bout 120 miles from
93 Marocco; it is 35 miles from the city of Marocco to the foot of
Atlas; and it is two days' journey from the foot of Atlas to the
snow, which constantly covers the summit of these immense
mountains. They are thus seen at a distance of 245 miles:

20 miles from land at sea.
120 do. Mogodor to Marocco.
35 do. Marocco to the foot of
the mountains.
70 do. the foot of Atlas to the snow.
---
Seen at 245 miles distance.
---

[Footnote 109: Ophthalmic disorders prevail among the Jews of
Marocco, but are seldom seen among the Moors. The Jews live in
great filth at Marocco; the dung-hills and ruins are in some
places as high as the houses. The Muhamedan doctrine does not
allow the Moors to neglect personal cleanliness, which, among
these people, is a cardinal virtue; and this, I presume, is the
cause of their being, in a great measure, exempt from
ophthalmia, whereas the Jews, on the contrary, are generally
affected with it.]

In this calculation, the direct distance in the ascent of the
mountain, is less than the travelling distance; but without taking
notice of the distance from the border of the snow to the summit of
this lofty mountain, which is said to be another day's journey, the
one may balance the other: we may therefore calculate 70 miles as
the direct longitudinal distance, although I am persuaded it is
much more from the foot to the summit of that part of the Atlas
which is visible at sea.

H.T. Colebrooke, Esq., in a paper inserted in the Asiatic
Transactions, vol. xii. asserts, that it requires an elevation of
28,000 feet, for an object to be visible at the distance of 200
94 geographical miles; now 245 English miles are equal to 211-1/2
geographical miles; consequently, if Mr. Colebrooke be correct, the
summit of Atlas, east of Marocco and Dimenet, which is seen at a
distance of 211-1/2 geographical miles, must be 29,610 feet high,
or above five miles and a half.

Again, the chain of Atlas in Lower Suse, which lies east of Elala,
and which is constantly covered with snow, is situated three days'
journey, horse travelling, east-south-east from Elala, in Lower