Squares & Triangles -- T-Squares

• 

  Japanese L-Square

  Description

  In 1876 the Japanese Empire Department of Education exhibited many instruments at the Centennial International Exhibition, a World’s Fair held in Philadelphia. After the exhibition, John Eaton, the U.S. Commissioner of Education, arranged for the transfer of Japan's entire exhibit—including this object—to the Bureau of Education (then part of the Department of the Interior) for a planned museum. The museum closed in 1906, and much of the collection was transferred to the Smithsonian in 1910.

  On one side, this 18-1/2" L-shaped brass instrument is divided along the outside of its short leg into 7.5 units of 1-3/16" (3 cm). Each unit is thus roughly equivalent to the sun, a traditional Japanese unit of length that is 1/10 of a shaku, a "foot" measure. The units are subdivided into 10 parts. The fifth unit is marked with an arrangement of five dots.

  The outer edge of the long leg is divided into ten units of 1-3/4" (4.3 cm). Each unit is subdivided into tenths. From the right, the fifth and tenth units are marked with an arrangement of five dots. The other units are marked with single dots. A single dot also marks the 0.9 points. Groups of three dots mark the 3.55 and 7.05 points, and another group of three dots marks a point to the left of the divisions on the scale.

  The inner edge of the long leg is divided from left to right into five units of 1-13/16" (4.5 cm) and five sun. The larger units are marked with Japanese characters. The sun are subdivided into tenths and marked with single dots, except for the fifth unit, which is marked with five dots.

  On the other side, the outer edges of both legs are divided into sun subdivided into tenths. The midpoint of each unit is marked with three dots. The fifth, tenth, and fifteenth units from the vertex are marked with five dots. The instrument was designed for measuring lengths, drawing right angles, and determining whether two lines are perpendicular to one another.

  Other educational mathematical objects exhibited by Japan in 1876 include MA.261283, MA.261284, MA.261285, MA.261286, MA.261287, MA.261289, MA.261291, MA.261292, MA.261293, MA.261294, MA.261298, MA.261299, MA.261301, MA.261302, MA.261305, MA.261306, and MA.261313.

  References: Japan. Department of Education, An Outline History of Japanese Education: Prepared for the Philadelphia International Exhibition, 1876 (New York: D. Appleton, 1876), 121–122, 191–202; U.S. Centennial Commission, International Exhibition, 1876. Reports and Awards, ed. Francis A. Walker (Washington, D.C.: Government Printing Office, 1880), viii:143, 335; U.S. Bureau of Education, Annual Report of the Commissioner (1876), ccxi–ccxii.

  Location

  Currently not on view

  date made

  before 1876

  ID Number

  MA.261295

  accession number

  51116

  catalog number

  261295

  Data Source

  National Museum of American History

• 

  Japanese L-Square and Calipers

  Description

  This 6-1/2" brass T-square is composed of two L-shaped brass pieces. The bottom piece slides along a groove in the long leg of the top piece. The outer edges on one side and the inner edges of the other side of all four legs are divided into units of 1-3/16" (3 cm). Each unit is thus roughly equivalent to the sun, a traditional Japanese unit of length that is 1/10 of a shaku, a "foot" measure. The units are subdivided into 50 parts. Whole and half-units are marked with zeroes.

  The instrument was designed for measuring lengths, drawing right angles, and determining whether two lines are perpendicular to one another. When the two pieces are pulled apart, the instrument also functions as a caliper, to measure the width of a small object or the dimensions of part of a finished drawing. The English workshop of George Adams Jr. made a similar instrument from wood and brass in the late 18th century. Compare also to MA.261304 and to caliper rules such as MA.261299 and 1990.0099.01.

  In 1876 the Japanese Empire Department of Education exhibited many instruments at the Centennial International Exhibition, a World’s Fair held in Philadelphia. After the exhibition, John Eaton, the U.S. Commissioner of Education, arranged for the transfer of Japan's entire exhibit to the Bureau of Education (then part of the Department of the Interior) for a planned museum. The museum closed in 1906, and much of the collection, including this object, was transferred to the Smithsonian in 1910.

  References: William Ford Stanley, Mathematical Drawing and Measuring Instruments, 6th ed. (London: E. & F. N. Spon, 1888), 32–33; Howard Dawes, Instruments of the Imagination: A History of Drawing Instruments in Britain, 1600–1850 (The Dawes Trust Ltd., 2009), 80; "Caliper Rules," in A Source Book for Rule Collectors, ed. Philip E. Stanley (Mendham, N.J.: Astragal Press, 2003), 178–180; Japan. Department of Education, An Outline History of Japanese Education: Prepared for the Philadelphia International Exhibition, 1876 (New York: D. Appleton, 1876), 121–122, 191–202; U.S. Centennial Commission, International Exhibition, 1876. Reports and Awards, ed. Francis A. Walker (Washington, D.C.: Government Printing Office, 1880), viii:143, 335; U.S. Bureau of Education, Annual Report of the Commissioner (1876), ccxi–ccxii.

  Location

  Currently not on view

  date made

  before 1876

  ID Number

  MA.261296

  accession number

  51116

  catalog number

  261296

  Data Source

  National Museum of American History

• 

  Japanese L-Square with Calipers

  Description

  This 8" brass T-square is shaped like an L and has a second short leg attached to a slide on the long leg. On one side, the outer edge of the square is divided into units of 1-3/16" (3 cm), roughly equivalent to the sun, a traditional Japanese unit of length. Each unit is subdivided into 20 parts. The units on the long leg are marked with an O, with three circles marking the fifth unit. The inner edge of the long leg has a 15-centimeter scale, divided to millimeters. The back of the square has a diagonal scale. Compare to MA.261296.

  In 1876 the Japanese Empire Department of Education exhibited many instruments at the Centennial International Exhibition, a World’s Fair held in Philadelphia. After the exhibition, John Eaton, the U.S. Commissioner of Education, arranged for the transfer of Japan's entire exhibit to the Bureau of Education (then part of the Department of the Interior) for a planned museum. The museum closed in 1906, and much of the collection, including this object, was transferred to the Smithsonian in 1910.

  References: Japan. Department of Education, An Outline History of Japanese Education: Prepared for the Philadelphia International Exhibition, 1876 (New York: D. Appleton, 1876), 121–122, 191–202; U.S. Centennial Commission, International Exhibition, 1876. Reports and Awards, ed. Francis A. Walker (Washington, D.C.: Government Printing Office, 1880), viii:143, 335; U.S. Bureau of Education, Annual Report of the Commissioner (1876), ccxi–ccxii.

  Location

  Currently not on view

  date made

  before 1876

  ID Number

  MA.261304

  accession number

  51116

  catalog number

  261304

  Data Source

  National Museum of American History

• 

  T-Square

  Description

  A wooden bar (6-1/8" x 2" x 3/4") is attached to a flat wooden handle (17-7/8" x 2" x 1/8") by nine wooden pegs. By the 17th century, draftsmen used T-squares to help them draw horizontal lines. The instrument was also used in conjunction with a set square or triangle to draw vertical and diagonal lines. The dating of other objects from this donor suggests this object was made about 1900. Compare to MA.328397 and MA.328398.

  Reference: Maya Hambly, Drawing Instruments, 1580–1980 (London: Sotheby's Publications, 1988), 113.

  Location

  Currently not on view

  date made

  ca 1900

  ID Number

  MA.328396

  accession number

  272517

  catalog number

  328396

  Data Source

  National Museum of American History

• 

  T-Square

  Description

  This 19" wooden T-square has a curved top piece attached to the handle by two steel screws. The back of the top piece has a ridge for positioning against a table. A hole at the end of the handle is for hanging the instrument. It has no markings. The dating of other objects from this donor suggests this object was made about 1900. Compare to MA.328396 and MA.328398.

  Location

  Currently not on view

  date made

  ca 1900

  ID Number

  MA.328397

  accession number

  272517

  catalog number

  328397

  Data Source

  National Museum of American History

• 

  T-Square

  Description

  This 51-1/2" wooden T-square has a scalloped top piece attached to the handle by 6 brass screws. A hole at the end of the handle is for hanging the instrument. It has no markings, but paint and ink stains on the handle indicate it was heavily used. The dating of other objects from this donor suggests this instrument was made about 1900. Compare to MA.328396 and MA.328397.

  Location

  Currently not on view

  date made

  ca 1900

  ID Number

  MA.328398

  accession number

  272517

  catalog number

  328398

  Data Source

  National Museum of American History

• 

  Brown & Sharpe 510 Draftsman's Protractor

  Description

  See also ID number 1977.0460.01. After the inventor of this draftsman's protractor, Alton J. Shaw, left Darling, Brown & Sharpe of Providence, R.I., Samuel Darling patented a vernier scale that was a fraction of the size of a standard vernier scale. Darling then claimed to apply his vernier to the draftsman's protractor, replacing the original patent date in the maker's mark with the December 2, 1890, date of this patent. See, for example, the illustration in Brown & Sharpe's 1899 Catalogue No. 101 and Price Lists. This vernier read to only five minutes of accuracy, while Shaw's earlier vernier read to one minute of accuracy. Darling argued, however, that the coarser scale was easier to read and sufficed for most situations that arose in engineering drawing.

  In any event, the draftsman's protractor continued to sell steadily into the 20th century. Advertisements extolled the instrument's versatility, including its ability to function as a drawing triangle and as an extension of a T-square. The original patent date reappeared on the instrument in 1902 and 1904 but disappeared again by 1916, by which time Brown & Sharpe also changed the protractor's catalog number from 530 to 510. Other dealers, including Keuffel & Esser, W. & L. E. Gurley, and L. S. Starrett, also sold the draftsmen's protractor.

  The chief difference between this example of the instrument and ID number 1977.0460.01 is the reduced precision of the vernier, which is even marked: FIVE MINUTES. This protractor has 40 unmarked divisions, instead of 30. The signature is: 510; BROWN & SHARPE MFG. CO. (/) PROVIDENCE. R.I. U.S.A. The handle also bears the Brown & Sharpe logo of two rectangles at right angles to one another, with the letters B∙S above the horizontal rectangle and the words TRADE MARK below the horizontal rectangle. Of surviving 20th-century Brown & Sharpe catalogs, this protractor most closely resembles the illustration printed in 1925. The extending arm of the protractor is rusting.

  The protractor is stored in a blue paper box covered with the company logo and the words BROWN & SHARPE. A label on one end of the lid reads: 510; ORDER BY NUMBER 599-510 (/) BROWN & SHARPE DRAFTSMEN'S PROTRACTOR (/) MADE IN U.S.A. A label on the other end of the lid reads: POST (/) 0585 (/) THE FREDERICK POST CO. CHICAGO. Post retailed scientific and drawing instruments in the 20th century. An undated sheet with tables of angles for dividing circles and for tapers per foot is in the box.

  References: Samuel Darling, "Vernier-Scale" (U.S. Patent 442,020 issued December 2, 1890); Kenneth L. Cope, intro., A Brown & Sharpe Catalogue Collection, 1868 to 1899 (Mendham, N.J.: The Astragal Press, 1997); Brown & Sharpe Mfg. Co., Catalogue (Providence, R.I., 1902), 372; Brown & Sharpe Mfg. Co., Catalogue No. 138 (Providence, R.I., 1925), 504–505.

  Location

  Currently not on view

  date made

  ca 1925

  maker

  Brown & Sharpe Manufacturing Company

  ID Number

  1990.0317.02

  accession number

  1990.0317

  catalog number

  1990.0317.02

  Data Source

  National Museum of American History

• 

  Dietzgen 12066-24 T-Square and 4410-2 1/2 Drawing Board

  Description

  The 18" X 24" drawing board is made of six strips of pine, joined with tongue and groove construction to two pine endpieces. The board is pieced to allow for expansion and contraction. It is not marked. Between 1926 and 1938, the Eugene Dietzgen Company added this size of board to its model 4410 line of drawing boards.

  The 26-3/8" ash T-square is lined with maple on the handle. The head is 13" wide and painted black. The handle is marked: DIETZGEN (/) GLOBE (/) 12066-24. A drawing of the Earth appears around the word "GLOBE." A round hole at the end of the handle permits hanging. Between 1926 and 1938, Dietzgen began offering a "school quality" version of its model 2066 line of T-squares and gave that version the model number 12066.

  George Norton (1927–2009) purchased these tools in 1944 as part of a "practical drawing outfit" (model number 1100BW) that also included two celluloid triangles, a triangular scale, a celluloid protractor, a celluloid French curve, a box of thumb tacks, two pencils, one eraser, one art gum, one pencil pointer, twelve sheets of sandpaper, one bottle of black ink, six sheets of drawing paper, one instruction book, and a lettering chart. He paid $4.60 for the entire boxed kit. He used the instruments as a toolmaker for the U.S. Naval Gun Factory in Washington, D.C. He worked for the Smithsonian from the early 1960s until 1989.

  References: Catalog of Eugene Dietzgen Co., 12th ed. (Chicago, 1926), 217, 291; Catalog of Eugene Dietzgen Co., 15th ed. (Chicago, 1938), 203, 303, 390; "George A. Norton Jr., Museum Specialist," Washington Post, January 1, 2010, http://www.washingtonpost.com/wp-dyn/content/article/2010/01/01/AR2010010101675.html; accession file.

  Location

  Currently not on view

  date made

  1944

  maker

  Eugene Dietzgen Company

  ID Number

  1997.0105.01

  catalog number

  1997.0105.01

  accession number

  1997.0105

  Data Source

  National Museum of American History

• 

  Sterling Plastics 542 T-Square

  Description

  This 13" white plastic T-square is marked on the handle: STERLING – 542. It is also marked: MADE USA. The handle has a scale of 12 inches, divided to 1/16" and numbered by ones from 1 to 12, and a 30.5 centimeter scale, divided to millimeters, numbered by ones from 1 to 30, and marked: MM. A hole near the end of the handle permits hanging.

  George and Mary Staab operated Sterling Plastics in Mountainside, New Jersey, from 1938 through the late 1960s. The firm was a division of Borden Chemical Company in the 1970s and 1980s and was purchased by Sanford Corporation in 1988. See also MA.335327, 1988.0807.01, 1990.0689.01, and 1998.3104.01. Isaac Giacinto Molella, who worked as an electrical engineer for General Electric in the United States, North Africa, and Europe in the 1950s, previously owned this T-square.

  Location

  Currently not on view

  date made

  1950s

  maker

  Sterling Plastics

  ID Number

  1992.0433.02

  accession number

  1992.0433

  catalog number

  1992.0433.02

  Data Source

  National Museum of American History

• 

  Fairgate 155-T T-Square

  Description

  This 27" aluminum and plastic T-square has scales of inches along both sides of the handle. One scale is divided to 1/8" and the other is divided to 1/16". Both scales are numbered by ones from 1 to 24. The end of the handle has a hole for hanging. The handle is marked: FAIRGATE 115–T. It is also marked: COLD SPRING, N.Y. 10516 MADE IN U.S.A.

  The blue plastic crosspiece has holes in its interior. The lower edge of the crosspiece is marked with a scale of units slightly longer than one inch, divided to eighths and numbered by ones from 1 to 5 on both sides of the handle. The back of the crosspiece is marked: FAIRGATE (/) COLD SPRING NY (/) MADE IN U.S.A.

  This instrument was found in the collections in 1984. The Fairgate Rule Company began manufacturing high-quality aluminum scale rules, T-squares, L-squares, templates, and curves in Cold Spring, N.Y., in 1946 and remains in business as of 2013. This particular T-square is now sold as model number 63-124 for $14.10.

  Reference: Fairgate Rule Company, "Frequently Asked Questions," https://fairgate.com/Frequently-Asked-Questions_ep_42-1.html.

  Location

  Currently not on view

  date made

  1946-1984

  maker

  Fairgate Rule Company Inc..

  ID Number

  1990.0316.06

  accession number

  1990.0316

  catalog number

  1990.0316.06

  Data Source

  National Museum of American History

Pages