S CIENTIFl C MIS CELL AN Y. 44 1 



in Crrcenland Bay near Koma, whence we deduce that those regions were 

 formerly covered by a rich vegetation. The ice period of the geologists ap- 

 peared, and in consequence of the sinking temperature that luxuriant vege- 

 tation was wrapped in a shroud of snow and ice. 



The temperature sinking, a phenomenon which extended from the Nortii 

 southwardly, and may be established b}'' evidence derived from geology, to 

 wit, by the discovery of fossil plants, seems also to be on the increase in our 

 days. Within the last few years the ice seems to have pressed on from the 

 ]N"orth Pole far southwardly, as for instance, colossal bodies of ice have been 

 accumulated between Greenland and the Arctic Ocean. On the European 

 coast mariners have come upon ice in latitudes where, in the milder season 

 they usually do not find any, and the cold weather on the Scandinavian 

 Peninsula this summer is derived from the bodies of ice floating about in 

 regions where the gulf stream bends in the direstion of our coasts. 



It is a repetition of the observation made in the cold summer of 1865. 

 That unusual vicinity of those bodies of ice made the climate of Iceland so 

 cold that the grain will no more ripen, so that, in view of threatening fam- 

 ine and cold, the Icelanders will have to establish a new home in Norht 

 America. It was the same in the fouoteenth century in Greenland, when 

 the ZSTorwegian colonies were destroyed by the bodies of ice pressing onward. 



BERLIN PNEUMATIC DESPATCH. 



The proposed pneumatic despatch line in Berlin will have 26 kilometres 

 of lube, and 15 initial stations. The wrought-iron tubes have a clear 

 breadth of 65 millimetres, and lie about one metre below the surface of the 

 ground. The letters and cards which are to bo forwarded have a pre- 

 scribed size, and are inclosed in iron boxes or cartridges, each of which can 

 hold 20 letters or cards. In order that they may pack closely, they are 

 covered with leather. From 10 to 15 cartridges are packed and forwarded 

 at a time ; behind the last cartridge is placed a box with a leather ruffle, in 

 order to secure the best possible closure of the tube. At four of the stations 

 are the machines and apparatus needed for the business. The forwarding 

 of the boxes is effected either through compressed or rarefied air, or through 

 a, combination of the two. Steam-engines of about 12 horse-power arc 

 used for the condensation or exhaustion of the air. Each main station has 

 two engines, which drive a compressing and an exhausting apparatus, the 

 steam for each engine being furnished by two boilers. Large reservoirs 

 are employed both for the condensed and the refined air. The former has 

 a tension of about three atmospheres ; the latter, of about 35 millimetres 

 of mercury. The air, which is heated to 45° C, by the compression, is 

 cooled again in the double-walled cylinders which are surrounded by water. 

 The velocity of the boxes averages 1000 metres per minute, and a train is 

 despatched every 15 minutes. Each of the two circuits is traversed in 20 



