284 JklETEOROLOGY IX RUSSIA. 



Ural Mountains to Lake Baikal was discussed last year by a special 

 commission of the Eussian geographical society, and the importance of 

 this work clearly pointed out. The council of the society, however, 

 declined to undertake the work immediately for want of adequate 

 means, yet it was hoped that private individuals would help the society 

 in this important enteri^rise, the more so as it has a practical bearing. 

 A line of railroad from Xijny-Xovgorod over the Ural to Irkutsk, 

 ftnd from thence to the Amoor Siver, or directly to China, is in serious 

 contemplation. Its feasibility is beyond doubt, as the difficulties are 

 far from being so great as those of the American Paciiic Eailroads. 



The barometrical minima have an important bearing on the produc- 

 tion of storms, as it is now well ascertained that these violent commo- 

 tlous of the atmosphere are caused by a great barometrical diflerence 

 between places near each other. Generally the barometer is very low in 

 the center of a storm, this center drawing in from every direction the 

 surrounding air. On the other hand, a great barometrical depression 

 can only be sustained by the condensation of vapor ; cold and dry con- 

 tinental areas will then arrest the progress of storms moving towards 

 them. The coldest region of Siberia can have no storms in winter, if 

 the foregoing views are correct. This is also the case; for example, at 

 Il^ertschinsk, we find scarcely a moderate wind in the three winter 

 months, calm or very light northwest winds being the rule. In West- 

 ern Siberia calms prevail in very cold winter mouths, while the winds 

 are stronger in warm winters. In considering European winter storms, 

 *Mohn arrives at the following conclusions: 



Storm-centers move from S. 71° "W. in the Arctic and Atlantic 

 Oceans, from X. 7^ W. in Scandinavia and Germany, and from X. 27^ 

 W. in Russia. He says that the air is too cold and dry in Northern and 

 Eastern Eussia to sustain the barometrical depression ; the condensation 

 on the southern side is much greater, and so the storm moves south- 

 ward, while the barometer rises in its center. The mean pressure in 

 the center of storms is 28.68 inches over Scandinavia and Germany, 

 and 29.13 over Eussia. 



Mohn has not attempted to trace the European storms to Siberia, as 

 the observations were too few for this purpose. I have tried to gain 

 some knowledge of the subject of storms by considering the barometri- 

 cal range ; that is, the mean maxima and miuima of each month.f I 

 can, however, only briefly state the results: The mean barometrical 

 Hiinima of the winter months, reduced to sea-level, are : At Eeikiavik, in 

 Iceland, 72G millimeters, or 28.5 inches ; at Hammerfest, Xorway, 730 

 millimeters, or 28.7 inches ; at St. Petersburg, 737.3 millimeters, 29.0 

 inches. At Barnaul, (West Siberia,) 754.7 millimeters, or 29.7 inches ; 

 at Xertschiusk. (East Siberia,) 7G3 millimeters, or 30.04 inches. In 

 the last-mentioned place, the mean barometrical miuima are an inch and 



' In his ••Srorm-Atlas." 



t Zeitscbrift der osterreichischen Gesellschaft fiir Meteorologie, year 1871, p. 161. 



