4.3 Years 1910-1919

Number of slide rules: 25.

Variations in scale arrangements continued. See, for example, Dietzgen’s 1759-B with its R scale. Metal slide rules made their entrance in the U.S. during this decade as well. The Reitz scale arrangement was developed in Germany, which included K and L scales on the front with trig scales on the back of the slide. The K&E duplex models that include log-log scales for advanced calculations begin to gain popularity during this decade.

Some notable technical developments: air conditioning invented; World War I; nucleus of atom discovered.

Year Maker Model
1910-1912 Dietzgen 1761-AL
1910-1914 K&E 4053-2
1910-1914 K&E 4053-3
1910-1921 Dietzgen 1760-B
c.1912 Richardson Direct Reading (812)
c.1912 Richardson Pantocrat 812
c.1912 Richardson 1776
c.1912 Richardson Direct Reading Pocket
c.1912 Richardson Direct Reading Pocket
1913 Dennert & Pape No. 9
1913 K&E 4092
1913-1922 K&E 4133
c.1915 K&E 4058
1915-1921 K&E 4041
1915-1922 K&E 4100
c.1916 K&E 4083
1916-1920 K&E 4088-2
1916-1922 K&E 4088-3
1916-1925 K&E 4058 (student)
1917-1918 Richardson Model of 1917
c.1918 Richardson GE Analizer
1919 Gilson Midget
1919 KHH Pocket Rule
1919-1927 Dietzgen 1759-B
1919-1927 Dietzgen 1759-B