Ready reckoner
1990
Ready reckoner (weights and measures)
1972-1976
Arithmetical medal and numerical pocket piece
1753
"McFarlane's Calculating Cylinder" (c. 1833)
1833
"The Model Ready Reckoner"
1867
"The Readiest Reckoner in miniature"
1824
Robertson's 'Rapid Calculator', c 1910.
1910-1920
Bate's ready reckoner
1824
"The Banker's Sure Guide or Monied Man's Assistant"
1791
Equation of Time Calculator, French, 1816
1816-1821
The 'Tachylemme' ready reckoner, c 1876.
circa 1876
Parker's Prestometer Tablet, mid 19th century
circa 1860
Klinkerfues ready reckoner calculator for psychrometers, 1870-1876
1870-1876
Aristo 10076 chemist conversion ready reckoning rule for temperature
1970-1975
Battenburg's speed and distance scale by Elliott Bros.
The 'Multiplicateur Enfantin' ready reckoner, c 1880.
1876-1884
White & Bean's area scale on transparent celluloid
1907
The "Proell" pocket calculator
Scherer's "Logarithmischgraphische Rechentafel"
1880-1892
Ready reckoner (musical)
1785-1790
Aristo 10075 dyers ready reckoning conversion rule for temperature
1970-1975
Seyler's coal calculator
1934
The 'Tachypoly Plasiasme' ready reckoner, 1880-1884
1880-1884
Blundell Rules Limited C24 'Cost & Profit Reckoner'
1955-1965
Circular ready reckoner calculator for pump pressure drop with various viscous fluids by Plenty & Son Limited
1960-1965
Circular A61 Re-order Point ready reckoner calculator
1965-1975
Ready reckoner with cursor
Gripalculator slide rule patent no.335379 of 1929
Hines' 'Patent Weight and Quantity Calculator', c.1908.
circa 1908
C.D. Indicator
Aristo 10075E dyers ready reckoning conversion rule for temperature
1970-1975
Three card slide rule ready reckoners by Omaro
1935-1939
Unit conversion slide rule and metric unit converter in slide-rule format
1975
"Toutechnique" protractor-calculator
McFarlane's calculating cylinder
Cullum's Calculator
Selection of four ready reckoners
1972-1976