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combined with the metal, are not points for discussion at present. One object was to get a solution of manganese, and we have got it: let us now study the properties of this solution. Our proposition is to precipitate or throw down the dissolved manganese. How can this be effected? The student succeeded in throwing down zinc by means of hydrosulphuric acid, either in the form of aqueous solution or gas. Will these agents throw down manganese ? On trying the experiment, the reader will find that the manganese cannot be precipitated by this means. The solution will either remain absolutely clear, or will only become slightly turbid; the manganese remaining dissolved. But if instead of hydrosulphurie acid gas, or solution of this gas in water, a solution of the same in aiamonia (hartshorn) be employed; or, what amounts to the same thing, if a little hartshorn be added to the manganese solution simultaneously with the hydrosulphuric acid, then all the manganese will be thrown down or precipitated. If the manganese solution be pure, the precipitate will be white, or rather flesh-coloured (we will call it white by courtesy); if the solution contain iron or some other metal—a very probable contingency—then the white or cream-colour will be proportionately disturbed. What I desire especially to impress upon the student's consideration is this. Zinc is precipitäted from its solution white by hydrosulphuric acid alone, whereas manganese is precipitated white (by courtesy) only when the hydrosulphuric acid is combined with ammonia or hydrosulphate of ammonia. Hence we at once deduce a valuable power in analysis. Supposing zinc and ammonia to exist together in one solution, they may readily be separated by applying the principles already déduced. Passing a current of hydrosulphuric acid gas through the comipound solution, without the presence of ammonia, all the zooie will be thrown down ; repeating the operation with the presence of ammonia, or still better, hydrosulphate of ammonia already prepared, the manganese will fail. Both these precipitates will be sulphurets; one of zine, the other of manganese. The reader will how observe that although we just Row dismissed the metal zine, this was only for a time. Its consideration is now reopened in connexion and by contrast with manganese: chemical philosophy, in point of fact, is a structure made up of this comparative knowledge of different bodies. In addition to the fact that zinc is precipitated by hydrosulphuric acid alone, and manganese by hydrosulphuric acid in combination with ammonia, let the reader remember that a white precipitate by either of these agents is altogether exceptional. The usual colour of precipitates by hydrosalphuric acid and hydrosulphate of ammonia is black. . Two metals are alone precipitated white: these are zinc and manganese. The student will now recognise à means by which
*inc and manganese, if existing together in one solution, admit :
of being separated; he will perhaps remark, however, that we
do not separate the metals—obtaining zinc bodily, and manganese :
Bodily—but obtain, either a metal or a sulphuret., . He will perhaps desire, like most beginners, to obtain this bodily presence of the metals. To this extent I cannot gratify him in the present lesson. , Suffice it to say, that the process of removing sulphuric acid may be aceomplished—is accomplished in the reduction of metals from their ores—but would be difficult to accomplish in our present case; it is never accomplished in the course of analysis. ... Chemists arrive at some of their most correct results by collateral reasoning and calculation ; thus, knowing that the white sulphuret of manganese is made up of parts sulphur, and—pants manganese—that the white sulphuret of zinc is made up of parts zinc, and—parts sulphur—of course it is easy to calculaté the amount of metal and of sulphur present, with
i. actually separating the sulphur and obtaining the metal dily.
It is a very common error for chemical beginners to imagine |
that a certain result will always follow the addition of a certain substance to a solution of the same body. Thus, for example, a beginner might imagine that zinc, in whatever state of solution, will always be thrown down by hydro
sulphuric acid, and that manganese, in whatever solution, will sways be thrown down by hydrosulphate of ammonia. This
is not so. The conditions necessary to ensure these, or any other chemical results, lie in a comparatively narrow space; they can only be learned by practice, and the appreciation
formed of them constitutes the main point of difference between an expert and an inexpert chemical analyst. . For the present we will have done with manganese and zinc, my especial object being to fix on the reader's memory the nature of the changes effected on solutions of these metals by hydrosulphuric acid, and hydrosulphate of ammonia. The reader must not infer that the re-agents mentioned are the only ones for zinc and manganese; there exist several of equal delicacy, but the fact especially to be remembered is this:-Hydrosulphuric acid, and hydrosiophate of ammonia, are tests for all those substances which a beginner would consider to be
“Which a beginner would consider metals,”—what is the meaning of this expression ? Why, the meaning is this: Lime, clay, and other earths, the beginner would not suspect to be metallie compounds;–they are nevertheless; they are each an oxide, or rust of a corresponding metal; and the metals which form earths are said to be terrigenous or earth-making metals. Again, the reader does not usually associate the idea of a metal with the alkalis, potash, and soda: nevertheless, these also are oxides or rusts of corresponding metals which are said to be kaligenous or alkali-making metals.
Well, then, let the student remember the following facts:—
1. Neither the earth-making northealkali-making metals are precipitated from their solution by either hydrosulphuric acid :
2. All the metals remaining, constituting by far the greater number, and termed by chemists calcigenous metals, are precipitated by hydrosulphuric acid or hydrosulphate of
5. But solutions of zinc and manganese yield a precipitate 6. And solutiotis of arsenic, eadmium, antimony, and per
The preceding are amongst the most important of fundamental chemical facts; the reader should master them. thoroughly, not resting conteht with being able to think them out, but the facts should become part and parcel of the brain itself, so that the student, if roused from his slumbers at night, and asked any questions involved by the six generalisations which have been given, should be instantaneously able to
There is yet another class, of which the stem ends in v or As examples take # flug, fity-og, the nose; 6 ôexpuc,
oranganese, cobalt, and niekel, , are precipitated by either
remains at the end of the word and before consonants, but disappears in the middle between vowels. Nouns in suchave, in the accusative singular a, and in the accusative plural ac; take in the genitive singular what is called the Attic form in wg, instead of oc; and in the dative singular as well as in the nominative plural, admit contraction; which, however, is commonly not found in the accusative plural. If a vowel precedes evc, the whole singular and plural is contracted, as in Xoevg. Nouns in awg and otic take the contraction only in the accusative plural. The words about to be declined are 6 §agiXévc, a king; 5 xoevc, a measure of liquid (about a gallon); 6, § 800c, a bull or cow, an ow (Latin bos, bovis); and Ypatic an old woman.
middle between two vowels. In the dative plural one a disappears, e.g., § 609, a jackal, roug 60-gu. Of these words, let us consider, first, those which end in nz, sc. The terminations me (m. and f.), eg (n.), belong only to adjectives, and to proper names terminating in adjective forms in vng, Amc, yewmg, kparng, pumöng, trauðmg, a 6evng, and (c\smg) k\sig: The neuter presents the pure stem. The words of this class suffer contraction in all the cases, except the morninative and vocative singular, and the dative plural, after dropping the or. The words ending in k\eng being contracted into k\sig, again undergo contraction in the dative singular. Learn both the contracted and the uncontracted forms I am about to give of 6, #, oapng, clear, rooapsc and j rpumpng, a Trireme, or galley with three banks of rowers
Mark the contraction in the dual of rpumpss into rpumps, and not into the usual form in st. >
In adjectives in mc, sc, when these terminations are preceded by a vowel, ea is commonly contracted into a, as sisperosa, and not into n, as in oapsa gaspij; for example, ak\sic, un*ēnowned, makes akxésa into ak\sā, in the masculine and feminine accusative singular, and in the neuter nominative, accusative and vocative; so in unc forms byū. . . Proper names of this termination, as well as Apng, Mars, in the accusative singular, follow the first as well as the third declension, and are therefore denominated Heteroclite (that is, of different declensions); accordingly, we have both 20kpatm and Pokparmy. But in those ending in k\ng, the accusative in mv is not Attic, and therefore mot allowable. ! Vocabul.ARY. Akparng, ec, immoderate. A\m0ng, sc, true. ATvXng, eg, unfortunate. Apaving, sc, unknown, unseen. "EAwóng, sc, marshy. "Hpak\sic, ovc, č, Hercules. Xopox)\ijg, ovg, Ö, Sophocles. AovXeta, ag, à, slavery, servi
tude. Ivöurn, j, India. Out)\ta, ), intercourse (dat.)
Italian. IPronounced. English. Veggo veg-gof I see Figgi fid-jee Fasten Oggi ôd-jee To-day Pugg; fóod-jee Flyl Pace pāh-tchai Peace Pece pāi-tchai Pitch. Pizzo pée-no Pine Poco pô-ko Little Pute pôo-tai He has a bad smell Riparo ree-pâh-ro I repair Impero im-pé-ro Empire Tapino tah-pée-no Wretched Sapone Sah-pó-nai Soap Impune im-pâo-mai TInpunished Pappa. pāhp-pah Pap for children Peppe pép-pai Joseph, Joe Pippo pip-po Philip, Phil Coppa köp-pah The occiput, goblet. Zuppa tzôop-pah Soup Tabe tāh-bai Consumption Teco tāi-ko With thee Tipo tée-po Type (a model) Topo tö-po Mouse Tubo tóo-bo Tube Altare ahl-táh-rai Altar Altero ahl-tê-ro Haughty Altire ahl-tée-rai To mount Alloro ahl-lô-ro Laurel Altura ahl-tóo-rah Height Atto ãht-to Act, action Getto jët-to Cast, throw JFitto fit-to Rent Cotto köt-to Cooked Tutto tôot-to All, quite Vano vāh-no Vain Vero vái-ro 'rue Vino vée-no Wine TVoto v6-to Wow Avuto ah-vöo-to Had Bavaro bâh-wah-ro Bavarian Severo sai-vé-ro Severe Livino dee-vée-no Divine Lavoro lah-vö-ro Labour Lovuto do-w60-to Debt, duty Davvi, dāhv-vee He gives you Evvi év-vee Is there Udivvi, oo-div-vee. He heard you Dowvi dôv-vee I give you; Jovov; föov-vee Was there
i. When the gg's are followed by a, o, or to, they are pronounced
* In this and a few other cases, I am compelled, for the sake of completeness of system, to make a slight departure from strict orthography. This word being properly written Mazzara, as well as the following words gazzera, azzino, bazzotto, azzuffa. . .
f There is very little difference between the pronunciation of the single 2 and 22. The zz, as well as 2, may have the sound of to in the word switzer, or dz in the word adze. According to modern orthography, the z is generally doubled between two single vowels in the middle of a word, but not after a consonant and not before diphthongs the first vowel of which is to as, for examples, ia, is, to where it must remain single, and has th” hard sound.
|from one word to another, and often from one syllable to the
other, bychanges of consonants.
* The er like the sound of the syllable er in the English word error.
La Tangue latine et la langue grecque 8e Bont longtemps parlées. LEMARE.
The Latin and Greek languages | were long spoken of:
Il est vrai, qu’elle et moi nous
goous'Bommes parle des yeux. MOLIeRE.
It is true, that she and I have spoken to each other with our eyes.
Néanmoins, il s'était conservé i’autorité principale. BoSSUET. vée dans l’Asia, n'est pas sans opulence. VOLTAIRE.
The pastoral life which has been preserved in Asia, is not without
(2.) Wher: * :onominal or reflective verbs, of which the second pronoun is an indirect regimen, are accompanied by another pronoun, or by a moun, used as a direct regimen, the participle agrees with this latter pronoun or noun when it is preceded by it, and remains invariable when the régime direct follows. See Rules (4.) (5.) of the preceding section :
Nevertheless, he had preserved to Shimself the principal authority.
La wie pastorale qui s'est conser
* Noël and Chapsal, page 165. Several grammarians callen at times g régimen direct. we thio with Bescherelle (Dictionnaire national, * 1114), that en does not represent the entire direct regimen, but only a part itself under
books? I has
stood. Ex. Avez-vous des livres? J'en ai. Have you * some. In the latter sentence, the words quelques uns, the direct object, is understood after the verb; Joen at quelques uns, and en is rather a reference to it, than a substitute for it. The literal translation of the sentence will show this : I have of them a setts.