On verso: Dates on which of killing frost in spring falls to 10 per cent -- Dates of which the chance of killing frost in fall rises to 10 per cent -- Number of times in the 20 years 1895-1914 the last killing frost in spring was 10 days or more later than the average date -- Number of times in the 20 years 1895-1914 the last killing frost in spring was 10 days earlier thant the average date.; Includes first killing frost in fall 1914 (inset map), occurrences of first killing frost in fall (chart).; Relief shown by hachures. 39 x 59 centimeters Scale 1:8,000,000 General Map Collection