« 前へ次へ »
tion to t; join t w, and we have the other or downward side of
NOTES. the roof; the lines x and y of the roof (in the building itself) are (a) From entreprendro.
(e) N'osa, dared not. parallel to st, and have the same VP, namely, vp3.
() M'éloigner, leaving the neigh (1) From faire. Our next problems will have especial reference to two inclina bourhood.
(9) From pouvoir, tions, and will require very close attention.
(c) Je me suis égaré, I lost my (h) From parastre.
(0) From the same verb.
(d) The il is unipersonal; it. () From revoir.
Après les premiers épanchements, Fodora raconta à son tour
l'espèce de succession de miraclesauxquels elle devait (a) son "Je suis,” dit-il, “un commerçant de Moscou ;? j'avais entrepris salut. La bonne vivandière ne fut point oubliée ? dans ce récit : (a) un voyage à Varsovie. Avant de m'éloigner (6), j'ai voulu aller mais avec quelle sensibilité, quelle touchante expression de revisiter un gentilhomme que je connais, et qui demeure à quelque connaissance, elle exposa tout ce qu'elle devait à la bienveil
. distance; armé d'un fusil, je me suis rendu à pied 3 à son lance da seigneur polonais qui l'avait recueillie et traitée id; châtean, où je me suis attardé. La neige tombait à gros flocons, comme son enfant. je me suis (c) égaré ;4 je cherchais en vain ma route, quand je vis
Au bout de quelques jours, la blessure du père de Fædon venir à moi deux hommes à qui je m'empressai de demander était guérie. Il dut (c) quitter le château de Polowski, et quelques renseignements. Je n'avais aucune défiance, et j'atten- Fedora le suivit, non sans assurer à ses bienfaiteurs que sa redais tranquillement leur réponse, quand tout à coup ces deux connaissance ne s'éteindrait qu'avec sa vie. scélérats, se précipitant sur moi,e me terrassèrent et me dépouil.
Ils revinrent(d) à Moscou, où leur retour causa une joyeuse lèrent du peu d'argent que j'avais. Je poussai un cri; c'est surprise. L'histoire de Fodora se répandit (e). Un jenne alors que l'un d'eux tira sur moi un coup de pistolet, car ils seigneur russe, qui occupait un haut grade dans les rangs de voulaient me tuer.”
l'armée, demanda la jeune fille en mariage et l'épousa. Pendant le récit de l'étranger, Fædora avait eu l'æil constam
Dix ans s'étaient écoulés. La Pologne avait proclamé son ment fixé sur lui. Il(d) lui semblait retrouver sur son visage indépendance, et l'empereur de toutes les Russies, Nicolas, mit des traits connus, sans se rappeler où elle l'avait vu; toutefois, une armée en campagne 1o pour comprimer les efforts de cette son cœur battait avec violence, un sentimento irrésistible l'at- héroïque nation. On sait (f) l'issue de cette lutte inégale. tirait vers lui. Polowski pria son hôte de lui donner quelques L'époux de Fedora avait pris part à la campagne;"' Fædora détails" sur l'incendie de Moscou.
l'avait suivi. Sans nous arrêter à rappeler les scènes déchirantes L'étranger parut éprouver quelque répugnance 12 à satisfaire à de cette guerre, nous dirons seulement que Varsovie venait d'être cette demande ; néanmoins, en réfléchissant au service qu'il emporté d'assaut."? Dans ce jour néfaste, des milliers de Poloavait reçu, il n'osa (e) refuser. En décrivant le triste spectacle nais et de Russes périrent.1 Vers le soir, tous les officiers de ce vaste incendie, sa voix trahissait de vives émotions.13 supérieurs de l'armée triomphante allèrent visiter le champ de Mais quand il commença à raconter ses propres malheurs, il bataille," où gisaient (g) pêle-mêle les cadavres des vainqueurs versa des larmes abondantes ; et poussant un profond soupir, et des vaincus. il dit :
Là, gémissaient confondus parmi les morts, un nombre infini “ Hélas ! ce terrible incendie ne m'a pas seulement enlevé une de blessés.15 Poussé par la charité, ému de compassion pour le grande partie de ma fortune, 15 mais encore ce qui faisait (f) tout destin de ceux à qui la fortune avait été contraire, l'époux de notre bonheur, ma fille bien-aimée. Tandis qu'au milieu du Fodora fit transporter dans les hôpitaux et les ambulances, 16 désordre affreux excité par l'épouvantable catastrophe, nous ceux à qui il restait encore un souffle de vie. Après ces soins cherchions, ma femme et moi, 16°à soustraire à la voracité des pieux, il allait s'éloigner de ce lieu de désolation, lorsque parmi flammes nos objets les plus précieux, nous perdimes notre enfant, plusieurs cadavres qu'on allait recouvrir de terre, il aperçut nn alors dans sa sixième année; sa bonne l'avait prise avec elle afin officier polonais de haut rang li et tout chamarré de crois et de de la conduire dans la maison d'un amil? qui demeurait dans décorations. Il crut remarquer en lui quelques signes de vie," et une rue écartée, où le feu ne sévissait pas encore. Mais ni la le fit transporter dans la maison 19 même où était Fædora. LA bonne ni l'enfant n'ont reparu, et depuis cet événement, 18 toutes tous les soins nécessaires lui furent prodigués ; 20 et, peu à pei, nos informations ont été stériles. Probablement, quelque édi- sortant de sa léthargie, l'officier polonais rouvrit les yeux. fice, en croulant, les aura englouties sous ses décombres."
Fædora était assise (h) au chevet de son lit.21 Tout à coup À ces mots Fædora, qui avait écouté avidement toutes les elle poussa un cri, elle avait reconnu Polowski. particularités de ce récit, ne put (9) contenir davantage les
Polowski, rétabli de ses blessures, n'avait échappé à un péril, émotions 19 qu'il avait excitées en elle. Elle se précipita au que pour retomber dans un danger plus terrible encore. 22 Son cou de l'étranger, en s'écriant
nom fut porté sur la liste des proscrits.23 Quand Fædora l'ap30 mon père ! mon père !"
prit, elle se rendit immédiatement près de l'empereur ;*: elle Ce fut un spectacle touchant. On nous pardonnera de ne embrassa ses genoux, et demanda sa grâce, et Nicolas attendri, point chercher à peindre la joie et la félicité dont leurs cours prononça le pardon de Polowski. étaient inondés. La plume est impuissante 20 en face de tels
COLLOQUIAL EXERCISE. tableaux. Que nos jeunes lecteurs se mettant à la place de 1. Que raconta Fodora ? 14. Que firent les officiers suré. Fædora ainsi que de son père.
2. Parla-t-elle de la vivandière ? rieurs? COLLOQUIAL EXERCISE.
3. De quelle manière parla-t-elle 15. Que voyait-on sur le champ de des bienfaits de Polowski ?
bataille ? 1. Comment le Moscovite com- | 12. L'étranger parut-il(i) satisfaire mença-t-il son récit ?
volontiers à cette demande ?
4. Le père de Fedora fut-il long.' 16. Que fit l'époux de Fædora ? 2. Qui avait-il voulu visiter ? 13. Paraissait-il ému durant son
temps malade ?
17. Qu'aperçut-il parmi les ca
davres ? 3. De quelle manière s'était-il
5. Partit-il bientôt ?
récit ? rendu au château du gentil. 14. Que fit-il en racontant ses mal
6. Que fit Fædora à son départ ? 18. Que crut-il voir en lui? homme ?
7. Où allèrent le négociant et sa 19. Que fit-il du pauvre blessé ?
heurs ? 4. S'était-il égaré ?
fille ? 15. Que lui avait enlevé l'incen
20. Comment fut-il traité dans ? 5. Que vit-il venir vers lui ?
demeure de Fedora ? die?
8. Qui épousa Fædora ? 6. Que firent les deux hommes ? 16. Que faisaient lui et sa femme
9. Que se passait-il dix ans plus 21. Où était Fædora, et que fit
elle? 7. Que fit l'un des voleurs après au milieu du désordre? que le commerçant eut poussé 17. Où avaient-ils envoyé leur pe
10. Que fit l'empereur Nicolas ? 22. Polowski était-il en sûreté un cri?
tite fille ?
23. Quel nouveau danger le mene8. Fedora était-elle attentive au 18. Avaient-ils revu(j) depuis, in 13. Qu'était-il arrivé à Varsovie ? récit de l'étranger?
bonne et l'enfant ?
13. Qu'arriva-t-il dans ce jour çait alors ? 9. Paraissait-elle (h) le recon- 19. Que fit Fodora en entendant
24. Que fit alors sa fille adoptive ? naître ?
ce récit ? 10. Quel sentiment éprouvait-elle 20. Pourquoi l'anteur ne décrit-il | (a) From devoir.
(6) Se répandit, became known. en l'entendant ? pas ce qui se passa entre le (6) Traitée, cared for.
() From savoir. 11. Quelle demande Polowski fit-11 père et la fille ?
(c) From devoir.
(9) From gésir. à son hôte ?
(d) From revenir.
(h) Assise, seated; from asseoir.
KEY TO EXERCISES IN LESSONS IN FRENCH,
to retire ? 23. It is time that you go to bed, 24. Must I riso ? EXERCISE 136 (Vol. II., page 298).
You must rise. 1. M. votre frère a-t-il pris garde de gåter son chapeau ? 2. Il a
EXERCISE 140 (Vol. II., page 331). pris garde de le gåter, il n'en a qu'un. 3. Allez parler à Mlle. votre 1. Que faut-il que notre ami fasse ? 2. Il faut qu'il reste chez nons seur, elle vous appelle. 4. Ne voulez-vous pas prendre une tasse de jusqu'à mon arrivée. 3. Que faut-il que notre voisin fasse ? 4. Il faut thé ? 5. Je viens de prendre le thé. 6. Qu'avez-vous dit à votre qu'il mette ordre à ses affaires. 5. N'est-il pas juste que vous payiez petite fille? 7. Je lui ai dit de prendre garde de déchirer sa robe. 8. vos créanciers ? 6. Il est juste que je les paie. 7. Est-il temps que Prenons garde de déchirer ce livre. 9. Mon fils vient de l'apporter. i votre petit garçon aille à l'école ? 8. Il est temps qu'il aille à l'école, 10. A-t-il pris le thé? 11. Il n'a pas encore pris le thé, il est trop tôt.
il est dix heures. 9. Faut-il que j'écrive à votre correspondant 12. À quelle heure prenez-vous le thé chez vous. 13. Nous prenons le aujourd'hui ou demain ? 10. Il faut que vous lui écriviez demain thé à six heures. 14. Prenez-vous du thé ou du café à votre dejeuner ? matin. 11. N'est-il pas fâcheux que votre frère ait déchiré sa cas15. Nous prenons du café. 16. Votre courrier a-t-il pris les devants ? quette? 12. Il est fâcheux qu'il l'ait déchirée. 13. Faut-il que Mme. 17. Il n'a pu prendre les devants. 18. Quel parti avez-vous pris? 19.
votre mère finisse sa lettre ? 14. Il n'est pas nécessaire qu'elle la J'ai pris le parti d'étudier ma leçon. 20. Avez-vous pris garde de finisse. 15. Est-il certain que M. votre fils ait oublié son argent ? 16. déchirer vos livres ? 21. J'ai pris garde de les tacher, 22. Quel parti Il est certain qu'il l'a oublié. 17. Il n'est nullement certain qu'il l'ait Fotre frère a-t-il pris ? 23. Il a pris le parti de se taire. 24. Avez- oublié. 18. Faut-il que vous fournissiez de l'argent à cet artisan ? 19. vons pris mon parti ? 25. J'ai pris le parti de mon frère. 26. Avez Il faut que je lui en fournisse, il n'en a pas. 20. Quoique vous fassiez, vous raison de prendre son parti? 27. J'ai raison de prendre son
vous ne réussirez pas. 21. Quoique dise M. votre frère personne parti, parcequ'il a raison. 28. N'avez-vous pas peur de prendre son
ne le croira. 22. Faut-il que je vous écrive ? 23. Il faut que vous parti? 29. Je n'ai pas peur de prendre son parti. 30. Prendrez-vous m'écriviez. 24. Désirez-vous que je sois malade ? 25. Je ne désire pas le parti de votre scur ou le mien ? 31. Je prendrai le parti de ma
que vous tombiez malade. 26. Exigez-vous que je vous dise cela ? 27. scar. 39. Allez lire votre livre, vous ne savez pas votre leçon. 33. Je
Il faut que vous me disiez tout. 28. Désirez-vous que j'aille chez rais ma leçon, et je sais aussi que vous êtes mon ami. 34. Allons vous ? 29. Je désire que vous y alliez. 30. Faut-il que je me lève ? trouver notre père, il a besoin de nous.
31. Il faut que vous vous leviez à l'instant. 32. Faut-il que M. votre
frère se couche ? 33. Il faut qu'il se couche à l'instant. 34. Il est EXERCISE 137 (Vol. II., page 330).
temps qu'il se couche, il est minuit. 1. That do you wish us to do? 2. I wish you to pay attention to your studies. 3. Do you not fear that the rain may prevent your
EXERCISE 141 (Vol. II.,
page 365). got out? 4. We fear very much lest the rain may prevent us from 1. Do you think that this cloth will last long? 2. I think that it fuilling our engagements. 5. Do you doubt his being at home now? will wear well, for it is strong. 3. Do you think that our porter will 6. I doubt his being there, it is already ten. 7. Do you require him be long coming back? 4. I think that he will not tarry. 5. Do you to set out early? 8. I am astonished that he is not yet gone. 9. Do wish us to stand ? 6. On the contrary, I wish you to sit down. 7. you prefer that I return these bracelets to you? 10. I prefer that you Do you believe that those students can learn five pages by heart in two pay me for them. 11. Does your neighbour fear lest his child may go hours ? 8. I believe that it is impossible. 9. Do you hope that our ont? 12, He fears lest he fall in the street. 13. Do you not wish friend may come early ? 10. I hope that he will arrive soon. 11. What that your pupils may obey you ? 14. I wish them to obey me, and to kind of a decanter must you have ? 12. I want one which holds a obey their professors. 15. Do you not fear lest that mechanic be ill ? litre. 13. I have a crystal one which holds two litres. 14. Do you 16. I fear his being ill, for his workshop is very unhealthy, 17. Do think that that merchant grows rich at your expense ? 15. I know you not regret his being obliged to work ? 18. I regret his being that he grows rich at the expense of others. 16. What parasol do you obliged to labour above his strength. 19. Do you not wish that he be think of lending me ? 17. I think of lending you the best I have. 18. acquainted with this news ? 25. I wish him to be told of it as soon as Will the tanner succeed in earning a living ? 19. I do not think that possible. 21. Does not your father wish you to buy a warehouse ? 22. he will succeed. 20. Do you think that this money will suffice for your He wishes me to buy a saw-mill. 23. Do you wish me to leave you ? 24. father ? 21. I think that it will be sufficient for him. 22. Do you I wish you to remain with me. 25. I wish you to start this morning. believe that those gentlemen depend upon me? 23. I know that they EXERCISE 138 (Vol. II., page 330).
depend upon you. 24. Do you think that the concert will take place 1. Voulez-vous que je parle à l'artisan ? 2. Je désire que vous lui to-day ? 25. I think that it will not take place. disiez de venir ici demain matin. 3. Que voulez-vous que je fasse ? 4. Je désire que vous m'apportiez un livre. 5. Ne désirez-vous pas que je lise votre lettre ? 6. Je désire que vous la lisiez et que vous la
POPULAR EDUCATOR CLASSES. donniez à mes soeurs. 7. Mlle. votre sæur ne craint-elle pas que la It is with much pleasure that we recur to the subject of these pluie ne l'empêche de sortir ? 8. Elle craint que la pluie ne nous empêche de sortir. 9. Doutez-vous que. M. votre père soit à la maison classes, and place before our readers a communication from the à présent? 10. Je doute qu'il y soit. 11. Exigez-vous que je fasse Promoter of the POPULAR EDUCATOR CLASS established at non travail à présent? 12. Je désire que vous fassiez votre travail BRISTOL, which, in addition to presenting an example of the avant de sortir. 13. Ne regrettez-vous pas que vous soyez obligé de general interest awakened by the paper which appeared in Part travailler ? 14. Je ne regrette pas d'être obligé de travailler. 15. XIII. (Vol. II., p. 411), affords a notable instance of the success Y'ates-vous pas étonné qu'il le sache? 16. Je suis étonné qu'il sache which has attended the movement in that city, and of the comtout. 17. Exigez-vous que je le paie aujourd'hui ?. 18. Je désire que parative facility with which the result was secured. The vous le payiez demain. 19. Que voulez-vous que je fasse ? 20. Je veux statement, as conveyed to us by this energetic student,* is so que vous le payiez immédiatement. 21, Craignez-vous que le maître emphatically practical in all its details that we venture to print voulez-vous que je dise ? 24. Je veux que vous disiez la vérité. 25. M. it without further comment. votre père ne désire-t-il pas que vous achetiez une maison ? 26. Il dé
He addresses us as follows:sire que j'achète un magasin. 27. Désirez-vous que nous vous quittions ? Being convinced that the publication in your pages of the 9. Je désire que vous partiez demain. 29. Voulez-vous que je reste result of our efforts to establish a POPULAR EDUCATOR CLASS, avec vous ? 30. Je désire que vous restiez ici.
31. Désirez-vous que can hardly fail to give an impetus to the establishment of similar je lui dise cette pouvelle ? 32. Je désire que vous la lui disiez. 33. Désirez-vous que vos enfants obéissent à leur instituteur ?
classes in various parts of the country, I have ventured to send
34. Je dé. sire qu'ils lui obéissent.
you a curtailed account of the movement in this city; and hope EXERCISE 139 (Vol. II., page 331).
that, by laying before your readers the facility with which we
have established these classes, the enthusiasm with which they 1. What must I say? 2. You must say what you have heard. 3. have been hailed, and the success with which they have been Is it not necessary that I finish that history? 4. It is not necessary attended, they will be induced to take aetion, and show their for you to finish it. 5. Is it not proper for me to satisfy my creditors ? 6. It is proper that you do it. 7. Is it not right that I pay you what readiness to follow a good example. I have borrowed from you? 8. It is right that you pay it to me. 9.
* Our first care was to provide a suitable meeting room ; Can it be that your brother has forgotten his family? 10. It cannot which done, we wrote to the Publishers for a large number of be that he has forgotten it. 11. Is it certain that your brother has circulars and window-bills, with which we were promptly supforgotten himself to such a degree? 12. It is certain that he has forgotten himself. 13. It is very sad that he has forgotten himself so. This gentleman has kindly given us permission to put in direct 14. Will you remain until I have put my affairs in order? 15. I shall communication with him any of our students who may desire to remain until you have regulated them. 16. Will it not be necessary address him
upon the subject of his successful efforts in the promotion for me to furnish that family with provisions ? 17. It will be neces. of the BRISTOL CLASS. He will be happy to furnish any further inforsary for you to furnish them, provided you have them. 18. Will it not mation that may tend to facilitate the establishment of these classes be better that you lend him money,
than let him want for necessaries ? in other towns. Any letters of request reaching us, asking for the 19. It will be better that we lend him some. 20. What must we do? mme and address of the “Promoter of the Bristol POPULAR EDUCATOR 21. You must carry this linen to my house. 22. Is it not time for me CLASSES," will receive immediate attention.
plied. We thus called together and held our two preliminary “First, the affairs of the society are regulated by a committee meetings, which were attended by about 45 and 120 young men of management, consisting of five officers, viz. : president, vicerespectively. At these meetings the whole of our arrangements president, secretary, treasurer, and librarian, and four members were completed, and it was determined to open the classes. The chosen by the classes. To these the management of the classes preliminary business consisted of
is left, with power to effect any changes which, in their judg. *1st. The proposition of the rules.
ment, might tend to increase their success and development. “2nd. The election of the officers.
"Being unable to obtain the use of the room in which we are " 3rd. The choosing of the subjects.
now holding our meetings oftener than one evening per week, we " 4th. General arrangements.
are compelled to confine ourselves for the present to the study of " Through the assistance of Messrs. Cassell, Petter, and French, English, and Shorthand; and we have had but comparaGalpin, to whom on behalf of the classes we beg to tender tively little difficulty in obtaining the gratuitous services of very our sincerest thanks, these preliminary meetings were held with accomplished masters, or leaders, in these several departments. out a farthing expense beyond the rent of a meeting room. Their method is simple, yet most effective. For instance, take The classes have excited the deepest interest in every part of Lessons in English, No. II. Here the leader would require from the city, and when we announce that 150 names are already on the members of his class answers to his questions respecting the books, we feel that it would be superfluous to add anything every part of that lesson. Where the inaccuracy of the replies as to their entire success.
indicated a haziness of conception, he would first point out the “The following is a copy of the rules which we have adopted mistakes, and then, by means of a black-board, illustrate the in our POPULAR EDUCATOR CLASSES :
precise meaning and mode of application of all the terms em“RULES
ployed. It is positively astonishing how small a portion of time
this occupies, and our English leader highly eulogised the "1. That the subjects treated on shall be those embraced by the admirable manner in which the lessons are presented, and new edition of CASSELL'S POPULAR EDUCATOR, and be con considers them specially adapted for the conducting of such ducted on the principles explained in Part XII., page 411, of classes. that work.
"In the French class there are about a hundred members, and “2. That the affairs of the Society shall be regulated by the it may at first sight appear incredible that any master should following officers (to be eligible for re-election every six months), be able to conduct successfully so large a class together. It is, viz. :-President, Vice-president, Secretary, Treasurer, and four however, not only practicable, but even simple. Take Lesson Members of the Classes, the whole constituting a Committee of II. in Part I. of the new series of this work; it contains several Management.
matters of importance. Our French master takes that lesson, "3. That the subjects for study shall be chosen by the votes of and touches, as they appear in order, upon every point. The the Members from those treated on in the work alluded to in difficulties, as fast as they appear, by his judicious mode of Rule 1.
teaching, vanish. Should any members be in doubt on any “ 4. That during the space of time allotted to each subject, the point they mention it, and are immediately put right. AfterMembers belonging to the respective Classes shall analyse and wards follow the exercises. Each in turn pronounces one of the review that portion which may have been appointed for study in sentences, and it will be readily understood that the master's the interim between the Meetings, submitting any difficulties to continual corrections and repetitions constitute a really good the respective leaders.
lesson in French pronunciation. He then appoints, for home * 5. That no Member shall make any proposition to the Classes, work, the lesson for the following week, including two English having reference to its management or mode of procedure, unless exercises to be translated into French, and two French exercises he shall have previously intimated to the Committee of Manage- into English. The members deliver these exercises to the French ment the nature of such proposition, and obtained their sanction master enclosed in cloth envelopes, with which they are supto bring it before the Classes.
plied for the purpose, and receive them back corrected on the “6. That the Committee be empowered to introduce any changes following meeting night. Thus four exercises are mastered in the management of the Classes which may be in their judg. weekly-a by no means tardy pace. The signatures of the ment conducive to their increased success and development; élèves are attached to the exercises, and the leader is thus such changes including the introduction of new subjects, the enabled to keep a record of the mistakes, which he does, the removal of the Society's Meeting Room or Rooms, and any object of which is to create a spirit of emulation among them. changes which shall be found expedient.
Taken as a whole, the French class is, in our opinion, conducted " 7. That every Member shall be a Subscriber to the new series in a most satisfactory manner. of CASSELL'S POPULAR EDUCATOR, and that those who shall, "In the Shorthand class we have upwards of a hundred memsubsequently to the printing of these Rules, join the Classes, and bers. It is, indeed, a most popular subject. In conducting who do not subscribe to that serial, shall immediately become this class we have experienced no difficulty whatever. It would subscribers, and further, shall obtain such back parts as the be almost as easy to instruct a class of 500 as one of twenty carrying on of the business of the classes shall render it neces- members. The lessons in Phonographic Shorthand, as comsary to obtain.
menced in Part XIII., are explained and illustrated by means of "8. That this Society engage no paid teachers, and be carried a black-board; and having been so fortunate as to secure the on without any expenses beyond the rent of a Meeting Room, services of a most proficient master, we are getting on very and other unavoidable incidental expenses.
satisfactorily indeed. "9. That the Committee reserve to themselves the right of dis “This is something of our present position. We are increasing crimination, and be empowered to disallow any of doubtful very rapidly. The members thoroughly appreciate the value of character to join the Classes, or any person who in their judg. the service rendered them; they are, in fact, enthusiastically in ment might prove in any way detrimental to their progress. earnest. As soon as we can manage to meet twice instead of
“10. That any Member conducting himself in an officious or in (as at present) once weekly, we purpose introducing other suban improper manner, in any way becoming obnoxious to those jects, especially those of Latin, German, and Bookkeeping-for present, or not conforming to the whole of the Rules of the two of which subjects leaders have already volunteered. As a Society, be expelled from the Classes.
text-book we confine ourselves strictly to the POPULAR EDU“11. That the name of any Member absenting himself during Cator, and experience justifies us in recommending similar the whole of three months, without legitimate and specified classes in this particular, if in no other, carefully to follow our cause, shall be erased from the list of Members.
example. In no work that we have yet seen are the subjects “12. That the Committee be empowered to alter either or the treated on with such completeness and such admirable clarté, or whole of the foregoing Rules, or to create additional Rules, or so calculated to ensure the object of the learner-SUCCESS. to effect any changes which may prove essential to the increased * In conclusion, allow me to add that it will be a matter of success of the Society.
surprise to me if, in the course of a little time, POPULAR EDU
CATOR CLASSES, on the principle laid down in your work, do “We are now in full working order ; and as it may be useful not become truly national, both as regards their extent and to many of your readers, I will endeavour very concisely to ex. character, and be established in all or nearly all the great towns plain our mode of conducting the classes.
and boroughs of the United Kingdom."
temperature of the air havo also been taken, but no important
practical results have as yet been achieved. GAS BALLOON-PRESSURE OF THE AIR-MAGDEBURG HZMI.
Having now seen proofs that the air has weight, we must see SPHERES-SUCKER-SPILE-PEG-SYPHON.
what effects this weight produces. If we lay a piece of iron or We saw in our last lesson that air, when heated, becomes su.. any substance on our hand it produces pressure, the amount of ciently rarefied to raise a balloon, together with its car and which varies with the weight of the body, and we should naturally several passengers, but that there is great danger from fire. expect the same effect to be produced by the air. A few simple Now it was found that hydrogen gas was lighter than heated experiments will show us that this is actually the case, and that air, and hence it soon began to be used for inflating balloons, the air does exert a very great pressure on every substance exwhich were found to possess great lifting power. Pure hydrogen posed to it. This pressure amounts to nearly 15 pounds on every has less than lith the weight of common air, 100
square inch of surface. If we have a card meacubic inches of it weighing only about 2.14
suring 4 inches by 3 inches, the pressure on it grains. If, then, a balloon having a capacity of
from the air will be 180 pounds. But it will be 16,000 cubic feet be filled with this, it will pos
said this pressure is not felt, nor does the card sess a lifting power of about half a ton. The
bend at all; why is this ? Simply because the hydrogen used was at first commonly made by
pressure is equal in all directions, and therefore the action of sulphuric acid and water on pieces
that on the lower side balances that on the of iron or zinc, the gas given off being passed
upper. If we take away the air from the under through water to wash it from the acid, which
side, we shall soon find that this is the case. would injure the balloon. It was, however, found
This may easily be done by means of the airto be expensive thus to make it, and being so
pump. We have only to procure a glass receiver, light it soon mixed with the air, and thus lost
open at each end, and having stretched a piece much of its buoyancy; common coal gas is there
of bladder or of thin india-rubber over one end, fore dow generally used, and if it be made at a
place it on the pump-platė, and exhaust the air somewhat higher temperature than usual it is
(Fig. 3). The pressure above, not being balanced sufficiently light for most purposes. Its specific
any longer by a corresponding pressure on the gravity is much less, indeed, than that of pure hy.
under side, will press the bladder down, and, drogen, being about one-half that of the air, but
after a few strokes, cause it to burst with a loud increased size in the balloon will compensate for
report. A thin piece of glass, if it be flat this, and it has the advantages of being cheap,
enough to close the top of the receiver air-tight, easily procurable, and more manageable.
may be broken in a similar way, and thus will As the balloon ascends the pressure of the air becomes less give a further proof of the intensity of the pressure. and less, and thus the gas in it expands, and would soon burst Instead of the bladder or glass the hand may be laid on the open the silk, were it not that a large aperture is always left at receiver, and will be pressed down forcibly as the air is removed. the neck of the balloon to allow of the escape of any excess. So The cupping-glass, formerly so much used, acted on this prinsensitive is this large body of gas to changes of pressure or tem-ciple. The air in it was rarefied either by means of a small perature, that the fact of passing from a cloud into the rays of the syringe, or by heating the glass and allowing it to cool when son makes a very perceptible change in its bulk.
placed over the required part of the body; the flesh was thus A number of sand-bags are usually suspended outside the car, drawn up, and then pierced by the lancets. and when the aëronaut wishes to ascend he empties some of If a wooden cup, with a piece of cane let into the middle of these, and thus diminishes the weight of the car and causes the it, be made to fit the top of the receiver and filled with mercury, balloon to shoot up rapidly. A large valve is also fixed at the the pressure of the air, when the receiver is exhausted, will drive top of the balloon, and can be opened by means of a cord which the mercury through the pores of the cane, and it will fall like a passes down into the car. When the tension
fine shower into a vessel placed to receive it. becomes very great, or the aëronaut wishes to
Care must, however, be taken not to let any of descend, he opens this, and thus allows a portion
it run into the pump, as it is almost certain to of the gas to escape. The greatest care is, how.
injure it seriously. ever, necessary in descending, as much of the gas
This pressure is exerted equally in all direcbas escaped, and when the balloon nears the earth
tions, and hence is almost unnoticed: a simple again it collapses to a considerable extent, and a
experiment, which all can try, affords å proof of further quantity of sand has to be let out. The
this. Fill a wine-glass with water, so that it greatest elevation ever yet attained in a balloon
stands a little above the edge, and carefully was on the 5th of September, 1862, when Messrs.
slide a piece of card over the mouth so as to Coxwell and Gleisher made an ascent from Wol.
cover it completely and exclude the air; the verhampton for the purpose of making some scien
whole may now be inverted without the card tific experiments, and on this occasion a height
falling or the water being spilled. The sides of of upwards of six miles was reached. Mr. Glaisher
the wine-glass sustain the downward pressure of at this height became unconscious, and Mr. Cox.
the air, and the upward pressure is more than well had not strength enough left in his hand to
sufficient to sustain the weight of the water in open the valve, but was fortunately able to pull
the glass. The only advantage of the card here the string with his teeth, and thus to descend.
is that it prevents the surface being broken up, At this time two-thirds of the atmosphere was
and thus allowing the air to enter at places. A beneath them, and the barometer stood at less
bottle with a very small mouth may be comthan ten inches.
pletely filled and carefully inverted without the A grapnel is usually suspended from the car,
water running out, even though the card be and catching the earth gives assistance in
not used. descending ; but with every care a violent
Several conjuring tricks are performed upon this shock will frequently be experienced, and the scientific instru- | principle, and many others are only ingenious applications of scienments taken in the car be broken. A parachute is sometimes tific principles, and appear startling mainly because these princitaken up with the balloon. This consists of a large circular ples are so little understood by the majority of men. If a small piece of canvas with a small car suspended by ropes fixed at hole be drilled in the bottom of a decanter, and the stopper put intervals round its edge. If the aëronaut gets into this, the in firmly, no liquid will escape. The finger must, of course, bo canvas will open out like an umbrella, and the resistance of the held over the opening while the liquid is being poured in. The air against it will be sufficient to break the force of the fall. decanter is then placed over a stand large enough to contain the At present no very great results have been obtained by the use wine, and on the stopper being slightly loosened the liquid will
In war one has occasionally been sent up quietly flow out. A cover is placed over it while this is going fastened to a long rope, and from this the position of the enemy on. În the same way liquids may be made to flow from small has been noted. Many valuable observations as to the state and reservoirs concealed in covers into glasses placed upon them, VOL. III.
of the balloon.
and thus the wine appears to have passed from the decanter into the glasses. We see, thus, that there is science to be learnt even from some of the tricks of the conjuror, and a person who understands the principle of these things will be less likely to be deceived. Perhaps the most striking proof of the pressure of the air is afforded by boiling some water in a thin cylinder provided with a stop-cock. After the water has been boiling for a little time all the air which was within is driven out, and it remains filled with steam. Let the stop-cock be now closed, and cold water poured over the cylinder; the steam inside will be instantaneously condensed into water, and the pressure of the air around will crumple up the cylinder, even though the cylindrical shape is best calculated to resist a pressure of this kind. If the steam inside a boiler be suddenly condensed by admitting cold water too rapidly, or in any other way, the boiler will sometimes collapse in a similar way. By ascertaining the area it exposes to the air, and multiplying the number of square inches in that by 14, we shall see how enormous the pressure thus exerted must be. Another piece of apparatus, known as the Magdeburg hemispheres (Fig. 4), furnishes a very good illustration of this pressure. Two hemispheres usually made of brass are procured and their edges accurately ground, so that, when pressed together, they fit air-tight. A handle is fixed to each, that on one being so arranged as to screw on the end of a pipe closed by a tap and opening into the hemisphere. This handleistaken off, and the hemispheres pressed together, a little tallow being smeared on their edges; the pipe is then screwed into the hole in the centre of the pumpplate, and the air removed. When sufficiently exhausted the tap is closed, the apparatus unscrewed from the pump, and the handle replaced. Nearly all the air has now been removed from within them, and that around, therefore, presses them together with great force. If the hemispheres have a diameter of four or five inches, this pressure will be so great that it will be as much as two men can do to pull them apart. If, however, the tap be opened and the air re-admitted, the pressure inside will balance that outside, and they will fall apart by their own weight. It will easily be seen that, if their diameter be five inches, the portion of the pressure of the air which forces them together will be equal to that on a circular surface of the same diameter. Now, as the area of a circle is about 3} times the square of its radius, the area of this surface would be nearly 20 square inches, and we may assume that the air inside is so far rarefied that they are pressed together with a force of 14 pounds per square inch : the force required to separate them is therefore nearly 280 pounds. A pair of hemispheres of this kind were constructed by Otto Guéricke, one of the inventors of the air-pump, of such a size that two teams of horses, pulling in opposite directions, were unable to separate them. The pressure of the air furnishes us with explanations of many of the common phenomena of every-day life. When a cask is tapped, the beer soon ceases to flow unless a small hole be bored at the top, just as in the magic decanter the wine refused to run out of the small hole at the bottom until the air was admitted by the loosening of the stopper. A well-made cask is perfectly air-tight, and as soon as a little of the beer has been drawn from it the air inside becomes rarefied; the pressure of the external air is therefore greater, and, acting on the liquid in the tap, prevents its flow. As soon, however, as air is admitted by the spile-peg, the pressure is equalised, and the beer flows evenly.
For the same reason a small hole is usually made in the lid of a
teapot, so that when the water standing round the lid makes it nearly air-tight the tea may still flow in an even stream. If we invert a wine-bottle, the liquid will flow out in a very irregular way; the air has to pass in by the neck at the same time as the contents flow out, and the meeting of the two produces the well-known gurgling sound. If, however, the bottle be slightly inclined, so that the air may enter at the upper part of the neck while the liquid flows out at the lower part, all this gurgling is avoided, and the liquid flows better and more
dly, "or, another illustration of the pressure of the air in the - ker, so well known to every boy. A piece of string, at the end of it, is passed through the centre of a of thick leather, which has been soaked in water neiguite soft and pliable. It is then pressed
closely down on a stone or flat surface so as to exclude the air from under it, and will be found to adhere so firmly that the stone may be raised by the string without its leaving the leather. The reason of this is that the moisture prevents the air entering between the stone and the leather. When, therefore, the leather is raised in the middle by the string a partial vacuum is produced, and the pressure which the air exerted on the upper surface of the stone is transferred to the leather and balanced by the tension of the string. The pressure of the air on the under side of the stone, being no longer balanced by a corresponding pressure above, lifts the stone. It is frequently required to draw a small quantity of wine from a cask, as a sample, without tapping it: a small instrument known as a wine-taster is therefore made use of. This consists of a hollow tubular vessel, having a small aperture at each end, and somewhat bulged in the middle, as shown in Fig. 5. The bung is removed from the cask and the taster inserted. The wine soon rises through the opening at the lower end till it finds its level, the thumb is then placed over the opening above, and the air being thus prevented from entering, the wine is retained, and can be removed from the cask without any loss. On the thumb being removed from above air will enter, and the liquid will flow out into a glass. Bird-cage fountains also depend for their action on the pressure of the air. The reservoir is constructed so as to be air-tight, and a small trough is placed near the lower end from which the birds may drink. This communicates with the reservoir by a small hole made at the level at which it is desired to maintain the water. As soon as the water is so far removed from the trough that this hole is exposed, a bubble of air enters and displaces a small quantity of water, and in this way a uniform level is maintained and a constant supply of fresh water. Pneumatic inkstands have been constructed on a similar principle, the advantage resulting from their use being that a much less surface is exposed to the air, and therefore the ink does not thicken so rapidly, and also that there is less danger of spilling the contents. We must now pass on to notice avery useful piece of apparatus —the syphon. In many manufacturing processes, and in chemical experiments, a liquid is often allowed to settle, and the clear liquor above has to be drawn off without disturbing the sediment, as would be done if the vessel were tilted so as to pour out the liquid. This can easily be accomplished by means of the syphon, which consists merely of a tube bent into the shape of the letter U, one limb, however, being longer than the other. In Fig. 6, c is the vessel from which the water has to be drawn off, and C B represents the syphon. This is filled with water, and then, the ends being closed by the finger, inverted into the vessel; or it may be placed in the vessel, and the air exhausted from it by sucking with the mouth at the end B; the air being thus partly removed from the tube, the water rises and flows over the bend. The principle on which it acts is simply this: Let the syphon be full of water, and Fig. 6. let us imagine a layer of water across the highest point of the bend to become solid. Thi forces which act on this layer and force it towards c are thi pressure of the air acting upwards at B and the weight of column of water equal in height to D c, for it is clear that thi column has to be supported by the layer. The forces whic drive it in the other direction, or towards B, are the pressure q the air on the surface of the liquid in C, which pressure is tran mitted along the tube, and is just equal to the pressure at B, an the weight of a column of water equal in height to A. B. It wi thus be seen that the liquid will be moved along the syphont