perspektomat P-40 pantograph
Date1950-1960
Inventory Number1999-1-0054
ClassificationPantograph
Subject
Maker
Forster
Cultural Region
Place of Origin
Dimensionscase: 11.8 × 112.8 × 11.9 cm (4 5/8 × 44 7/16 × 4 11/16 in.)
Material
Accessoriesspare ink cartridges; pen attachments
am auxiliary box containing small Allen wrench, scotch tape, extra parts, and storage instructions
DescriptionThe Pantograph is stored in a long, rectangular, brown wooden box. The thin lid is attached to the main part of the box with hinges along the long side of the rectangle. There are three hooks on the bottom part of the box that fit into three loops on the lid to keep the box closed.
The Pantograph is attached to a long rectangular track that is mounted on an aluminum base with orange rubber lining on the bottom to prevent slipping. The aluminum arms of the Pantograph are connected to three grey plastic wheels that role horizontally along the track. The Pantograph is attached to the track at one end only, the rest free to move on the adjacent surface. Hereafter, let the track be the 'back' of the Pantograph, and left and right sides be determined accordingly.
The arms of the Pantograph form two parallelograms and a triangle. Each point of intersection between arms is a pivot, giving the Pantograph eight points of motion transfer. In what follows, each parallelogram will be treated as a set of three arms instead of four: two always parallel arms and one connecting arm. The left out arm of each parallelogram is one of the three members of the other set.
The leftmost corner of the larger parallelogram (on the left) has a writing attachment into which a pen can be slipped. The attachment sits on a small orange wheel. When the pen is in normal position, it traces the motion of that point on the surface below. There is a long, skinny, clear, plastic, pneumatic tube attached to the writing attachment. At the end of the tube there is a small orange ball that, when squeezed, lifts the pen from the surface below, halting the writing. There is sliding attachment on the connecting arm of this parallelogram with a spot for an auxiliary stereo drawing attachment. The two parallel arms of the larger parallelogram are marked with ruled increments. The increments are measured in degrees. One of the ruled arms is attached to the track at the back of the Pantograph and serves to adjust the placement of the main drawing arm. The connecting arm with the auxiliary drawing implement is attached to the other ruled arm and that scale serves to adjust its placement. Both adjustments serve to alter the proportions of the motion transfer ratios.
The smaller parallelogram on the right has one similarly ruled arm: the parallel arm furthest from the track at the back. It sits on a small orange wheel fixed in the center. This orange wheel is slightly bigger than the one supporting the drawing mechanism. This arm serves as the scale for adjusting the placement of one adjustable end of the connecting arm.
The Pantograph is accompanied by a series of pen attachments of different colors along with spare ink cartridges in a plastic bag, and metal shaft with plastic cap, of unknown use, though it may be there to adjust the length of the pen, all stored in the storage box.
There is another box that contains a fine-point drawing attachment with rubber sheath on tip, spare tip embedded in clear casing and sticking into circular cork, spare strip of pneumatic tube, unopened Scotch tape, small Allen wrench, two following points in plastic bag, four pen-tip containers marked "Leroy Lettering Pen" in plastic bag, and a bag of hardened, cracked replacement pneumatic seals. There are also four other items, marked "stereo," of uncertain use: one bar of aluminum with three holes and a peg, one longer bar with three holes, connected with a long black metal rod with a hole at the end, and two black sheets of metal with pegs that fit (loosely) into the hole of the rod. The holes in the aluminum bars fit around the pegs on the base. There is an enclosed paper label, typed in German that translates as follows:
"Placing the Pantograph System in the long case: The front slider (on rail C) is set to 30 degrees, the other two sliders are loosened and pulled towards their end positions (approx. 50 degrees, not tightened!), where upon one can fold the system. In the Pantograph with stereo attachment one has to first loosen the two knurled screws of the second pneumatic. Then it is moved as far as possible to the left and tightened. (While in use, it has to be set between the two marks." Translator's note: "Pneumatic" refers to the bulb-operated pen holders.
The Pantograph is attached to a long rectangular track that is mounted on an aluminum base with orange rubber lining on the bottom to prevent slipping. The aluminum arms of the Pantograph are connected to three grey plastic wheels that role horizontally along the track. The Pantograph is attached to the track at one end only, the rest free to move on the adjacent surface. Hereafter, let the track be the 'back' of the Pantograph, and left and right sides be determined accordingly.
The arms of the Pantograph form two parallelograms and a triangle. Each point of intersection between arms is a pivot, giving the Pantograph eight points of motion transfer. In what follows, each parallelogram will be treated as a set of three arms instead of four: two always parallel arms and one connecting arm. The left out arm of each parallelogram is one of the three members of the other set.
The leftmost corner of the larger parallelogram (on the left) has a writing attachment into which a pen can be slipped. The attachment sits on a small orange wheel. When the pen is in normal position, it traces the motion of that point on the surface below. There is a long, skinny, clear, plastic, pneumatic tube attached to the writing attachment. At the end of the tube there is a small orange ball that, when squeezed, lifts the pen from the surface below, halting the writing. There is sliding attachment on the connecting arm of this parallelogram with a spot for an auxiliary stereo drawing attachment. The two parallel arms of the larger parallelogram are marked with ruled increments. The increments are measured in degrees. One of the ruled arms is attached to the track at the back of the Pantograph and serves to adjust the placement of the main drawing arm. The connecting arm with the auxiliary drawing implement is attached to the other ruled arm and that scale serves to adjust its placement. Both adjustments serve to alter the proportions of the motion transfer ratios.
The smaller parallelogram on the right has one similarly ruled arm: the parallel arm furthest from the track at the back. It sits on a small orange wheel fixed in the center. This orange wheel is slightly bigger than the one supporting the drawing mechanism. This arm serves as the scale for adjusting the placement of one adjustable end of the connecting arm.
The Pantograph is accompanied by a series of pen attachments of different colors along with spare ink cartridges in a plastic bag, and metal shaft with plastic cap, of unknown use, though it may be there to adjust the length of the pen, all stored in the storage box.
There is another box that contains a fine-point drawing attachment with rubber sheath on tip, spare tip embedded in clear casing and sticking into circular cork, spare strip of pneumatic tube, unopened Scotch tape, small Allen wrench, two following points in plastic bag, four pen-tip containers marked "Leroy Lettering Pen" in plastic bag, and a bag of hardened, cracked replacement pneumatic seals. There are also four other items, marked "stereo," of uncertain use: one bar of aluminum with three holes and a peg, one longer bar with three holes, connected with a long black metal rod with a hole at the end, and two black sheets of metal with pegs that fit (loosely) into the hole of the rod. The holes in the aluminum bars fit around the pegs on the base. There is an enclosed paper label, typed in German that translates as follows:
"Placing the Pantograph System in the long case: The front slider (on rail C) is set to 30 degrees, the other two sliders are loosened and pulled towards their end positions (approx. 50 degrees, not tightened!), where upon one can fold the system. In the Pantograph with stereo attachment one has to first loosen the two knurled screws of the second pneumatic. Then it is moved as far as possible to the left and tightened. (While in use, it has to be set between the two marks." Translator's note: "Pneumatic" refers to the bulb-operated pen holders.
Signedengraved on pantograph arm in black letters: FORSTER SCHAFFHAUSEN / SCHWEIZ
Inscribedengraved on pantograph arm in black letters: PERSPEKTOMAT P-40
Curatorial RemarksWidth is length of arms when stretched out. Length is length of rail. Date was approximated from the logo font on the included scotch tape.
FunctionPantograph is a motion transfer mechanical linkage used to make re-scaled but otherwise identical copies of two dimensional drawings and maps. Users place the adjustable arms at the required scaled positions to produce the desired scale. Users then trace the original two-dimensional image and motion will be transferred through the instrument such that the drawing implement will draw the desired re-scaled image on the surface below.
Historical AttributesJames Burleigh Thompson, Jr., Sturgis Professor of Geology Emeritus (came to Harvard in 1949), found it in the Department when he moved into Room 200 of the Geological Museum, sometime after 1971. Decided to donate it upon moving from Room 200 to Room 211b. Might have been used by Hugh E. McKinstry, Professor of Geology from 1945 until his death in 1961. Obsolete by the time Prof. John Haller joined the department in 1964.
Adrien Gavard
Date: circa 1860
Accessories: hinged mahogany case with original trade label; extra arm; writing implements; instrument weights; small ivory wheels with brass frames
Object number: 1997-1-1856
Zeiss-Aerotopograph
Date: circa 1950
Accessories: in wooden storage case with metal handles; documentation booklet is now kept in the instrument's file; all other accessories are kept in the box and are included in the description.
Object number: 2009-1-0002b
Charles Thurber
Date: circa 1860
Accessories: wooden framed, glass paned case; original and photocopied letter from the Massachusetts Historical Society Director, Stephen T. Riley to David P. Wheatland dated June 28, 1961regarding permanent loan of the pantograph (in instrument file); original and photocopied hand-written letter from David P. Wheatland to Stephen T. Riley regarding permanent loan of the pantorgraph dated March 16, 1962 (in instrument file); original and photocopied hand written letter from David P. Wheatland to Stephen T. Riley regarding the pantograph dated June 23 1961 (in instrument file)
Object number: 1998-1-1617
Gottfried G. Ledder
Date: circa 1904
Accessories: triangular mahogany case
Object number: 1997-1-1857
W. & S. Jones
Date: circa 1820
Accessories: wooden storage case
ivory caps
extra brass arm
Object number: DW0807
Keuffel & Esser Company
Date: circa 1875
Accessories: pantograph weight (5140b); wooden stands
Object number: 5140a
Peter Hill
Date: circa 1820
Accessories: storage box
two original curatorial information cards
Object number: DW0162
John Bleuler
Date: circa 1790
Accessories: wooden storage case
three ivory tiles fallen off the instrument
two original curatorial cards
Object number: DW0454
American
Date: late 19th century - early 20th century
Object number: 1997-1-1853