THE VOYAGE OF H.M.S. CHALLENGER. 
'24 
lh* Vi kits on THE 
Level or mi 
Ocean. 
Mirr*i.CR. Tub 
Moirarjogi Wind. 
tmiu rivi-i> is not transported to great distances, for matter in suspension is arrested by 
: ' .v in- nts of the sea ; the bed of the ocean is not, in consequence, filled up so rapidly 
-on would think, but the places near the coasts are loaded with sandy materials, and it is 
■ * , 1( that the greatest modifications take place. Finally, he attributed to winds an active 
; : ; iii the ch anges taking place at the surface of the globe. To the combination of 
- forces he attributes what has since been called the sculpturing of the continents. 
As to the form of the oceanic basins and the relief of the bed of the sea, he believed 
t ,i ; here were valleys and mountains as on emerged land. All the seas which 
re united together, and all the parts of the great ocean which surround the knowm 
... ..rid, h v. the same level, the surface of their waters is spherical, and the centre of 
- oh re coincides with the centre of the earth'; this notion cannot but be regarded 
us .great advance on that of Eratosthenes, who asserted that not only different seas but 
rt ii re A" ns of the same sea had different levels, wilich latter view is now believed to 
mj true to a certain extent, although Eratosthenes did not prove it. Strabo believed 
Ait > ii quilibrium was only established after the Black Sea and Mediterranean had 
burst their barriers, in the manner described by Eratosthenes and Strato. The 
Continuous current flowing from the Black Sea through the Bosphorus chiefly induced 
him to adopt this theory, but he rejected the view of those writers who argued that the 
lime nt brought to the Pontus Euxinus by rivers could have any considerable 
• ;f.-< • in filling up that sea and causing it to overflow. In speaking of waves, Strabo 
point out that whatever their force may be, it increases’ as the weaves approach 
- i>; . — this recrudescence of the wave on the coast does not depend on the force 
■ <f the wind, for the phenomenon takes place in a calm or with the wind off 
-!- likewise points out the relation between the length of the coast-line of a 
and its arc ., and the influence of this purely geometrical fact on civilisation, 
■ tii st ii ti iment of transmission is the sea. It is somewhat odd that Strabo makes 
.. in- nt: -n of currents in the Mediterranean, although these are sufficiently pronounced 
in - >m< instances. Strabo suggests that besides the world known to the Greeks and 
1: -Mian*, other continents or other worlds might yet be discovered inhabited by different 
r - of men. 1 Enough Lies been said to skow T the remarkable correctness of the 
O 
bservations and views of this celebrated Greek; many of them approach the concep- 
- - f mo-1- rn <_ r -logy, and have been confirmed by modern research. (See Plate IV.) 
Str.iUj d.e not appear to have been acquainted with Hippalus, an Egyptian 
navigator, who lived <d>out the same time, and proved the regular alternations in the 
• < t »n of the monsoons of the Indian Ocean, and profited by the discovery to open up 
i r-'Ut-- whs the high sea.s between the shores of the Red Sea and India. 2 The monsoon 
* Strabo, L 4, ii. 5. 
' .'if i F.r'fthru i, 67, ed. M iller ; Pliny, Hint. Nat., vi. 23, sec. 100; Vivien de St. Martin, Lc Nord de 
CAfrvpu dan * fantiquU/, p. 269, Paria, 1863. 
