192 | REVIEWS 
in Sweden, at the latest minimum and maximum of inclination, respec- 
tively gtoo and 28,300 years ago, thus: 
28,300 years ago - - 38 days 
g,100 years ago - - - 62 days 
At present 5 < = 54 days 
Then follow tables showing calculated temperatures (in terms of excess 
and deficiency compared with the present) for different latitudes dur- 
ing the months of the year at the last maximum (28,300 years ago) and 
the last minimum of inclination (g100 years ago) north of 80° N. lati- 
tude. There was, 28,300 years ago, a deficiency of 5° C. In Sweden 
the deficiency was from 3%° to 2° C. These figures are all for the 
summer months. The author is uncertain as to the winter tempera- 
tures. In Sweden these would perhaps depend on the gulf stream, as 
at the present; g100 years ago the summer heat was 2° to 1.3° C. higher 
than now, while the winter temperature is uncertain. A time with 
hot summers occurred 48,000 years ago. Geologists know of no 
other period of greater heat than the present, except the one gooo 
years ago, sence the end of the last glaciation. ‘The end of the ice age, 
hence, cannot have occurred earlier than 50,000 years ago. Possibly 
it is later, but the greater summer insolation 48,000 years ago may have 
helped in melting the ice. 
The last section of the paper relates to climatological changes in 
historic time, especially in northwest Europe. ‘Yhe author discusses 
recorded observations on the forming and thawing of ice on various 
Scandinavian waters, ancient stock-raising in Greenland, grape culture, 
etc., and concludes that the winters have grown milder and the sum-’ 
mers cooler during the last 300 years. Some conclusions are drawn 
from a study of weather records made by Tycho Brahe. A compara- 
tive table of snow precipitation for Brahe’s time and the present is 
given as follows. 
PER CENT. OF DAYS WITH SNOW OUT OF TOTAL DAYS OF PRECIPITATION. 
Years Oct. Nov. Dec. Jan. Feb. Mar, Apr. 
1582-1597 (Time of Brahe) - 3 14 38. As 75 63 21 
1881-1898 (Present) - ee 16 37 48 53 46 19 
By comparing this table with current temperature, he finds that it is 
likely that 300 years ago February was 1.4° C. colder than now, March 
r° C. colder, and the other months differed either way by less than 
2s 
