A RECENT VISIT TO THE DALMATIAN COAST. 47 
an Alpine sky; I have often seen our English skies of deeper 
azure than we saw on any occasion in the Mediterranean in the 
month of May. The colour of the sea is quite independent of 
that of the sky above, and is of a deep liquid blue which transcends 
all powers of description. 
How are we to account for this marvellous colour? It doubtless 
has an origin similar to that of the azure of the sky, #e., it is not 
due to any inherent colour of the medium itself, but to the 
particular state of division of minute solid particles in suspension. 
When the dimensions of the particles are reduced to such a state 
of minuteness as to bear a sensible relation to the dimensions of 
the light waves, the light which is reflected from the medium, 
whether it be air or water, is no longer composed of the waves of 
various refrangibilities mixed in the proportions constituting 
ordinary white light, but the rays of smaller wave length, that is, 
those of the blue or more refrangible end of the spectrum, are 
reflected in greater proportion by the minute particles, and the 
emergent light consequently has a more or less blue tinge. The 
greater the amount of subsidence of the grosser particles, the 
greater is the residual proportion of the more minute, and the 
bluer is the reflected light. 
Now, owing to the great depth of the Mediterranean, and to the 
comparative absence of currents in these deep basins, the con- 
ditions are favourable for the complete subsidence of all but the 
most minute particles, hence the purity and depth of the blue of 
the Mediterranean water as compared with that of the open 
oceans, 
As we approach the Dalmatian Coast, or sail along it within the 
belt of islands, which, like the Norwegian Skjaergaard, extends as 
_ anatural breakwater for several hundreds of miles, we see, lying 
between the far distant mountains and the sea, a narrow tract of 
undulating country of bare and desolate aspect. This impression 
is to a great extent produced by the prevailing sombre greyness of 
the hills, and their comparative freedom from vegetation of any 
kind; but as we become more closely acquainted with the 
country, we find that it is by no means of the barren nature our 
