Accession No

2251

Brief Description

gauging slide rule, Leadbetter type, by I. L., English, 1767

Origin

England

Maker

I. L.

Class

calculating

Earliest Date

1767

Latest Date

1767

Inscription Date

1767

Material

wood (boxwood); metal (brass)

Dimensions

length 304mm; breadth 27mm; thickness 18mm

Special Collection

Provenance

Purchased from Turner and Devereux, London, 28/5/1976, who purchased it in Christie’s sale of clocks and instruments, 26/5/1976, Lot 16. Purchased with assistance a Grant-in-Aid administered through the Science Museum (PRISM).

Inscription

‘*I:L: 1767*’ (underneath slide on face B)

Description Notes

Face A, upper stock: single radius logarithmic scale marked ‘root’ and ‘d’ divided 1 - 10 numbered by 1; 1 -2 subdivided to 0.01, 2 - 3 subdivided to 0.02, 3 - 10 subdivided to 0.05. Brass studs marking gauge points for ‘WG’ (wine gallons), ‘AG’ (ale gallons), ‘MS’ (square malt bushels) and ‘MR’ (round malt bushel). Lower stock has triple radius logarithmic scale marked ‘cube’ and ‘E’ divided 1 - 1000 numbered 1, 2 ... 10, 2[0], 3[0], 100, 2[00], 3[00] ... 1000; 1 - 3 subdivided to 0.05, 3 - 8 subdivided to 0.1, 8 - 10 subdivided to 0.2, 10 - 30 subdivided to 0.5, 30 - 80 subdivided to 1, 80 - 100 subdivided to 2, 100 - 300 subdivided to 5, 300 - 800 subdivided to 10, 800 - 1000 subdivided to 20.

On the slider a scale marked ‘square’ and ‘C’ divided 1 - 10[0] numbered 1, 2, 3 ... 9, 1[0], 2[0] ... 10[0]; 1 - 2 subdivided to 0.02, 2 - 5 subdivided to 0.05, 5 - 10 subdivided to 0.1, 10 - 20 subdivided to 0.2, 20 - 50 subdivided to 0.05, 50 - 100 subdivided to 1. Also scale marked ‘root’ and ‘D’ divided as for scale on the upper stock.
Reverse of slider carries a scale of inches divided [24] - 36 numbered by 1 subdivided to 0.1 and scale of ‘gallons’ divided [1.6] - 3.6 numbered by 0.1 subdivided to 0.02.

Face B:
log scale divided 1 - 10[0] numbered 1, 2, 3 ... 1[0], 2[0] ... 10[0]; 1 - 2 subdivided to 0.02, 2 - 5 subdivided to 0.05, 5 - 10 subdivided to 1, 10 - 20 subdivided to 0.2, 20 - 50 subdivided to 0.5, 50 - 100 subdivided to 1. This line appears on the stock marked ‘A’ and twice on the slider marked ‘B’ and ‘Num’.
Brass gauge points inlet twice on scale A at ‘MB’ (for malt bushel), and ‘A’ for (ale gallon); points marked on scale B at ‘W’ (wine gallon).
On the stock a further log scale inverted divided [2.15] - [215] numbered and subdivided as before and marked ‘MD’ (malt depth).
Verso of slide calibrated with scale of inches divided [13] - [24.5] numbered by 1 subdivided to 0.1 with corresponding calibration [0.475] - [1.65] numbered by 0.1G subdivided to 0.01 (for gallons in an inch deep tub of that diameter)

Side A:
On the stock ullaging scales of segments ‘S:L’ (cask lying) and ‘S:S’ (cask standing) divided 1 - 100 numbered 1, 2, 3 ... 10, 20, 30 ...100; 1 - 5 subdivided to 0.1, 5 - 10 subdivided to 0.02, 10 - 100 subdivided to 1. Slide carries scale divided 1 - 10[0] numbered 1, 2 ... 1[0], 2[0] ... 10[0]; 1 - 10 subdivided to 0.1, 10 - 20 subdivided to 0.2, 20 - 50 subdivided to 0.5, 50 -100 subdivided to 1.

Side B:
scale of inches divided [0] - 12 numbered by 1 subdivided to 0.1.
Scale of ‘Spheroid’ divided [0] - [7.5] numbered by 1 subdivided to 0.1
Scale of ‘2d Variety’ divided [0] - [6.5] numbered by 1 subdivided to 0.1
Scale of ‘3d Variety’ divided [0] - [5.5] numbered by 1 subdivided to 0.1

Condition good (one corner splitting); complete

References

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