366 Geographical Collections. 
houses are found up to 14,400 feet. Mr. Pentland quotes as examples the post- 
house of Poti, (lat. 16° 5’ 30”,) and that of Apo (lat. 16° 11’) in the Cordillera, be- 
tween Arequipa and Puno. Many villages are up to 14,275 feet in height, such as 
that of Tacora, at the foot of the volcano at Chipicani, on the north-western side, 
(lat. 17° 51’,) between La Paz and Tacua. The most populous towns of High 
Peru, such as Potosi, Puno, Chucuito, are above 12,800 feet in elevation, as may 
be seen in the table below. The most elevated habitations in the globe, occur, 
then, in these countries. Not only isolated houses, but villages and towns are 
met with at the height of the shepherd’s hut at Antisana, in the province of 
Quito, where Mr. de Humboldt made his magnetic experiments. 
The phenogamous plants which Mr. P. found at the greatest elevation, belong 
to the Gramine and Composite. Upon the slope of the INimani, they attain an 
elevation of 15,500 feet, and upon the Cerro of Potosi 15,700 feet ; lands are cul- 
tivated to an elevation of 14,000 feet. Rye, potatoes, maize, kidney beans, and 
even the barley of the old world, are reared in abundance upon the shores and 
islands of the lake of Titicaca, at 12,760 feet of elevation. The maize of these 
islands has much reputation. 
Mr. P. made-a great number of observations in relation to the horary variations 
of the barometer, upon plains from 9 to 14,000 feet in elevation, which form the 
base of this part of the Andes. At these great heights, and up to 20° of south 
latitude, he has found these variations in astonishing regularity, and almost 
equal to those which are observed under the equator. He also made a great 
number of astronomical observations, with good instruments, to determine the 
position of several places of this country, which did not appear to be accurately 
placed on the map. 
Note to the above.—The graphic method, in imitation of the Mexican pro- 
files, has been applied to the chain of the Caucasus by Messrs. Parrot and En- 
gelhardt, to the Alps of Switzerland and to the Carpathian mountains by Mr. 
Wahlenberg, to the mountains of Germany by Messrs. Schubler and Hoffmann, 
to those of France by Messrs. D’Oeynhausen and Dechen, to the Capitanerie of 
Minas Geraes by Mr. D’Eschwege, and to the mountain plains of Mysore, and 
the Ghats of Malabar, by the engineer officers attached to the triangulation of 
Major Lambton in India. 
The elements of this graphic method are the results of barometric or geodesic 
levelling, the precise knowledge of distances’, the astronomical determination of 
the points of intersection, or axes of rotation of the partial profiles, and lastly, 
the angle which each projecting plain makes with the meridian. 
From these data, it had been deduced that the culminating points, or the max. 
ima of the lines of crest of the principal chains of mountains in Europe, America, 
and Asia, were as the numbers 10, 14, 18, 24, that isto say, that they nearly 
followed a progression by differences whose relation was one-half; but that in 
the seven chains of the Alps, the Andes, the Himalaya, the Caucasus, the Alle- 
ghanis and Venezuela, the relation of the crest to the summit, that is to say, - 
the relation between the mean height of the crests and the culminating points, is 
very regularly as 1 to 1,8, or as 1 to 2. 
We are enabled, from the excellent work of Lieut.-Col. Tod, to give a profile of 
the plateau of Central India, * the Aravulli and Aboo mountains ; and the labours 
of Mr. Pentland, the analysis of which we have terminated in this present num- 
ber, throw a new light upon certainly the most interesting group of that great 
Cordillera which courses through the two Americas. 
We have, among the results of these labours, the determination of the follow- 
ing cols, ports, or passages in the Andes of Peru: 
Western Chain. 
Port of Chullunquani, upon the road of La Paz to Tacua, - 15,560 feet. 
* This profile will appear in our next Number. 
