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his re-appearance above it at Nova Zembla, in latitude 76°, that the horizontal refraction must at that time exceed 4o. Observations are now making in Upper Canada on this interesting subject: and we understand that instances have occurred where it appeared that the terrestrial refraction was equal to full one-half of the intercepted arc.
We cannot think, with Mr. Colebrooke, that the altitude of Mont Blanc taken by De Luc, from Pregny, is a proper 'test of comparison' for his measurements of Dhawala-giri.—An angle of 3° 14' taken at the distance of 42 or 43 miles is not subject to the same uncertainty with regard to refraction as an angle of 1° 28' at the distance of 136 miles: besides, a difference exists in the various trigonometrical measurements of Mont Blanc of nearly 500 feet: and if the error of a quarter of a mile in distance produces, as he admits, an uncertainty in the computed elevation, of 180 feet; it requires in our opinion a much less error even than that to which all the observations he notices are obvoxious, to produce ten times that uncertainty in the elevation of the object. It is also admitted, indeed it is matter of calculation, that the error of a minute in an observation of altitude affects the calculation of the height about 200 feet for the most distant station; a small error therefore in the allowance for terrestrial refraction (and in this there always must be an error) may affect the calculation of height by as many thousand feet. If those errors from altitude and distance should happen to be on the same side, the result may far from truth in the case of the Himalaya, as it was in that of the peak of Teneriffe, whose height has been reduced from fifteen thousand feet, once assigned to it, to twelve thousand: in short, if the calculations of Mr. Colebrooke should err in the same proportion as those of Dr. Heberden, by cutting off six or seven thousand feet from the height of Dhawala-giri, we shall bring it down to the elevation of Chimboraço. "But,' says Mr. Colebrooke, “it would be an extreme supposition, that the errors have, in every instance, been the highest possible, and on the side of excess.' If the instances were numerous, it would be so, as far as distance is concerned; but, strictly speaking, there are but three: with regard to small angles of altitude, they are always more likely to be on the side of excess than otherwise.
Let us, however, endeavour to try the enormous height assigned to Dhawala-giri by another test: the only remaining one in the absence of barometrical observation,--that of meteorological phe
It has been pretty well ascertained, partly from facts and partly from theory, at what elevation above the level of the sea, in dif. ferent parallels of latitude, snow ceases to melt; or more correctly
speaking, where it always freezes at night; because the sun will melt snow at a much greater elevation than that of perpetual frost. No general scale, however, can be given, as the situation of the land with regard to its summer temperature, its general elevation, and its distance from the sea, will very materially affect the height of what is usually denominated the lower term of perpetual congelation.' Thus the peak of Teneriffe which, though 12,000 feet high, is free from snow at least four months in the year, would, if placed on the continent in the same parallel, have a perpetual cap of snow covering several hundred feet from the summit, while the snow on the sides of Mont Blanc, which never melts at 8,300 feet above the level of the sea, would, if that mountain were placed in the middle of the Atlantic, on the same parallel, disappear in the sunimer months as high up at least as ten and probably eleven thousand feet. For our purpose, however, Mr. Kirwan's table of the mean height of the lower term of perpetual congelation, will be sufficient. According to this, the point above the sea, at which snow. does not melt in the parallel of 30°, is 11,592 feet: now as that part of the Himalaya where Mr. Webb's observations were taken, is rather more; as the distance from the sea is very considerable, and the range surrounded by high mountains on one side, and supported by an elevated table laud on the other, which keep the atmosphere in a constant state of refrigeration, we may safely venture to assume 11,000 feet, as an elevation beyond that at which perpetual snow rests on the sides of the Himalaya.
Now it is quite clear from Mr. Moorcroft's narrative, that in crossing the Himalaya, no snow whatever occurred either on the 1st July or the 29th August, and consequently that the summit of the Niti Ghati pass is less than 11,000 feet, as the rise from a good grassy plain' on the left bank of the rivulet, which falls into the Dauli, is stated to be no more than 1750 paces, (the pundit's strides, we presume,) but very steep; supposing that to every two feet of slope we allow one of perpendicular ascent, and estimate the grassy plain at 6000 feet, we shall have about 9500 feet for the elevation of the summit of the Niti pass. This is described as half a mile wide, so that there is room enough for the traveller to look round him. If then the cheeks of this pass had risen above it to the height of ten, twelve or fourteen thousand feet, it can hardly be conceived that the observation of objects of such tremendous grandeur and sublimity would not have furnished matter for some remark in the journal-not a syllable, however, is set down, not even a note of admiration !- all we find, .is the meagre fact, that on the morning after they had re-crossed the range, - snow was falling on the adjacent mountains. An observation, however, subsequently occurs, which is to the purpose. In crossing the table land to the
northward, Mr. Moorcroft says, on the south, the plain is bounded by the last Himalaya ridge, just tipped with snow in stripes like foot puths, extending along the windings of the ridges ; on the north by the Caillas mountains, the summits of which are marked more distinctly with snow:' (p. 420) yet he observes, in another place, that the very highest peak of the Caillas, (the Cailása of the charts,) called by the Hindoos Mahadev'ka-ling, was tipped with
When close to these mountains and the Himalaya, where they approach each other near the Mansarowar lake, he speaks of vast bodies of snow on the summits of the neighbouring mountains, and notices, in particular, “the snow-capped neighbour' of the Caillas ridge, the Hemachal range.' These are not indications of an altitude of twenty-six or twenty-seven thousand feet. We lay no undue stress on the loose statements of Mr. Moorcroft; but, coupling them with the insignificant height at which Captain Turner states the Chamalári to have appeared above the table land of Thibet, (itself, at the utmost, 8000 feet high,) but which is now swelled to some thousands beyond twenty above the level of the sea, we cannot resist the conclusion that the elevation of the Himalaya range has been greatly exaggerated.
There is still another circumstance which may be brought in aid of the argument against the vast elevation assigned to the Himalaya mountains. It was long supposed that the density of the atmosphere was so much diminished at the height of about four miles, that no clouds could be sustained in it; and though Chimboraço, which is nearly four miles, is covered with snow,
and consequently must have had clouds floating above it, yet that mountain formed an anomaly which could only be explained by the great mass of high land in the vicinity producing such an intensity of cold, as to give to the surrounding atmosphere a degree of density, sufficient to enable it to support vapour in the state of clouds, which in its ordinary temperature, at the same height, could not be sustained. But the assumed height of the Himalaya is a mile above that of Chimboraço. We believe, however, that experiments are still wanting to ascertain the height to which vapour will rise in the atmosphere, or that, at which it can be sustained in the state of water; and that at present very little is known on this subject. Mr. Dalton, in his Meteorological Essays, says that “ by some careful observations he has found the small white streaks of condensed vapour which appear on the surface of the sky, to be from three to five miles above the earth's surface. These are unquestionably the lightest shapes in which condensed moisture can appear : and it would follow that if the height of Dhawala-giri peak exceeds that of five miles, there is either no snow on its summit, or that the atmosphere, which surrounds the tops of lofty mountains, must ob
serve a different law from that which embraces the general surface of the earth. Perhaps the phenomenon will admit of being explained by the supposition that the atmosphere round the summits of high mountains deposits its moisture on them, without forming clouds, in the shape of rime; such as we see on the surface of the ground, or the windows of a room, on a clear frosty morning.
That the measurenients given as 'near approaches to a correct determination of the height of the Indian Alps,' are generally and greatly exaggerated, we may safely infer from the result of observations made by Lieutenant Webb, subsequently to the calculations of Mr. Colebrooke, and communicated to us since we entered on this Article. They embrace the altitudes of twentyseven different peaks of the snowy chain, determined, as he assures us, trigonometrically, and proved by inferring the latitude of Pilibhit, from the position of the peaks as ascertained by survey; which, he says, ' coincided with Mr. Burrow's observations to five seconds of a great circle, or 84 fathoms'—though the distance between the Great Mosque in that town, and the nearest point in the snowy range is 98,000 fathoms, or 112 miles'—this will probably be thought to prove too much.-We regret that the want of corresponding names or numbers will not adınit of comparing Lieutenant Webb with himself, or rather with the results of Mr. Cole brooke, obtained from his former observations: we shall insert them, however, as records to be hereafter referred to in our Journal, and for general comparison with the results of Mr. Colebrooke's calculations, which are as under :
Dhawala-giri (on the lowest computation') - 26,862 ft.
24,740 A nameless mountain
22,768 Another nameless mountain
24,625 Another, near the last,
23,262 A third, in its vicinity,
23,052 The results of Mr. Webb's observations, taken during his survey of Kamaon, are as follows. No. of Peak. Altitude. No. of Peak. Altitude. No. of Peak. Altitude, No. 1 22,345
No. 10 15,739 No.19 22,635 9. 22,058 11 20,681
20 20,407 3 22,840 12 23,263
21 19,099 21,611 13 22,313
22 19,497 5 19,106
24 92,238 7 22,578 16 17,994
25 22,277 8 23,164 17 19,153
21,045 9 21,311 18. 21,439
These altitudes, it will be noticed, are very inferior to those of Mr. Colebrooke. One observation more and we have done. The first nameless mountain of Mr. Colebrooke's list was calculated by Lieutenant Webb at 21,000 feet above the plains of Rohilkhund, or 21,500 above the level of the sea, from a mean of numerous altitudes, taken at different times of the day, with an excellent instrument, its distance being previously ascertained by observation, from the well determined extremities of a sufficient base.'* We now find it stretched out to 22,768, and all the others seem to have grown in the same proportion. On every consideration, therefore, we conceive that we are borne out in concluding, that the height of the Himalaya mountains has not yet been determined with sufficient accuracy, to assert their superiority over the Cordilleras of the Andes.
ART. VI. Les Théâtres. Par un Amateur. Paris. 1817. 8vo.
THE influence of the stage upon the morals and manners of a
people is now so generally admitted, that we shall not be guilty either of the common-place of enforcing it, or of the temerity of denying it. We are inclined to believe, however, (as we lately took occasion to observe,) that this influence, as far as it regards England, is a little over-rated—we doubt that the Beggars' Opera ever made an additional highwayman, or that Gay was entitled even to Mr. Courtney'st lively praise of being the Orpheus of highwaymen.
We readily admit however the policy of the act of the 10th Geo. II. c. 28. for licensing plays and play-houses; the very nature of the stage justifies this restriction on the general liberty, subject only to our ulterior responsibility, of speaking and writing what we please. Mischief once promulgated on the stage is irremediable—it is addressed to thousands, who on many accounts are peculiarly liable to receive strong and sudden impressions; it is enforced upon them by all the magic of theatrical illusion, by the splendour of poetry, or by the vigour of eloquence; and a libel might be promulgated, a riot created, and characters and lives lost before even a constable at the door could interfere.
If, then, in this sober country, which has been so long accustomed to enjoy its freedom with moderation, it be thought necessary(and we never have heard, since the passing of the licensing act, a contrary opinion)—to have some previous restriction, we cannot be
* Mr. Colebrooke's Essays on the Source of the Ganges, vol. xi. Boswell's Life of Johnson, vol. ii. p. 374.