais j'ai plus do vorres que 



a. 26. N'UTOZ-VOUS pas tres-f roid ? 27. Non, Monsieur, je 



..id ni ohaud. 128. Votro obarpontier a-t-il du bois ( 29. Oui, 



, il a du bois, do 1'urgeut, du fromage et de la viando. 30. 



(.jui .1 plus d'argeut que le cbarpeutier .' :i !. Hnlhui'lais en a davan- 

 :. (.''a a plus d'estampes que do livrea ? 33. Le libraire a plus 

 -ei que de cellos-la. 34. fitea-vous aussi attcntif que votre 



ami ? 35. Je suis plus attentif que mon ami. 



EXERCISE 27 (Vol. I., page 115). 



1. Is your dictionary Tory correct ? 2. It is more correct than 

 Boyer's. 3. Your dictionary is the most correct of all. 4. Which is 

 the most beautiful of those gardens ? 5. This is the most beautiful of 

 irdons of the city. 6. Hare you any more money ? 7. I have 

 no more money, but I have still some credit. 8. Have we more salad ? 

 9. We have no more. 10. We have no more meat. 11. Who has more ? 

 12. My brothers uml sisters have some more. 13. Have you much more ? 

 1 1 . 1 have not much more. 15. Has your aunt more dresses than 

 your uiece ? 16. She has not many. 17. Is your nephew more 

 loarned than your niece ? 18. He is not so learned as she. 19. She ia 

 jioro learned than he. 20. Are you still cold ? 21. I am no longer 

 cold, I am very warm. 22. Have you no more news ? 23. I have no 

 more. 24. Have you many? 25. I have but few. 



EXEBCISE 28 (Vol. I., page 115). 



1. Votre frere a-t-il un tres-bon dictionnaire ? 2. Son dictionnaire 

 n'est pas tres-correct. 3. Votre pore a-t-il plus de courage que lui ? 

 4. II a beaucoup plus de courage que votre neveu. 5. Vos freres out- 

 ils du credit ? 6. Us n'out guere de credit, mais Us ont de 1'argent. 

 7. Votre tauto cst-ello obligeaute ? 8. Ma tante est bien obligeante. 

 9. Avez-vous encore des livres, des plumes et du papier? 10. Je n'ai 

 plus de livres, mais j'ai encore de bonnes plumes et d' excellent papier 

 anglais. 11. Qui a encore du papier ? 12. Je n'en ai plus, mais inon 

 frere en a encore. 13. Avez-vous des nouvelles, Monsieur ? 14. Non, 

 Madame, je n'en ai pas aujourd'hui. 15. Avez-vous autant de bois 

 que le flls de mon frere ? 16. J'en ai plus que vous ou que lui. 17. 

 Avez-vous encore tort ? 18. Non, Monsieur, je n'ai plus tort, j'ai 

 roison. 19. Vos scaurs ont-elles encore faim ? 20. Elles u'out ni 

 faim ni soif, mais elles ont encore sommeil. 21. Votre niece est-elle 

 aussi savante qui lui ? 22. Elle est plus savante que lui et que sa 

 tante. 23. N'avez-vous pas de nouvelles, Monsieur ? 24. Non, 

 Madame, je n'ai plus de nouvelles. 25. Qui a des nouvelles ? 26. Je 

 n'en ai plus. 27. Les avez-vous toutes ? 28. Oui, Monsieur, je lea 

 ai toutes. 29. Votre tante en a-t-elle encore beaucoup ? 30. Elle 

 n'en a plus guore. 31. Votre frere a-t-il encore des chevaux anglais ? 

 32. II n'en a plus. 33. II en a encore deux. 34. Avez-vous encore un 

 beau chale fran^ais ? 35. Je n'ai plus de chiles franyais, mais j'en ai 

 eucoro uu anglais. 



EXERCISE 29 (Vol. I., page 116). 



1. How many potatoes has your brother ? 2. He has not many. 

 3. Has the grocer much sugar in his warehouse ? 4. He has but 

 little, but he has much butter and pepper. 5. Has your gardener 

 many cherries ? 6. He has more cherries than plums. 7. Are plums 

 better than cherries? 8. Cherries are better than plums. 9. Have 

 you a few ripe pears ? 10. We have a few, we have also many 

 pine-apples and apricots. 11. Has your uncle anything good in 

 his garden ? 12. He has something good and beautiful. 13. He hat 

 beautiful vegetables and beautiful flowers. 14. Have yon foreign 

 flowers ? 15. I have a few. 16. Which have you ? 17. I have your 

 brother's and your gardener's. 18. Have you not mine also ? 19. No, 

 Sir, I have them not. 20. Who has many ? 21. Nobody has many. 

 22. I have a few. 23. Have you tea enough ? 24. I have enough. 

 25. I have more than he. 



EXERCISE 30 (Vol. I., page 116). 



1. Votre jardinier o-t-il beaucoup de legumes ? 2. Oui, Monsieur, 

 il en a beaucoup. 3. Combien de jardins a-t-il ? 4. II a plusieurs 

 jardins et plusieurs maisons. 5. Avez-vous beaucoup de livres ? 6. 

 Je u'eu ai guere, mais mon ami en a beaucoup. 7. Quel habit votre 

 frere a-t-il? 8. II a un bon habit de drap. 9. Votre oncle a-t-il 

 beaucoup de peches ? 10. II n'a pas beaucoup de peches, mais il a 

 ijesiicoup de cerises. 11. Combien de prunes le tailleur a-t-il ? 12. 

 Lo tailleur n'a pas de prunes, il a du drap et de la sole. 13. Quelle 

 soie votre ami le marchand a-t-il ? 14. II a beaucoup de soio et beau- 

 coup d* argent. 15. Le jardinier a-t-il quelque chose de bon dans son 

 jardin ? 16. H a beaucoup d'ananas. 17. A-t-il plus de legumes qua 



de fruit? 18. II a plus de oenx-ci qu de cenx-U. 19.VotraoncUa-t.il 

 beaucoup de poire* et de eerines ? 20. II en quelques-unes, et il a 

 beaucoup de pommes et de prune*. 21. En avez-voos qtxlqnes nnes ? 

 22. J'en ai encore beaucoup, main mon frere n'en a plus. 23. Qnelles 

 pechos a-t-il ? 24. II a de grosses pebes. 25. Leoquelle* tvez-vous ? 

 26. J'ai les meilleures pucbes. 27. Le marcbaud a-t-il quelque chose 

 de bou dans son magasin ? 28. II n'a rien de boa dans on ""t^t* 1 ?, 

 mais 11 a quelquo chose de bon dans con jardin. 29. Combien d 

 pommes de terre IVtrauger a-t-il ? 30. II ti'en a pas beaiiooup. 

 31. A-t-il de bons legumes? 32. II a de bons legume*. 38. 

 A-t-il ruison ou tort ? 31. II a raison, main vou avez tort. 35. II 

 n'a ni ce livro-ci ui celul-la, il a celui du libraire. 



EXERCISE 31 (Vol. I., page 131). 



1. It the horse which you have good ? 2. It is better than that 

 which you have, and than that of our friend. 3. How many children 

 have you? 4. I have only one, but the Italian has more than I. 5. 

 Is it the tenth of September '{ 6. No, Sir, it IB the ninth of February. 

 7. Have you my silk cravat or my muslin cravat ? 8. I have both. 

 9. Have you eight kilogrammes of cinnamon ? 10. No, Sir, I have 

 only half a kilogramme. 11. How many francs have you. Sir ? 12. I 

 have only half a franc, but my friend has two francs. 13. Has your 

 sister twenty-five centimes ? 14. Yes, Sir, she has a quarter of a franc. 

 15. Is it not the first of August ? 16. No, Sir, it is the sixth of Sep- 

 tember. 17. Is to-day the tenth ? 18. No, Sir, it is the eleventh. 

 19. Has your brother the first place. 20. No, Sir, he has the tenth. 

 21. Has your joiner many tools? 22. Yes, Sir, he has many. 23. Has 

 that work ten volumes ? 24. No, Sir, it has only nine. 25. I have 

 the sixth volume of Moliere's works, and the first volume of Michelet's 

 History of France. 



LESSONS IN CHEMISTRY. VII. 



WATEE. 



SYMBOL. . H,O COMBUJIHO WXIBHT. 18 



As we have already seen, hydrogen, when it burns in air, enters 

 into combination with the oxygen, forming water. The moat 

 direct way of proving this is by means of the Eudiometer, an 

 instrument by which the composition of water is determined by 

 synthesis. 



A strong glass tube (Fig. 27) is hermetically sealed at one 

 end, and through the glass two platinum wires are thrust when 

 in its melted condition; these wires are opposite each other, 

 and almost meet. 



The tube is filled with mercury, and inverted into a bath of 

 the same metal. A mixture of the gases, in the proportion of 

 two volumes of hydrogen to one of oxygen, is passed into the 

 tube, until the greater part of the mercury is displaced. The 

 tube is now held firmly down with its mouth on a piece of sheet 

 india-rubber ; for if this were not done, when the gases explode 

 the mercury would be driven ont of the tube, and the experiment 

 rendered fruitless. A Leyden jar is charged with electricity, a 

 chain attached to one of the platinum wires is held against the 

 outside of the jar, whilst with the knob the other wire is touched. 

 The jar is thus discharged, a spark passing between the wires in 

 the tube and exploding the gas. Upon releasing the pressure of 

 the tube against the india-rubber, the mercury from the bath 

 rushes into the tube, completely filling it, leaving only a small 

 globule of water in the place of the tube full of gas. 



The composition of water by analysts is easily determined by 

 means of electricity. It is a well-known property of the gal- 

 vanic current that whenever it passes through water, the water 

 is decomposed. The hydrogen passes with the current, and 

 appears in bubbles at the negative wire, whilst the oxygen 

 comes off from the positive wire. Fig. 28 indicates the arrange- 

 ment for the experiment. 



The two test tubes and the vessel are filled with water, to 

 which is added one-eighth of sulphuric acid, to make the water 

 a conductor of electricity. The test tubes are now inverted 

 over the two leaves of platinum, h, n, which are connected with 

 the screws A and B. To A is attached a wire from the platinum 

 end of a Grove's battery, to B the wire from the zinc end. The 

 electric current in the battery is generally said to pass from 

 the zinc to the platinum; it leaves the battery by the wire 

 attached to the platinum, passes from the screw A through the 

 water to B, and back to the zinc end of the battery. Because 

 the current enters the instrument by the wire attached to A, that 

 is said to be the positive wire, the other being the negative. 



The gases as they rise from the plate are received in the- 

 tabes, and it will be found that the hydrogen is nearly twice the 



