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The network of great velocity lines has grown longer since the first commercial exploitation in Japan in 1964. We had to wait for the present decade to see new sections open up in Japan, West Germany, and France ; and the movement has not ended. A report of the situation of lines in exploitation and lines in construction for 1986 has been drawn up. The projects are numerous in already equipped countries like Japan and France, but also in other European States, the Soviet Union, and in North America. The decision to construct the tunnel undemeath the English Channel, and the need for a new transalpine railroad break through calls for the construction of lines which will naturally be conceived for great speeds. The case of the United States retains attention by the multiplication of projects pending, by the hesitations of which technique to adopt (a great velocity train or a magnetic levitation train), and by oppositions practising to retard the moment when a new concurrent will intervene in the market for transports. The saturation of expressways and airports, and the difficulty of discovering new sites for the latter near large towns are favorable factors for the great velocity train : this technique alone is capable today of answering a strong demand between two poles : daily traffic on the line from Tokaido reaches 350 000 passengers.

Two large glaciers of the northernmost part of Ellesmere island happen to be morphologically extremely different front alpine type of glaciers, notably by the great length of " bédières ", some special microforms such as cryoconite holes, microponds, microhumps and a mesoform : the ice pad. The three later forms are entirely original. The absence of lateral and front moraines also caracterise both of these glaciers.

The French confronted, with the Saharian riddle : their geographers, explorers and engineers (1830-1881). In 1830, the French knew next to nothing about the Sahara and until the middle of the XIXth century they will have to rest satisfied with the little information afforded them by the natives. The thrust southward will only begin after 1850 but by that time, they looked upon the desert more as an obstacle to conquer than as an area to occupy. Field marshal Randon, whose dearest dream was to open up business connections with the Sudan, sent forth military columns both to the Tuat and Ghadamès. The founder of saharian geography was Henri Duveyrier who visited the Tassili of the Ajjer, El Goléa, Ghat, the Fezzan and depicted the Hoggar without having seen it. After 1870, Largeau who never went further than Ghadamès and Soleillet who had to turn back in front of In Salah, were the two unhappy champions of the cause of pacific penetration. In those very days, Captain Roudaire set afoot the stupendous scheme of a saharian sea covering up the Chotts'area. In 1880, the French, encouraged by the American example in the Far-West, launched the idea of a transsaharian railway. Even if it met with ultimate failure, the Flatters'expedition contributed handsomely to the knowledge of the desert. It was not before the very end of the century that the French went beyond the point reached by Flatters on the confines of the Hoggar.