What influence has the Gulf Stream on the climate of Europe?

Various opinions have been expressed as to this. It has been estimated
that the amount of heat arising from the stream on a winter's day, is
sufficient to raise the atmosphere over the British Isles from the
freezing point to a summer temperature.


How may the Gulf Stream be distinguished?

It can be distinctly traced in the ocean by its dark indigo color, its
temperature, and the swiftness of its waters.


Which is the largest tunnel in the world?

The Mt. Cenis Tunnel, or the tunnel of Col de Frejus, by both of which
names it is known. It is the longest subterranean route for commerce
and travel yet constructed, being 7-1/4 miles in length. It is on the
crest of the Cottian Alps, about 16 miles south-west of the summit of
Mt. Cenis Pass. It was begun in 1857, and finished in 1871.

_Col_, a defile.


What other great engineering work can you mention?

The Suez Canal, a ship canal running across the Isthmus of Suez, and