PROGRESS OF METEOROLOGY IN 1889. 217 



soil has beeu frozea to a great depth, a rai)id thaw, setting iu in the 

 spring, Hoods the rivers and the surrounding tracts, while little or 

 none enters the ground, and but little supply is stored up for main- 

 taining the summer flow. {Nature, XL, p. 315.) 



Greenland Exploration. — At a meeting of the Eoyal Geographical 

 Society, Dr. F. Nansen told the story of his journey across Greenland in 

 the summer and fall of 1888. He fonnd the country so thickly covered 

 with the ice accumulations of ages that no part of the interior is ever 

 laid bare. This will put to rest the idea that somewhere iu Greenlan<l 

 there may be a fertile oasis. He estimates that the ice in places is G,000 

 feet deep. The temperature during the expedition reached 90° F below 

 freezing, which was as low as their thermometer registered. 



ISecular OseiUations in Climate. — 11. Sieger has added some new and 

 important coutribntious to the statistics showing long period oscilla- 

 tions in the level of inland seas. That such variations iu level have 

 occurred was pointed out by Uann as early as 1807, and during the past 

 two years has also been elaborately discussed by Dr. Briickner. 



The work of Sieger relates to the level of the Armenian lakes. The 

 material available for such an investigation consists, not of exact obser- 

 vations of water level, but of opportune notes of individual travellers, 

 upon the location of places on the seashore, the course of the shore- 

 line, the appearance of islands, and finally upon the oscillation of the 

 water surface, derived from the statements of the neighboring inhab- 

 itants. 



From this heterogeneous material the author endeavors to show sec- 

 ular oscillations in the level of Armenian lakes, especially the Wan, the 

 Urmia Goktscha, and also a series of smaller lakes, and attributes the 

 cause of these oscillations to oscillations iu temperature and rain-fall. 

 Similar secular variations of level ^ire adduced for lakes in Iran, in the 

 Alps, and in Italy, and for Lake Valencia, Honey Lake, Pyramid Lake, 

 Winnemucca Lake, and the Great Salt Lake of Utah. 



The times of maximum and minimum of level are grouped about the 

 following well-defined i)eriods : (1) Maximum between 1770 and 1780; 

 (2) minimum about 1800 (not pronounced); (3) maximum about 1815; 

 (4) minimum about 1830 ; (5) between 1835 and 1865 a series of lakes 

 has two maxima, a minor about 1845 and a major about 1860; these are 

 the Armenian lakes. Lake Constance, Lake George in Australia, Great 

 Salt Lake, and some of their neighbors. The remaining, on the other 

 hand, show only a maximum about 1845; (G) a minimum iu the sixties, 

 1800-1870; (7) a rise from 1865 to 1870, followed by an interruption 

 beginning with 1870; (8) a diminution after 1880. 



In a memoir entitled " In how far is our present climate permanent ? " 

 Prof. Dr. Briickner brings together a store of data from various sources 

 which gives evidence of well-defined oscillations in rain-fall and temper- 

 ature, oscillations having a period of no definite length, but averaging 

 during the present century from thirty to thirty-six years. The author 



