J. Orton on the Andes and Amazons. 205 
the grand Plaza. It is a singular fact that La Condamine 
(1745), Humboldt (1802), Boussingault (1831), and Visse 
(1863) give a decreasing altitude. One is tempted to believe 
that the Andes are sinking. Boussingault contends that this 
is true of some individual mountains,* The mean of all the 
estimates given in the table, excepting that of Caldas which 
is manifestly incorrect, is 9,521. Villavicencio gives 9,485. 
I quote him simply to call attention to the fact that the esti- 
mates in his Geograjia de la Republica del Ecuador are not 
reliable, Ina balloon ascent made in J anuary, 1864, from 
Woolwich, Eng., by Glaisher for the British Association, the 
reading of the barometer at 3% 16 p.m., (corrected and re- 
duced to 32°,) was 20-951 at the estimated height of 9,500 ft. 
he minimum noticed in Quito was 21:460. The French sa- 
vans give the length of the seconds pendulum at Quito 
3247753 ft., it being 3250588 ft. at sea-level on the equator. 
This is a deduction, not the result of experiment, and gives 
only 9,166 ft. for the height of Quito. _ The pendulum experi- — 
ment at Quito would be very interesting, but great distur 
ances would doubtless arise from the proximity of so many 
volcanic mountains, 
_ The observations on Pichincha were taken 80 ft. below the 
highest pinnacle. That in the crater was made at the foot of 
the cone of eruption. That on Antisana was taken just above 
average snow-limit; and that on Cotopaxi at the base of 
the cone. Cotopaxi’s cone is therefore 6,000 ft. high. At 
Ttuleache begins the series of observations from Quito east- 
b 
the Atlantic ; while I have kept the Pacific as a base. The 
barometer and boiling point at the Atlantic level are compu- 
; the distance of Para being taken at 95 miles and the 
fall = the river two inches to the mile. This makes the Pacific 
Mountains on the equator exert an attractive power on the 
Ocean at their feet? At Panama, the Pacific and Atlantic 
“net cet Common level, for there the Andes drop down to an 
significant altitude, I must add, however, that the obser- 
* See Bull. de : ce, tom. vi, p. 56, Prof. Schén from obser- 
=, at Wostibeey idea. abd the oy rt ei has increased during 
fifty years. Forbes, 1832. - 
eS £, 
BON ee ae a ce 
