Forel, Handbuch der Seenkunde: allgemeine Limnologie (Stuttgart, 1901); F.
The northern seas have an increasing tendency towards green, the Irminger Sea showing 5-9 Forel, while in the North Sea the water is usually a pure green (io-14 Forel), the western Mediterranean shows 5-9 Forel, but the eastern is as blue as the open ocean (0-2 Forel).
A pure blue colour has been observed in the cold southern region, where the " Valdivia " found o-2 Forel in 55° S.
The blue of the sea-water as observed by the Forel scale has of course nothing to do with the blue appearance of any distant water surface due to the reflection of a cloudless sky.
Forel, Documents concernant l'ancien eveche de Lausanne, 2 parts (Lausanne, 1846-1847); J.
From 1769 to 1887 there were 10 " destructive " and 24 other " extremely severe " shocks according to the Rossi Forel nomenclatural scale of intensity.
Forel, " La Limnologie, branche de la geographie," Report VI.