ALKALIMETRY ALPS. 



203 



ALKALIMETRY means the process for testing 

 alkalies. The principle of all plans of alkalimetry 

 is the same, namely, trying how much' acid is requir- 

 ed to saturate a given weight of the alkali. The 

 acid generally employed for this purpose is the sul- 

 phuric, but nitric acid answers equally well, and is 

 indeed in the whole preferable, from this acid form- 

 ing no insoluble salts, and therefore admitting of 

 other tests being applied to the neutralised solution. 

 The acid is brought to a proper specific gravity, and 

 is then of such a strength that 100 measures of it in 

 a graduated instrument, called the alkalimeter, ex- 

 actly neutralise 170 grs. of anhydrous carbonate of 

 soda. This quantity is chosen because it contains 

 exactly 100 grs. of real soda. It is obvious that on 

 treating 100 grs. of any alkaline salt of soda with 

 this standard acid, the per centage of real soda must 

 be immediately obtained ; for, were the 100 grs. all 

 pure soda, they would require 100 measures of the 

 acid; not being pure soda, they require for neutral- 

 isation that part of a 100 which they in reality con- 

 tain. Litmus paper is used to ascertain the precise 

 point of neutralisation ; a little drop of the liquid 

 is taken out on the end of a glass-rod and applied to 

 the paper. If the paper be rendered blue there- 

 by, more acid is required ; if it be reddened 

 thereby, there has been too much acid added, and the 

 limits of neutralisation over-stepped. To remedy 

 this blunder, an alkaline solution of known strength 

 may be kept to neutralise the excess of acid. This 

 is the plan adopted by the bleachers and painters 

 for ascertaining the strength of their soda-ash, of 

 rough carbonate of soda, as well as the value of 

 kelp, barilla, &c. Some such process as the above 

 is absolutely necessary, where the price of an article 

 of commerce differs according to the proportions of 

 the ingredients in each sample. To test the potashes 

 and pearl ashes of commerce, the same standard acid 

 is employed, but 152 grs. are employed instead of 

 100 of carbonate of soda. The number of measures 

 of acid required to produce neutralisation gives the 

 per centage of potash in the specimen. The im- 

 purities of potashes are sulphate of potash and 

 common salt, and of soda-ash, the sulphate of soda 

 and common salt. The positive presence of these 

 bodies is indicated by nitrate of barytes for the 

 sulphates, and nitrate of silver for the common salts 

 These two tests must be applied to the solution of 

 the alkalies in pure nitric acid and distilled water. 

 Crystals of carbonate of soda contain 21-8 p. c. 

 pure soda, and good soda-ash from 42 to 48 p. c. 



ALNWICK, in the county of Northumberland, 

 (a). Population in 1831, 6788. 



ALPS (a). To the readers of history, and of 

 poetry, the Alps are a familiar name. From the 

 days of the Romans, down to the present century, 

 their inaccessible heights, eternal snows, and dif- 

 ficult and precipitous defiles, have given them a 

 celebrity, hardly possessed by any other features of 

 continental Europe. Placed as a natural barrier 

 between nations frequently dissimilar, or hostile to 

 each other, they have stood, abrupt, and impene- 

 trable, as they were left by the deluge; and the 

 little that man could do, in opening their avenues, or 

 smoothing their passes, remained almost unat- 

 tempted until the nineteenth century. But within 

 the times of the present generation, and especially 

 within the last five or six years, the aspect of these 

 mountains has become less solitary and forbidding. 

 Over nearly all the important defiles, smooth arid 

 spacious roads have been constructed, rocks have 

 been penetrated, abysses have been spanned, ter- 



races upon terraces have scaled the loftiest passes, 

 and the traveller who now rolls over them at his 

 ease, secure of comfortable hotels, and regular re- 

 lays of post horses, troubles himself little about the 

 difficulties against which Hannibal urged his ele- 

 phants, and Bonaparte dragged his artillery. 



The mountainous country, usually denominated 

 the Alpine region, covers a great portion of the 

 continental territory of the king of Sardinia, the 

 republic of Switzerland, and the Tyrolese dominions 

 of Austria, together with portions of the im- 

 mediately adjacent states. But the great or prin- 

 cipal chain may be considered as forming a half 

 oval, or crescent, having the valley of the Po in 

 its centre, and the Gulf of Venice at its base. This 

 chain commences in northern Italy, where it is con- 

 tinuous with the Appennines, and, skirting closely 

 upon the Mediterranean along the Gulf of Genoa, 

 turns to the north through Piedmont and Savoy, in 

 which countries it throws up its loftiest eminences. 

 It then passes easterly through Switzerland and the 

 districts of Tyrol and Carniola, until it is merged 

 in the less elevated ranges of eastern Europe. The 

 geographical effect of this distribution is to separate 

 the waters of the Po, from those of the Rhone, the 

 Rhine and the Danube. 



The most interesting features in the Alpine 

 chain, are the depressions, or passable gaps, and 

 the extreme elevations. The depressions, or 

 notches in the summit of the ridge, furnish avenues, 

 over which mankind, following the tracks of the 

 chamois, have constructed mule paths, and after- 

 wards roads practicable for carriages. These are 

 seldom less than five thousand feet above the level 

 of the ocean, and are mostly named from the moun- 

 tains near which they pass, as the Simplon, the St 

 Gothard, and the Splugen. The great elevations 

 are for the most part abrupt and towering peaks, 

 many of which, from their sharpness and steep ac- 

 clivities, have received the appellation of horns and 

 needles. Among the most elevated peaks are 

 Mont Blanc, Mont Cervin and Monte Rosa, situ- 

 ated in the chain which divides Piedmont from 

 Savoy and Valais ; the Finstraahorn, the Schreck- 

 horn (horn of terror), and the Jungfiau, in Swit- 

 zerland; and the Ortler-spitz in the Tyrol. The 

 distinction of being the highest mountain in Europe 

 has been lately contested between Mont Blanc and 

 Monte Rosa. Since the observations of De Saus- 

 sure, no doubt had been entertained that Mont 

 Blanc was entitled to this precedence. But in 

 1819 one of the inferior summits of Monte Rosa 

 was ascended by Messrs Zumstein and Vincent, 

 who took trigonometrical observations of the 

 higher peaks, and arrived at the conclusion that 

 these inaccessible summits were more elevated 

 than the top of Mont Blanc, by some hundreds of 

 feet. Their account, published in the Memoirs of 

 the Academy of Turin, immediately drew towards 

 Monte Rosa the attention of the scientific, and 

 travelling public, new admeasurements were under- 

 taken, and from an elaborate topographical account 

 and survey of this mountain by Baron Welden, 

 published at Vienna in 1824, it. would appear that 

 the altitude of the two eminences is nearly equal, 

 Mont Blanc, however, having the precedence by 

 about eighty-eight toises.* 



* The probable height of Mont Blanc is about 14,764 I aria 

 fppt. That of Monte Rosa 14,222. See an account of the latter 

 mountain in Brewster's Edinburgh Journal of Science, vols. i. 

 and ii. \a the upper stratum of these mountains consists of 

 snow, it is vory probable that their height varies in different 

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