paragon compensating polar planimeter
Datecirca 1960
Inventory Number1997-1-2000
ClassificationPlanimeter
Subject
Attributed to
Gebrüder Haff
1835-present
Supplier
Keuffel & Esser Company
1867 - 1987
Owner
Benjamin Martin Shaub
1893 - 1993
Cultural Region
Place of Origin
Dimensions4.3 × 25.2 × 9.1 cm (1 11/16 × 9 15/16 × 3 9/16 in.)
Material
Accessoriesblack storage case
two white cards with conversion tables inside case
DescriptionThe planimeter is stored in a black rectangular case that opens with two hinges along a long edge. There are two metal clips on the lid of the case that snap onto two metal pins attached to plates on the front of the bottom half of the case. The inside of the case is lined with blue velvet. The bottom half of the case is contoured to fit the pieces of the instrument. There is a white card inside the case with instrument and conversion information.
The planimeter breaks down into two main pieces with four accessories. One main piece is a long, rectangular, silver metal bar inside a sliding black metal sleeve of shorter length. There is a metal screw at one end of the black sleeve that can be loosened to permit the sleeve to slide and tightened to hold it in place. At one end of the black metal sleeve, there is a large, brass metal puck. At the opposite end of the silver metal bar, there is a metal pin.
The second main piece is also a long silver metal bar, called the tracer arm. It has three short black metal sleeves, each attached to a black metal framed measurement mechanism. The measurement mechanism consists of two parts. First, there is a flat white disc with incremental measurements from 0 to 9 marked around the circumference. The disc lies flat. There is a black arrow that is attached to the black frame at one end and whose the other end lies flat on the disc pointing to the measurements. Beneath the disc, parallel to the main bar, there is a thick, silver metal screw. The second device in the measurement mechanism consists of a wheel and the subsection of a wheel, both white with black markings. The axis of both runs parallel to the metal bar and connects with the metal screw beneath the white disc. The wheel is incrementally marked with the numerals from 0 to 9, and each increment is further subdivided into 10 sections. The wheel subsection has a single unit, one end marked "0" and the other marked "10" with 10 equally spaced lines between them. The wheel subsection serves to increase the accuracy of the readings made on the wheel. The leftmost black sliding sleeve (when the company name is right side up) also has a silver metal roller attached to it, extending away from the bar in the opposite direction to the measurement apparatus. The rightmost black sliding sleeve on the bar has a screw through it. When loosened, the black framed measurement mechanism can slide along the bar and when tightened, it is held in place. The center black sliding sleeve has a hole in the top.
At the leftmost end of the metal bar, there is a silver metal screw extending above and a silver metal stylus extending below. There is also a rotating black metal finger hold. The proper way to use the planimeter is to put thumb and middle finger in the depressions on either side of the finger hold and pointer finger atop the screw in order to guide the stylus along the figure below.
There are incremental measurements engraved in the silver metal bar with the sliding measurement apparatus. They begin with 5 at the leftmost end and increase by 1s up to 36 at the rightmost end. Each increment is further subdivided in 10 by small engraved lines. When the instrument is assembled, the silver metal pin at one end of the longer metal bar sits in the hole through the top of the central black sliding sleeve.
Three of the four accessories accompanying the main instrument are flat, rectangular strips of metal. Two of the strips are engraved with incremental measurements engraved from end to end. One set of engravings proceeds as follows: 0, 3, 6, 4, 2, 0 and the other proceeds as follows: 0, 3", 2", 4", 0. Each of these strips has a black screw at the end of the 0 last in these lists and has a slight narrowing and bend at the opposite end. The third strip has no measurements but has a small hole punched through one end. The fourth accessory to the instrument is a long, thin metal pin bent into the shape of a 'V' with a flattened bottom. One end of the pin is sharp and pointed, the other is blunt.
The Keuffel & Esser Co. Manual for compensating polar planimeters that details the design and function of the instruments can be found here. Pages 13 - 14 deal specifically with this model, the 4242 and the 4242 1/2.
The planimeter breaks down into two main pieces with four accessories. One main piece is a long, rectangular, silver metal bar inside a sliding black metal sleeve of shorter length. There is a metal screw at one end of the black sleeve that can be loosened to permit the sleeve to slide and tightened to hold it in place. At one end of the black metal sleeve, there is a large, brass metal puck. At the opposite end of the silver metal bar, there is a metal pin.
The second main piece is also a long silver metal bar, called the tracer arm. It has three short black metal sleeves, each attached to a black metal framed measurement mechanism. The measurement mechanism consists of two parts. First, there is a flat white disc with incremental measurements from 0 to 9 marked around the circumference. The disc lies flat. There is a black arrow that is attached to the black frame at one end and whose the other end lies flat on the disc pointing to the measurements. Beneath the disc, parallel to the main bar, there is a thick, silver metal screw. The second device in the measurement mechanism consists of a wheel and the subsection of a wheel, both white with black markings. The axis of both runs parallel to the metal bar and connects with the metal screw beneath the white disc. The wheel is incrementally marked with the numerals from 0 to 9, and each increment is further subdivided into 10 sections. The wheel subsection has a single unit, one end marked "0" and the other marked "10" with 10 equally spaced lines between them. The wheel subsection serves to increase the accuracy of the readings made on the wheel. The leftmost black sliding sleeve (when the company name is right side up) also has a silver metal roller attached to it, extending away from the bar in the opposite direction to the measurement apparatus. The rightmost black sliding sleeve on the bar has a screw through it. When loosened, the black framed measurement mechanism can slide along the bar and when tightened, it is held in place. The center black sliding sleeve has a hole in the top.
At the leftmost end of the metal bar, there is a silver metal screw extending above and a silver metal stylus extending below. There is also a rotating black metal finger hold. The proper way to use the planimeter is to put thumb and middle finger in the depressions on either side of the finger hold and pointer finger atop the screw in order to guide the stylus along the figure below.
There are incremental measurements engraved in the silver metal bar with the sliding measurement apparatus. They begin with 5 at the leftmost end and increase by 1s up to 36 at the rightmost end. Each increment is further subdivided in 10 by small engraved lines. When the instrument is assembled, the silver metal pin at one end of the longer metal bar sits in the hole through the top of the central black sliding sleeve.
Three of the four accessories accompanying the main instrument are flat, rectangular strips of metal. Two of the strips are engraved with incremental measurements engraved from end to end. One set of engravings proceeds as follows: 0, 3, 6, 4, 2, 0 and the other proceeds as follows: 0, 3", 2", 4", 0. Each of these strips has a black screw at the end of the 0 last in these lists and has a slight narrowing and bend at the opposite end. The third strip has no measurements but has a small hole punched through one end. The fourth accessory to the instrument is a long, thin metal pin bent into the shape of a 'V' with a flattened bottom. One end of the pin is sharp and pointed, the other is blunt.
The Keuffel & Esser Co. Manual for compensating polar planimeters that details the design and function of the instruments can be found here. Pages 13 - 14 deal specifically with this model, the 4242 and the 4242 1/2.
Signedin gold lettering on the instrument case: KEUFFEL & ESSER CO. N.Y.
engraved in white lettering on instrument arm: KEUFFEL & ESSER CO NY / GERMANY
Inscribedin gold lettering on instrument case: 4242
punched on brass wheel: 11
engraved in white lettering on instrument arm: No. 6711
punched on metal roller: No. 6711
FunctionThe polar planimeter is used for ascertaining the area of any plane surface represented by a figure drawn to any scale, such as indicator diagrams, profiles, architectural plans or sections. The planimeter is placed over top of the diagram in question and the user traces it with the stylus at the end of the tracer arm. The planimeter measures the area of the traced figure. This particular model of planimeter was useful for terrain analysis, cut and fill procedures, and hydrology.
This is a polar planimeter because the intersection point of the tracing arm and the second arm is restricted to circular motion. This is the case because the other end of the second arm is fixed in place by the weight of the brass puck. For linear planimeters, the end of the tracer opposite the stylus moves in a straight line, either in a track or on rollers.
This model of compensating polar planimeter is further improved by the user's ability to adjust the relative placement of the two arms. The measurement mechanism on the tracing arm can be slid to any desired measurement along it changing the placement of the hole into which the second arm sits. Further, the placement of the weighted end of the second arm changes as the longer black sleeve is slid along the arm.
As the user traces a figure on the surface below, the metal roller attached to the tracing arm rolls and slides along accordingly. The measurement mechanisms record this motion and when the user arrives back at the starting point, the recorded motions will be proportional to the area of the figure below.
The Keuffel & Esser Co. Manual for compensating polar planimeters that details the design and function of the instruments can be found here. Pages 13 - 14 deal specifically with this model, the 4242 and the 4242 1/2.
This is a polar planimeter because the intersection point of the tracing arm and the second arm is restricted to circular motion. This is the case because the other end of the second arm is fixed in place by the weight of the brass puck. For linear planimeters, the end of the tracer opposite the stylus moves in a straight line, either in a track or on rollers.
This model of compensating polar planimeter is further improved by the user's ability to adjust the relative placement of the two arms. The measurement mechanism on the tracing arm can be slid to any desired measurement along it changing the placement of the hole into which the second arm sits. Further, the placement of the weighted end of the second arm changes as the longer black sleeve is slid along the arm.
As the user traces a figure on the surface below, the metal roller attached to the tracing arm rolls and slides along accordingly. The measurement mechanisms record this motion and when the user arrives back at the starting point, the recorded motions will be proportional to the area of the figure below.
The Keuffel & Esser Co. Manual for compensating polar planimeters that details the design and function of the instruments can be found here. Pages 13 - 14 deal specifically with this model, the 4242 and the 4242 1/2.
ProvenanceUsed by Prof. Benjamin M. Shaub, Department of Geology, Smith College, Northampton, MA 01063. Prof. Shaub gifted a total of 11 instruments to the Collection, inventory #s 1997-1-1997 thru 1997-1-2007.
G. Coradi
Date: circa 1911
Accessories: conversion table on white card in instrument case; instrument case
Object number: 1999-1-0068
Gebrüder Haff
Date: circa 1940
Accessories: card with instrument info and conversion table; photocopy of letter from Dr. Joachim Fischer to William J.H. Andrewes, dated 12 May 1997; photocopy of extract from Dr. Joachim Fischer's inventory of integrating instruments included with the letter
Object number: 1997-1-0444
Gebrüder Haff
Date: circa 1940
Accessories: card with instrument information and conversion table
Object number: 1997-1-0445
Gebrüder Haff
Date: circa 1940
Accessories: case
Object number: 1997-1-0446
Gottlieb Coradi
Date: circa 1920
Accessories: pieces of the front of black leather case with clasps; lid of case with paper data sheet; pieces of black leather case lined with green velvet
Object number: 2004-1-0345
Gebrüder Haff
Date: circa 1949
Accessories: instruction manual for K&E planimeters 4236, 4236M and 4242 in instrument case; instrument case; green cardboard box for instrument case; white card with instrument information inside case
Object number: 2004-1-0346
Gebrüder Haff
Date: circa 1957
Accessories: white card with instrument information inside case
Object number: 1997-1-0447
Gebrüder Haff
Date: circa 1949
Accessories: instrument case
white card with instrument and measurement information inside instrument case
Object number: 2004-1-0344
Gebrüder Haff
Date: 1960-1969
Accessories: plush-lined, hard green case
white card with instrument information in case
Object number: 1999-1-0005
Crosby Steam Gage & Valve Company
Date: circa 1910
Accessories: original and photocopy of letter from Dr. Joachim Fischer in Berlin requesting information and photographs of mechanical integrating devices from William J.H. Andrewes, dated 13 October 1993
photocopy of letter from William J.H. Andrewes to Dr. Joachim Fischer, providing information on the planimeter and requesting details for his desired photographs; original and photocopy of letter from William J.H. Andrewes to Dr. Joachim Fischer, responding to a request regarding mechanical integrators acquired from the Aiken computer laboratory, dated 11 April 1997; letter from William J. H. Andrewes to Dr. Joachim Fischer that accompanied the photographs, dated 26 April 1995; film and eleven color photographs of the instrument, probably copies of those sent to Dr. Joachim Fischer
Object number: 1995-1-0003
Jakob Amsler
Date: circa 1906
Accessories: instrument is in four (4) parts; the rail is in own box and is inventory # 2006-1-0002b; letter from Prof. William Brower containing the complete history of ownership and use (missing)
Object number: 2006-1-0002a