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being k, the elongation corresponding to t degrees is t times k TABLE OF THE
or kt for a single unit, whence it is 1 times kt or ktl for I units CO-EFFICIENTS OF THE EXPANSION OF METALS
of length. The length of the bar which was l at 0° Centigrade, According to the Centigrade Scale.
is therefore 1 + ktl at t degrees ; whence ľ=+ ktl (1).
By putting i into the form of a common factor, we have l' = Metals.
1(1 + kt) (2). This formula will give the length l' at to when Platinum
the length lat 0° Centigrade is known. Glass
By dividing both members of the preceding equation by Soft steel 0.000010788
r Cast iron
(1 + kt), we have l= (3). This formula will give the Iron slightly hammered 0 000012204
1+ kt Tempered steel
length at 0° Centigrade when the length ľ' at t degrees is 0.000014660
By transposition in equation (1), and dividing both sides by Bronze
th, we have k" -? (4). This formula will determine the Silver, fine
0.000021730 co-efficient of linear dilatation k, when I, l', and t are given. Lead
Prob. 1. Given the length i' of a metallic bar at ť degrees, Zino
0 000029417 to find its length ?" at t" degrees. As this table is constructed for the Centigrade scale, it will
By formula (2) l=1(1 + kt), and I''=1(1 + k t'). From be useful to show how to adapt it to the scale used in this the former equation, 1 =
; substituting this value of country. By removing the decimal point in each of the num
1+kt bers of the table iwo places to the right, these numbers will then represent the whole amount of expansion which each bar in the latter equation, we have r" ='(1+kt"). of metal undergoes when heated from 0° to 1000 Centigrade,
1 + kľ or from 32° to 212° Fahrenheit. By dividing each of these Prob. 2. Given the density d of a body at 00 Centigrade, to numbers by 180 (the number of degrees from 32° to 212°), the I find its density d' at t degrees.
1 + kit
quotients will become the co-efficients of expansion according By denoting the volume of a body at 0o Centigrade by unity
, bar of metal will be elongated when its temperature has risen will be 1 + kt; but the density of a body is in the inverse
or 1, and its cubic expansion by k, the volume at t degrees by 1o Fahrenheit between the freezing and the boiling
points ratio of the volume which it takes on expansion, we have, of water. Thus, the co-efhcient of expansion for glass, by the
d Centigrade scale, is 0.000008613; therefore, glass expands
.; whence, d'= 0 0008613 of its length at oo Centigrade, when heated from
1+kt that point to 100° Centigrade, or from 32° to 212° Fahrenheit; All these formulæ and rules will apply to examples in now, dividing 0.0004613 by 180, we have 0 000004785 for the Fahrenheit's scale, il 32° Fahrenheit be put for 0 Centigrade, co-efficient of expansion, according to Fahrenheit's scale. As and t- 320 for t'; also, if the Table of the Co-efficients of it may be useful to many of sur readers, we give the Expansion according to Fahrenheit's scale, be used instead of
that accoruing to the Centigrade scale. TABLE OF THE CO-EFFICIENTS OF THE EXPANSION OF METALS
Examples. I. If a bar of iron be exactly twelve feet long at 0°
Centigrade, what will be its length at 60° Centigrade, the coAccording to rahrenheit's scale.
efficient of linear dilatation being 0 000012204 according to the
Centigrade scale :
Here, by formula (2), we have l = 12 (1 +0.000012204 X 80)
= 1201171584 feet, or twelve feet and of an inch nearly, Glass
, Soft steel
0.004005993 what will be its length at 176° Fahrenheit, the co-efficient of Cast iron
linear dilatation being 0.00000678 acccording to Fahrenheit's Iron, slightly hammered
scale ? Steel, tempered
Here, by formula (2), we have l =12 (1+ 0.00000678 X 0 000008144
144) =12.01171584 feet, or twelve feet and of an inch nearly, Copper
at 0° Centigrade, the co-efficient of Silver, fine
linear dilatation being 0.000017182 ? Tin
Here, by formula (3), we have l =
= 14.96685 feet, or 14 feet 114 inches nearly. on Expansions by the Scale.Let ? be the length of a sortir le voan Centigrade, lipid length at appredictions in the artisan The iron gratings of furnaces
, there the temperature't, and k its co-efficienti on linear esparition antanee, should het be too accurately fastened at their extent The elongation corresponding
to the eand
, sou helt free at one end at least ; otherwise they will
15 1 + 0.000017182 X 90
displace the stones of the fire-place by their expansion. If on metals has received an important application in the compensarailways the iron rails are in contact, the force of expansion tion pendulum. This name is given to a pendulum in which will make them either become curved, or will break the the elongation of the rod when the temperature is raised is chairs. When a glass vessel is heated or cooled too suddenly, compensated for in such a manner that the distance between
the centre of suspension and the centre of oscillation remains
constant, which is necessary according to the laws relating to
This app ratus operates as follows: when the temperature
Another method of compensating for the elongation of the pendulum rod, is by means of compensating laminæ or bars. It consists of two bars, one of brass and one of iron soldered together, and fixed to the rod of the pendulum, as shown in fig. 178. The bar of brass, which is more expansible than the bar of iron, is placed below it. When the temperature is lowered, the rod of the pendulum is shortened, and the bob rises; but then the compensating bars become curved, as shown in fig. 179, because the brass contracts by cold more than the iron. In this manner, two metallic balls placed at the extremities of the compound bar are lowered; and if they have been
properly adjusted, they establish a compensation between the it breaks in pieces ; because glass being a bad conductor of points which are nearer to the centre of suspension and those caloric, the sides of the vessel are irregularly heated, and con
which are farther from them, and thus the centre of oscillasequently expand unequally, which produces the 'disruption tion is not displaced. If the temperature is raised, the
bob descends; but the balls are raised, as shown in fig. 180, Compensation Pendulum.--The unequal expansion of different and compensation takes place by a similar operation.
of the parts.
oxide of manganese and common salt (about equal parts by LESSONS IN CHEMISTRY.–No. XXXII.. weight)—five or six table-spoonfuls will suffice for our wants We shall in this lesson enter upon the consideration of the bente tube have been securely adapted, add sufficient of a ealed on account of its yellowish green colour, xupos being to reduce the oxide
of manganese and salt to the
consistence eparately obtained, and under all ordinary circumstances, is a the prismatic trough as usual. A few preliminary
words og hveing condensed into the liquide forma anticondensation of ment of this gas will not here be out of place
. First of all, it opetus bodynevertheless it admits by particular treatment expressive of certain cautions to be observed in the develop
which we shall have to speak further on.
is not suficient merely to pour the dilute acid upon the man
* * * : Mix ngay 1 r - ck
er he well incorporated by shaking,
otherwise the flask will most probably break on the first appli- | the extent of the decomposition,---reducing it to very narrow
PHYSICAL AND CHEMICAL CHARACTERISTICS OF regards the water of the pneumatic trough, it should be-what
CHLORINE. ever certain books may say-cold. I state this pointedly, in 1) It& Smell.—No specific experiment need be performed in consequence of directions very frequently given, that chlorine illustration of this quality. Notwithstanding all the precau. should be collected over warm water, in order that no portion tions indicated—all the care taken-most probably some will of the gas may be absorbed. True, warm water prevents have escaped, and rendered itself manifest to the olfactory sense. absorption of the gas, but its employment gives rise to a far At any rate, beware how you proceed so smell it deliberately, more serious evil. It causes the gas to expand, to enter the tur when breathed even considerably diluted, it gives rise to receiving vessels in a rarefied condition, and finally the bottles most painful sensations. being stoppered and allowed to grow cold, and the gas con- (2) Its Colour.—The peculiar tint of chlorine is almost dis. tracting, the stopper frequently becomes obstinately fixed by tinctive of this gas or some of its gaseous combinations. It is the agency of external atmospheric pressure. This very reprlered very evident by placing as a foil, behind the bottle serious evil more than compensates for the non-absorption of containing it a sheet of white paper, the gas by hot water : nor indeed is the absorption of chlorine (3) Its Solubility in Water. This property of chlorine has by cold water sufficiently great to prove inconvenient, except already been noticed whilst discussing the best method of under the condition of ihe water being agitated, a condition collecting it; let us now direct our attention to the special altogether unnecessary, save and except the agitation referrible demonstration of that property. For this purpose, take a halfto transmission of the gas bubbles themselves.
pint bottle full of chlorine, and whilst yet inverted on the shelf
maintaining its orifice below the water-level, agitate by a sort of rotatory motion.
Gradually the water will be seen to rise in the bottle, and an aqueous solution of chlorine will result, similar to the gas itself in colour, smell, and many chemical properties. This solubility of chlorine gas in water is a very important function, of great practical utility in several manufacturing operations, more especially those of bleaching. A gns, more particularly an irritating gas like chlorine, is a very intractable agent 1 deal with, being devoid of that amount of condensed or local
energy so necessary in manufacturing operations. The
LESSONS IN ITALIAN GRAMMAR.--No. XXIII. which the manufacturer can easily apply; but there are other
By CHARLES TAUSENAU, M.D., absorptive agents, especially lime, even preferable to water in or the University of Paria, and Professor of the German and Italian this respect. They will come under our notice hereafter.
Languages at the Kensington Proprietary Grammar School: Chlorine as a Bleaching Agent.-Chemists of a bygone era,
ADJECTIVES, misled concerning the nature and analogies of chlorine, con. ITALIAN adjectives either terminate in o or in e; e. g. pô-re.ro, sidered it as an acid, which they denominated.“ Orymuriatic poor, för-te, strong. Acid," that is to say, a compound of muriatic acid plus oxygen. The adjectives terminating in o are of the masculine gender, It remained for Sir Humphry Davy to demonstrate that it was and become feminine by changing o into a. The masculine neither an acid nor did it contain oxygen, but that it was a adjectives of this class, in the plural, change o into i, and the simple chemical element. He termed it chlorine. The exact feminine, a into e; e. g. line of demonstration pursued by that great chemist we are 11 pô-ve-ro
w-ini-ni not quite in a condition to follow; but we can at least show that it is devoid of two of the most general properties of an acid, La pô-re-ra
Le pó-ve-te don-ne being neither sour to the taste nor having the property of red
poor dening litmus paper. That it is not acid to the taste may be
The article is determined by the initial letter of the word recognised by bringing in contact with the tongue a little of its which immediately follows it; e. g. il sub-li-me e-sêm- pio, watery solution.
That it does not (permanently) reddenr c-sem-pio sub-li-me, the sublime example; i sub-li-me e-semlitmus paper, may be demonstrated by dipping, a slip of wj, gli e-sém-pj sub-li-mi, the sublime examples; I d-bi-to moistened litmus paper into a bottle containing chlorine, or a Strėl-to, lo strel-to d-bi-to, the tight dress ; l' im-pré-sa pe.ri.co. bottle of its aqueous solution. At first there is a redness pro: lo-sa, la pe-ri-co ló-sa im-pré-sa, the bazardous undertaking; duced, not due to chlorine, however, but to the presence of
The adjectives terminating in e are used for the masculine hydrochloric acid developed by the reaction of chlorine on
as well as for the feminine gender. They change e into i in aqueous moisture ; soon, however, the redness disappears, and the plural ; e. g. the paper is bleached.
il cap-pêl-lo tér-de
I cap-pel-li vér-di
hats 88 parsley, be employed, or a strip of indigo, dyed cloth, or
La fo-glia vér-de Le fö-glie vér-di cloth dyed Turkey-red, or generally any coloured vegetable or
leaves anim al body, bleaching will equally result. Hence we may
Nouns terminating in the masculine in tó-re, and in the conclude that bleaching is a general function of chlorine.
feminine in tri-ce, frequently stand for adjectives following a (4) Solvent Action.-Into a bottle containing chlorine intro
substantive; e. g. uó-mo vin-ci-tó-re, victor (i. e. duce a slip of gold leaf attached 10 a glass rod. Into an
conqueror); dón-na vin-ci-tri-ce, victress (i. e. aqueous solution of chlorine introduce another piece of gold
conqueror) leaf. In either case the chlorine will rapidly act on the metal;
Italian adjectives must agree with the nouns to which they in the latter case completely dissolving it. This is a very impor- belong or refer, in gender and number, when they stand tant test
, not merely indicating the presence of chlorine gene- immediately before or after these nouns, and even when they rally, but that the chlorine is free or uncombined.
are separated from them by verbs or other words; e. g. un (6) Chlorine as a Supporter of Combustion.-Viewed under this momo dót-to e ra-gio-ne-vo-le
, a learned and sensible man; uó. aspect, chlorine is a very extraordinary substance. Its rela mi ni düt-ti e rc-gio-ne-vo.li, learned and sensible men; ú-na tions to combustion are far too numerous and of too great dón-na sa-via e pru-den-te, a wise and prudent woman; quél-le importance for summary discussion in this lesson.
We will don-ne sú-no sá-vie e pru-din-ti, those women are wise and treat fully concerning this subject in our next : meanwhile prudent; gió-va-ni pa-sto-rél-le, quin-to siê-te fe-li-ci! young prepare the following experiments.
shepherdesses, how happy you are! Procure a piece of wood charcoal, of such dimensions that
Méz-zo, when it means la me-tà, the half or moiety, in the it can easily be immersed in a bottle full of chlorine gas. singular, either agrees with the nouns or remains unaltered. It
must remain unaltered in the plural; e. g. un ó-ra e més-ea. Fig. 35.
or un ó-ra e méz-zo, one hour and a half; ú-na lib-bra e mês-za or u-na líb-bra e mêz-zo, one pound and a half; dú-e lib-bre e méz-zo, two pounds and a half.
Méz-z0, when it is used as an adverb before an adjective or participle, also remains unaltered; e. g. é-ra méz-zo môr-ta perlo spa-vén-to, she was half-dead with fright.
Of adjectives connected with and following each other, only the last agrees with the noun in gender and number; e. g. 08-ser-va-zió-ni stô-ri-co — cri-ti-che, historical and critical remarks; stú-dj po.li.ti-co-le-gd-li, political and legal studies.
An adjective which refers to two nouns of different genders, takes the plural number and the masculine gender; e. g. Ľ uo, mo e la dön-na só-no 80g-gêt-ti ál-le stes-se pas-sih-ni, man and woman are liable to the same passions ; gli ál-be-ri e le ví-ti fú-ron di-strút-ti dal-la gra-gnuô-la, the trees and the vines were destroyed by the hail.
An adjective which refers to more than two nouns of different genders, generally takes the gender of the majority of the nouns to which it refers; e. g. il pa-dre, la zi-a e le cu-gi-ne 86-no par-ti-te, the father, the aunt, and the (female) cousins -
-in de maade to enclose the charcoal tightly in a sorppor cage; gone out to take a walk. and mount the wire on a perforated zinc disc and cork, in the holy; and the masculine pronoun quél-lo, that; sometimes drop
The arijectives bèl-lo, beautiful; grán-de, great, large; sán-to, manner already followed during our experiments on oxygen.
the last syllable.
1. The above-mentioned words can only drop their last Les louanges refusées savent bien revenir avec plus de force, et il syllable when they precede a noun. est peut-être au«si modeste de leur laisser leur cours naturel en ne les prenant que pour ce qu'elles valent.-- Fontenelle.
2. The initial letter of this noun must be a consonant which is not the s impure.
de round about it, as represented, sorte dine copper wire, a pas-seg-gia-re, the sisters, the father, and the brothers have
3. They take the apostrophe before nouns commencing with them; e. g. un věc-rhio ra-gio-né vo-le, a sensible old man; ú-na a vowel.
dón-na gra zió-sa, a graceful woman; un li-bro po.co ú-ti-le, a 4. They must never be abbreviated before nouns beginning not very useful book; un o dir mol-to grd-to, a very agretable with the s impure.
od Jur; un uo-mo trop-po pe-ri co-ló-so, a loo dangerous man; 5. Bel-lo and quél-lo only drop the last syllable in the singular u-na ma-ri-na bên im-por-tan-te, a very considerable navy; un and before nouns of the masculine gender.
bô-sco co-si fól-to, so dense a wood, 6. Grán-de also drops the last syllable in the singular and 4. When participles are used in the place of adjectives ; e.g. before nouns of the masculine gender ; but, in addition to this, ú-no sguar-do com-mo-vên-te, a moving look ; un uomo e-ru-di-to, it may lose its last syllable before a noun of the feminine let-te-rd-lo, a learned man. gender, and also in ihe plural before nouns of both genders. 5. When adjectives denote natural qualities perceivable by
7. Sán-to only drops the last syllable before a proper name the olfactory organs, by the sense of tasting, or by any other of of the masculine gender and singular number, but not before the senses, or when they express bodily defects and infirmities an appellative or common name. It must also immediately or official employments and rank; e. g. pin-no fi-no, fine cloth; precede the proper name; e.g.
êr-ba a-mai-ra, bitler herb; lé-gno séc-co, dry wood; pan fré-sco,
new bread ; l' a-mór ciê-co, blind love; a piè côp-po, with a Bel giar-di-no
lame foot; il man-to im-pe-rid-le, the imperial mantle; il con. Beautiful garden
8i-gliê-re aú-li-co, the aulic counsellor; il giar-di-no im-peGran cap-pél-lo Gran cap-pêl-ha
riu-le, the imperial garden.
Where common usage has assigned to an adjective a place
before or after a noun, no positive rules can be stated, and only
a practical acquaintance with such usages, and the attentive Saint Peter
reading of good writers, will enable the learner to see his way
in such cases.
Where, on the contrary, usage gives no pre-
ference to the place of an adjective before or after a noud, și-gnó-re Qué-i si+gnó-ri
euphony, the great guide in the arrangement of Italian words, That gentleman
will best decide the matter. Some adjectives have a different Bell 6c-chio Bi-gli ôc-chi
meaning, according to their position before or after a noun. Beautiful
To illustrate this, a few of the most important phrases of this eye Grand al-be-ro Gran di al-be-ri
kind will be, I think, sufficient :-
Un ga-lunt' uô-mo, an honest man.
Un uo-mo ga-lán-te, a genteel, polite man.
E'-gli a-vé-va pró-prio ve-sti-to, he had his own dress.
Un-ve-sti-to pro-priv, a neat, clean dress,
Un gin-til uó-mo, a gentleman by birth, a nobleman.
Un wó-mo gen-ti-le, a well-bred, genteel, courteous man,
Il po-ver uó-mo! quan-to dê-ve sof fri-re, poor, unfortunate
Gran di stre-pi-ti man ! how much must he suffer.
Luô-mo pô-ve-ro, the poor man (opposed to rich),
Gran có-sa ve-ra-men-te, a wonderful thing indeed.
Có-su gran-de, a great thing.
Un dól-ce sún-no, a soft or calm sleep.
Un tem-po dol-ce, a mild season (or mild weather.)
U’-na cer-ta no-ti-zu, certain (i.e, a kind of) news.
U'-na no-ti-zia cér-ta, certain (i. e, indubitable, positive) U'-no drops the final vowel before any word commencing news. with a consonant which is not the s impure. Buô-no only drops its final vowel when immediately preceding a noun of cular prepositions after them; e. g. in, per, etc.
Adjectives frequently require a particular case or partithis description ; e. g. un giar-di-no, a garden; un pô.co, a tion must be bestowed by the learner upon this peculiarity;
Great attenlittle; buôn fi-glio, good son; un buô-no ed o-ne-sto vêc-chio, a and in reading Italian writers, he ought never to lose sight good and honest old man.
Adjectives very frequently are used in the place of nouns, and of the peculiar anıl, therefore, invariable or frequently in such cases have the article before them; e. g. il ver.de recurring cases or prepositions connected with some adjecmui-sce da u-na com-po-si-zió-ne del gial-lo e del tur-chi-no, the tives; e. g. am-ma-li-to, in-fér-mo di cør-po e di ú-ni-ma, green colour springs from a mixture of (the) yellow and (the) sick in body and in mind ; a-vu-ro, cu-pi-cio di da-nu-ri e ricblue; un pô-co di be-ne, un pô-co di md-le, a little of what is chéz-ze, greedy of money and riches; con-ten-to del-la si-eh good, a little of what is bad.
sör-te, satisfied with his lot; fran-co di pô-sta, post-free, postIn most cases, emphasis or euphony will be the best guide paid ; é-gli mi è in-fe-rw-re di run-go, he is my inferior in rank; for deciding whether an adjective is to be placed before or after pó-ve-ro di spi-ri.to, poor in spirit; ric-co di be-ni di for-tú.na, a noun; e. g. con ver-gó-gna e-têr-na or con e-têr-na ver-go-gna, rich in gitts of forrune; as-8d-i prd-ti-co del-le cî-se” an-ti-che, with eternal dishonour; un ca-vul-lo bel-lis-si-mo or un bei-lis" | very expert or skilful in matters of antiquity; nô.bi-le di nasi-mo ca-val-lo, a very beautiful horse; un con-te-gni pre-giá-sci-ta e co-stu-mi, noble by birth and in his manners; in-nobiele or un pre-gia-bi-le con-te-gno, an estimable appearance.
cên-te dell' o-mi-ci-dio, innocent of the murder or manslaughur; In the following cases, however, the learner will do best, at col-pé-vo-le del de-lit-to, cóm-p!i-ce del für-to, con-sa-pe-ro-le del least in prose, strictly to adhere to the practice of placing the fut-to, rè-o di mór-te, guilty of the crime, accessory to the thefi
, adjective after the noun :
privy to or acquainted with the deed, guilty of deathbuo. 110
ullo scó-po, good for the purpose; buo-no a niin-te, good for 1. When adjectives are derived from proper names of nations, nothing ; de-sti-ni-tv a vén-de-re, destined for sale; di-spo- sto, countries, and towns ; e. g. la let-te-ra-tu-ra in-glé-se, English pre-pa-ra-to, pron-to a ser-vir-vi, ready to serve you; tut.to in, literature ; l' ac-ca-de-mia fio-ren-ti-na, the Academy of Florence; tên-to úl-la mú-si-ca, wholly occupied with music; o-dió-so al il pó-po-lo spa-gnuô-lo, the Spanish people.
po-po-lo, odious to the people ; sog-get-to a nes-su-no, dependent 2. When adjectives express the form or colour of a thing ; on nobody; ú-na cit-tà vi-ci-na al ma-re, a town near the sea -e. g. u-na pidiz-za ro-tón-da, a round market-place ; ú-na fi-gu-ra a-lie-no dul-lo stú-dio, averse to study; de-ca-du-ti dai pri-viqaa-drá-la, a quadrangular figure ; in-chio-stro ne-ro, black ink; L-gi di cit-ta-di-no, deprived of civil rights; ê-su-le dál-la paber-rét ta rós-84, red cap; d-bi-to tur-chi-no, blue dress, tris, exiled from one's native country; casin-te da qua-lun
3. When adjectives have more syllables than their nouns, que su-per-sti-zió-ne, im-mu-ne da 6-ani gra-vés-sa, free from or the words pó-co, little ; mól-lo, much ; as-sd-i, enough, much, every superstition, from every burden; stán-co dal viag; greatly, very ; tróp-po, too much, too, excessively , bene, well
, gio, tired by the journey-vir-tuo-so nel cán-to, accomplished ustly, rightly, right ; co-si, so, thus; and similar adverbs before in singing; va-lên-te, ec-cel-len-te in poe-si-a, skilful, excellent.