Accession No
6054
Brief Description
Fisher statistical slide rule in plastic case with instruction manual and book of tables; English; circa 1967
Origin
St. Paul’s House, Warwick Lane London, EC4, England; Weymouth, England
Maker
University of London Press Blundell Rules
Class
mathematics; calculating
Earliest Date
1967
Latest Date
1967
Inscription Date
Material
plastic; paper
Dimensions
length 266mm; breadth 102mm
Special Collection
Provenance
Donated on or before 23/09/2004.
Inscription
‘The Fisher Statistical Slide Rule
© Gerald H Fisher 1965’ (on reverse and on plastic case)
‘Blundell Rules Ltd. Weymouth England’ (bottom right of front of slide)
Description Notes
Fisher statistical slide rule in plastic case with instruction manual and book of tables; by the University of London Press Ltd / Blundell Rules Ltd; English; circa 1967
front of the slide is printed with six scales for probability tests ‘t, F, r, ρ, τ and χ2 ’ and colours for one tail and two tailed probability levels. cursor has windows and a key for the colours (green, p > .05; yellow .05 > p > .01 ; red, p < .01)
reverse of slide is printed with the standard normal distribution function, windows for ‘z, y, p (one tail), p (two tail)’ and percentage areas.
black plastic case with instruction booklet.
‘The New Form Statistical Tables’. A4 sized spiral bound book; blue-green cover.
Condition: good; complete
References
Events
Description
Developed during the seventeenth century, the modern slide rule is based upon the design by William Oughtred (circa 1630). It is one of many calculation devices that is based on the logarithmic scale, a calculation method invented in 1614 by John Napier.
Before the rise of the pocket electronic calculator in the 1970s, the slide rule was the most common tool for calculation used in science and engineering. It was used for multiplication and division, and in some cases also for ‘scientific’ functions like trigonometry, roots and logs, but not usually for addition and subtraction.
Calculations are determined by aligning a point along the central movable strip with a mark on one of the scales on one of the two fixed strips, and then observing the relative positions of other points along the scales. A logarithm transforms the operations of multiplication and division to addition and subtraction according to the rules log(xy) = log(x) + log(y), and log(x/y) = log(x) - log(y). Moving the top scale to the right by a distance of log(x) aligns each number y, at position log(y) on the top scale, with the number at position log(x) + log(y) on the bottom scale. Because log(x) + log(y) = log(xy), this position on the bottom scale gives xy, the product of x and y.
FM:46522
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