The rules on this page originally comprised two main categories. The first was alcohol rules used for calculating the quantity in a cask and/or the excise duty payable. The second was folding rules with a slide for ancillary calculations such as the carpenter’s rule (Coggeshall rule) and the Routledge engineer’s rule. More recently I have added a First World War artillery slide rule and a Thomlinson’s Equivalent Paper Slide.
Alcohol slide rule by J Long, London, made of boxwood and probably dating from the early twentieth century. Length 8¾ inches. The rule is almost certainly from a box containing a Sikes hydrometer, which it would have been used in conjunction with (see Miscellaneous instruments pages). It is a “Proof” slide rule for the calculation of percentage proof and is one of two types of slide rule for use with the Sikes hydrometer.
Alcohol slide rule by Joseph Long, 43 East Cheap, London. Long’s business (posthumous) was at this address from 1885 to 1936. This appears to be primarily a gauging rule for determining the content of casks whether standing or lying and also functions as a comparative rule.
Farrow & Jackson Ltd, London, spirit slide rule, probably ca.1900. Nine inches long, boxwood and brass.. This is the other type of slide rule found with Sikes hydrometers and is a “Comparative” slide rule.The upper face is used for costing and the lower face for reducing. Ref: Pierre Vander Meulen, Sikes’s Hydrometer and Related Slide Rules, Journal of the Oughtred Society Vol. 10 No. 1 Spring 2001 pp 30-34. I have another comparative slide rule by Sanders & Sons.
Carpenter’s slide rule by Bradburn, made of Boxwood and brass with steel end caps. George & Thomas Bradburn (18 Alcester Street, Birmingham) were rule makers working 1841-52. A two foot, two-fold rule.
Carpenter’s slide rule by J Rabone & Sons, Birmingham. A boxwood and brass, three foot, four-fold rule, probably dating from the early twentieth century.
Routledge engineer’s slide rule by S A Smith, made of boxwood and brass with steel end caps. It has been repaired, many years ago, with riveted on nickel silver plates. Samuel Albert Smith (Coventry Road, Birmingham) was working from 1850 to 1862.
Applied Observation of Fire Slide Rule Mk VI made by J A Nicholl & Co of London in 1916. The rule is made of aluminium with brass end pieces. The body of the rule is 16” long. When purchased it was minus cursor and a replica of the brass cursor has been made using the scans of a similar rule in Herman van Herwijnen’s archive on Rod Lovett’s website as a reference.
Thomlinson’s Equivalent Paper Slide. This mahogany and boxwood slide rule is 585 mm long and has two slides. The scales are lettered A to E from top to bottom. Scales A & B in conjunction with C enable the area of a sheet of paper to be calculated. Scales D and E are concerned with calculating the weight of a ream of paper using either standard sizes given on scale E or the size calculated using scales A to C. Reams of 480, 500 and 516 sheets are catered for. J Thomlinson Lm, Publishers, Partick, Glasgow.
Hudson’s Pump Duty Computing Scale, made by W F Stanley, London, late 19th or early 20th century. A celluloid faced wooden open frame slide rule with nickel silver end braces and two slides. It has a Morocco leather covered, card slip case. The scales are: discharge in cubic feet, discharge in gallons, stroke feet & inches, efficiency (single acting & double acting), time pumping, revolutions or double strokes per minute, inches diameter of barrel. The last scale is in three sections over two lines. If the lower line is used then the result has to be either multiplied or divided by ten. J G Hudson C.E. also invented a horsepower computing rule (for steam engines), a shaft & girder slide rule, and a photographic exposure calculator, all of which were also made by Stanley. These scales were all made in a variety of materials including card, opaque celluloid, and ivory.
Carpenter’s slide rule signed ‘J Aston Maker Warranted Best Box’, made of boxwood and brass with steel end caps. John Aston was one of a number of rule makers named Aston working in Birmingham in the 19th century. A two foot two-fold rule. I originally thought it was by Isaac Aston of London.
Another, different, carpenter’s slide rule by John Aston, Birmingham (working 1854-82). Two foot two fold boxwood slide rule with brass slide and outer hinge plates. Steel end caps and inner hinge plate. Double radius log scales on rule and slider, girt line scale, ¼, 3/8, ½, 5/8, ¾, inch plain scales, twenty four inch ruler on reverse plus 12” on reverse of slide, E & M scales. The latter (edge and middle) scales were used to set out an octagon when rounding timber for masts, etc.
John Rabone and Son Warrant Boxwood, Vulcan hinged, carpenter’s two foot two fold slide rule dating from 1869-77. Probably a no. 2421. The registered design diamond for 13 Oct 1869 refers to the Vulcan hinge . Besides the ruler scales it has on the upper front the usual A{B,C}Girt Line scales, on the lower front 5/8 and inch draughtsman’s scales, and on the reveres 8 Square and Line scales. There is a decimal foot ruler on the upper edge and the lower one is bevilled (Spelling in the 1878 John Rabone & Sons catalogue).
Farmar’s Rule, The Standard Slide Rule for the Entire Wine & Spirit Trade (Desk Size). Farmar held a number of patents for alcohol slide rules. This twenty inch long duplex slide rule, mahogany faced with celluloid, with brass end bridges carried out a comprehensive range of functions including reducing, gauging, and calculating profit on sales. The cursor is celluloid screwed to wood. Early twentieth century.
Another similar alcohol slide rule by Joseph Long, 43 East Cheap, London, but this one is ivory and nickel silver. The scales are A{B}Segt St{N}Seg Ly//D{C}E{Proof}F. There are also three gauging scales on the upper edge for different shapes of cask, including SPED (spheroid) and 2nd Variety. The scales are the same as on the boxwood and brass version. It dates from the same period.
Farmar’s Wine & Spirit Merchant’s Rule, The Standard for the Entire Trade. Boxwood and brass slide rule, 23 inches long with 24 inch slide. Basically the same scales as the rule above, but lower prices because of the earlier date. Extra ‘Altimeter’ scale on one edge. ‘Size 1 (1610)’ on the other.. Early twentieth century.
Dring & Fage, 145 Strand, London, alcohol slide rule made for the Inland Revenue. This 24 inch rule is single sided with just four scales: A{B,B}Seg Ly. Boxwood with brass end bands. Made between 1883 & 1902.
Alcohol slide rule by Cock, London with four slides, two each side, made of boxwood and dating from about 1830 to 1840. Length 9 inches. The rule came from Kemp Town Brewery, Brighton when the brewery closed after take-over by Charringtons.
Gauger’s slide rule of the Everard type, probably from the 2nd half of the 18th century and certainly pre-1824 as it has the gauge points for the old wine gallon and ale gallon. The undersides of the four slides, shown in the bottom picture are also graduated, two being for various shapes of cask (variety 2, 3, spheroid, cone).
Gauger’s slide rule, open frame type with two slides, approximately nine inches long. The scales on the front and back faces are the same as on the Cock slide rule above but the four sets are arranged in a different order. There are scales on the edges (not shown). On one edge there are scales for spheroid and 2nd variety (not named) and on the other edge is a single radius log scale and an adjacent similar scale displaced by 1.6. The scales on the faces are: A{B,B}SL./A{C,C}MD//D¹{B,B}D²/A{C,C}SS. SL = Segment Lying, SS = Segment Standing, MD = Malt Depth. Scale. D¹ and D² are the two halves of an 18 inch long log scale. The first half is not labelled and the second half is labelled ‘D’. Because it has IMB and IMG gauge points it must date after 1824 and it must be earlier than 1880 as it has the malt depth scale. I would date it about 1850-1860. It is boxwood and brass with brass pins inset at the gauge points.
This Head Rod is actually ca.1968 but I have placed it here to be with the other alcohol slide rules. It is 50 inches long and is actually a prototype metric version with the measuring scale reading to 124 cm. It is both a measuring instrument (to measure the head diameter (the projecting brass feet enable it to measure inside the chimes) and a slide rule to calculate the volume inside the cask, both full and part full. The left enlargement shows the scale marked SPH’D (spheroid); the adjacent unmarked scale will be ‘2nd variety’ being different shapes of cask. The right enlargement shows the ullaging scales on the other side of the rule marked A{B,C}Seg Ly. Made by Dring & Fage, overtaken by the digital age, only a few prototypes made.
Mannheim type slide rule by A Franks of Manchester (presumably the retailer). It appears to be boxwood with a folded celluloid cursor. It has pasted on tables on the reverse and a black card case. Scales are: A(B,C)D.