Science & Mathematics

The Museum's collections hold thousands of objects related to chemistry, biology, physics, astronomy, and other sciences. Instruments range from early American telescopes to lasers. Rare glassware and other artifacts from the laboratory of Joseph Priestley, the discoverer of oxygen, are among the scientific treasures here. A Gilbert chemistry set of about 1937 and other objects testify to the pleasures of amateur science. Artifacts also help illuminate the social and political history of biology and the roles of women and minorities in science.

The mathematics collection holds artifacts from slide rules and flash cards to code-breaking equipment. More than 1,000 models demonstrate some of the problems and principles of mathematics, and 80 abstract paintings by illustrator and cartoonist Crockett Johnson show his visual interpretations of mathematical theorems.

This one-sided, five-inch white molded plastic rule has a plastic indicator with a hairline and plastic edges. A, D, and K scales are on the base, with B, CI, and C scales on one side of the slide and S, L, and T scales on the other side of the slide.
Description
This one-sided, five-inch white molded plastic rule has a plastic indicator with a hairline and plastic edges. A, D, and K scales are on the base, with B, CI, and C scales on one side of the slide and S, L, and T scales on the other side of the slide. The top and bottom edges are beveled, with a scale of 5 inches divided to 32nds of an inch on the top and a scale of 12.5 centimeters divided to millimeters on the bottom. The top of the base is marked (in red): No. 1771 REDIRULE ® DIETZGEN MADE IN U.S.A. Three screws for adjusting the rule are on the back of the instrument. The rule fits in a brown leather sheath marked: DIETZGEN. The sheath fits in an orange paper box marked on each end: DIETZGEN Redi-Rule ® (/) 5 INCH POCKET SLIDE RULE (/) Molded Plastic, Leather Sheath 1771. The rule was received with an instruction manual, 1993.0357.02.01.
According to records of the U.S. Patent and Trademark Office, Eugene Dietzgen Company began using the phrase REDIRULE to describe slide rules in 1944, applied for a trademark on the term in 1947, and received the trademark in 1953. According to Peter Hopp and Bruce Babcock, Dietzgen manufactured model 1771 of the Redirule or Redi-rule from 1941 to 1972. (Another Redirule, model 1776, had an additional six scales and metal endpieces.) Dietzgen's catalog for 1948–1949 describes model 1771 as "a real pocket companion" that "weighs no more than your pen."
References: Peter M. Hopp, Slide Rules: Their History, Models, and Makers (Mendham, N.J.: Astragal Press, 1999), 160; Bruce Babcock, "Dietzgen Catalog Matrix," Journal of the Oughtred Society 5, no. 2 (1996), http://sliderulemuseum.com/Manuals/Dietzgen_CatalogMatrix_BruceBabcock1996_chart.jpg; Dietzgen Redirule Instruction Manual (Chicago: Eugene Dietzgen Co., n.d.), http://sliderulemuseum.com/Manuals/M12_Dietzgen_1776_redirule_ref-P023.jpg; Ovid W. Eshbach and H. Loren Thompson, Self-teaching Instruction Manual: Dietzgen Decimal Trig Type Log Log Slide Rule (Chicago: Eugene Dietzgen Co., 1960), 107–108; http://sliderulemuseum.com/Manuals/Dietzgen_1734_Manual.pdf.
Location
Currently not on view
date made
1953-1972
maker
Eugene Dietzgen Company
ID Number
1993.0357.02
accession number
1993.0357
catalog number
1993.0357.02
This eight-wheeled stylus-operated non-printing adding machine has plastic wheels and a metal frame. The first wheel is red and has eight holes near its edge for adding fractions. The second wheel from the left is white and has 12 holes near its edge for adding inches.
Description
This eight-wheeled stylus-operated non-printing adding machine has plastic wheels and a metal frame. The first wheel is red and has eight holes near its edge for adding fractions. The second wheel from the left is white and has 12 holes near its edge for adding inches. The remaining six wheels each have ten holes around the edge. The rightmost is red, the next three are white, and the next two are red. All the wheels are labeled around the outside with digits for use in addition, and around the inside with digits for use in subtraction. A steel stylus and a clearing bar fit into the right side.
The top edge of the instrument has an 11-inch scale of equal parts, divided to sixteenths of an inch. A sales receipt indicates the machine was purchased September 19, 1951, by Frederick Mathesius for $12.95. A second sheet gives operating instructions. The machine is stored in a tan and purple cardboard box. It was made by Reliable Typewriter & Adding Machine Company of Chicago, Illinois.
References:
Typewriter Topics, vol. 66, August, 1927, pp. 36-37 (announced as coming in September - $10.00), Typewriter Topics, vol. 72, June, 1929, p. 29 (cost $15.00); Office Appliances, vol. 87, January, 1948, p. 138, 182 (price $12.95); Office Appliances, vol. 98, Oct., 1953, p. 233 (price $14.95).
Location
Currently not on view
date made
1951
distributor
H. & M. Button Company
maker
Reliable Typewriter & Adding Machine Corporation
ID Number
1996.0220.01
catalog number
1996.0220.01
accession number
1996.0220
By the 1960s, when this test was published, employers often gave job candidates standardized examinations. This set of one arithmetic and one reading test was designed particularly for adults with limited basic skills in these areas.
Description
By the 1960s, when this test was published, employers often gave job candidates standardized examinations. This set of one arithmetic and one reading test was designed particularly for adults with limited basic skills in these areas. According to the test booklets, they were developed by Science Research Associates (SRA), a subsidy of IBM.
This collection contains the Science Research Associates (SRA) Arithmetic Index, the SRA Reading Index, and the Reading and Arithmetic Indexes Preliminary Manual. The SRA Arithmetic Index contains fifty-four questions related to: addition and subtraction of whole numbers, multiplication and division of whole numbers, fractions, and decimals and percentages. The SRA Reading Index contains sixty questions related to: picture-word association, word decoding, phrase comprehension, sentence comprehension, and paragraph comprehension. Both tests contain the original carbon paper. The manual describes the main audience of the tests as being “adults and youths over 14” and “for use with applicants for entry-level jobs and special training programs, where the basic skills of the applicants are often too low to be reliably evaluated by typical selection tests.” The manual is a ten-page long booklet that includes: features of the Reading-Arithmetic Indexes, development and descriptive statistics, administering the tests, score, and interpretation and use.
Location
Currently not on view
date made
1968
publisher
Science Research Associates, Inc
ID Number
1986.3133.07
catalog number
1986.3133.07
nonaccession number
1986.3133
This full-keyboard non-printing adding machine is a relatively late example of the products of Felt & Tarrant Manufacturing Company of Chicago.
Description
This full-keyboard non-printing adding machine is a relatively late example of the products of Felt & Tarrant Manufacturing Company of Chicago. It has a gray-green metal case, a metal mechanism, and plastic keys.
The ten columns of color-coded green and white octagonal plastic keys have nine keys in each column. Complementary digits are indicated and the keys are alternately concave (odd digits) and flat (even digits). The key stems are flat and have no springs around them. The case slopes up toward the back, so that the amount of key stem that protrudes is the same for all digits. A row of subtraction buttons is below the number keys and a row of decimal markers is in front of it. Digits in the running total appear in a set of 11 windows in front of the keys. Digits in the total under columns of white keys are black, while result digits under columns of green keys are red. A red correction key to the right of the keyboard that releases the keyboard after a partial keystroke error has been corrected. A a metal zeroing lever also is right of the keyboard.
The serial number, stamped on the keyboard on the right at the front, is: W.M. (/) 446522. The front and back sides are marked: COMPTOMETER. Several dates are marked on the bottom of the machine with various initials. They include 8/17/45 and12-12-50. A metal plate attached to the bottom of the machine lists 33 patent numbers. Behind the keyboard is the mark: FELT & TARRANT MANUFACTURING CO. CHICAGO, USA.
The model M Comptometer was introduced in October of 1939, starting with serial number 400,001. By March 1947 some 64,500 of these machines had sold. The WM was a “War Model,” adjusted to conserve materials.
This example is from the collection of calculating machines assembled by Myron R. Smith.
Location
Currently not on view
date made
ca 1945
maker
Felt & Tarrant Manufacturing Company
ID Number
1989.0325.04
maker number
W.M. 446522
catalog number
1989.0325.04
accession number
1989.0325
This clear plastic sixth-circle protractor is divided along its outer edge by hundredths and marked by tenths from +1.7 to +0.1 (in black print) and from -0.1 to -3.4 (in red print). The scale is labeled: TIME INTERVAL, SECONDS.
Description
This clear plastic sixth-circle protractor is divided along its outer edge by hundredths and marked by tenths from +1.7 to +0.1 (in black print) and from -0.1 to -3.4 (in red print). The scale is labeled: TIME INTERVAL, SECONDS. The left edge of the protractor is divided by tens and marked by hundreds from 2000 to 600. The scale is labeled: LENGTH OF SUB-BASE, YARDS. The right edge of the protractor is divided by halves and marked by ones from 14 to 1. The scale is labeled: THOUSANDS OF YARDS (/) 1/25000.
The interior of the protractor is filled with diagonal lines. Three scales are among the diagonal lines, each numbered by tenths in black and in red print. The outermost is numbered from 3.9 to 0.1; the middle scale is numbered from 3.0 to 0.1; and the innermost is numbered from 2.2 to 0.1.
The maker's mark is near the vertex, which is notched: 2 SOUND SECONDS (/) TEMPLATE, 1/25000 (/) FELSENTHAL INSTRUMENTS CO. (/) MFR'S PART NO. FAE-19B (/) MFR'S CODE 22040. There is a large plus sign to the right of the maker's mark.
The Chicago firm that manufactured this protractor was known as Felsenthal Instrument Co. in the 1960s and 1970s. Ben Wharton Rau (1904–1995) and his wife, Margery Felsenthal Rau (1916–2010), arranged the donation of this object and many other instruments to the Smithsonian. Margery's father, Irving (1887–1956), was one of the "Sons" of G. Felsenthal & Sons, as the company was known in the 1940s and 1950s. Margery's grandfather, Gabe Felsenthal, founded the firm in 1899.
Ben Rau worked for the Felsenthals. His duties included touring military facilities with a large display of the company's products. He catalogued hundreds of instruments when the company went out of business in 1976. He dated this protractor and 1977.1141.01 to 1950. While the form was indeed probably older, the maker's name on the instrument indicates it was manufactured in the 1960s or 1970s. Rau also held patents on a collapsible film reel, a proportional divider, and a belt buckle assembly.
See also 1977.1141.01, 1977.1141.03, 1977.1141.05, 1977.1141.08, 1977.1141.09, 1977.1141.10, 1977.1141.11, 1977.1141.12, 1977.1141.18, 1977.1141.19, 1977.1141.20, 1977.1141.21, 1977.1141.22, 1977.1141.23, 1977.1141.24, 1977.1141.30, and 1977.1141.39.
References: Deborah J. Warner, “Browse by Maker: Felsenthal,” National Museum of American History Physical Sciences Collection: Navigation, http://amhistory.si.edu/navigation/maker.cfm?makerid=173; "Irving G. Felsenthal," Chicago Tribune, February 26, 1956, http://www.susaneking.com/genealogy/showsource.php?sourceID=S01752&tree=GreenebaumSam; Copyright Office, Library of Congress, "Books and Pamphlets," Catalog of Copyright Entries, 3rd ser., 16, part 1, no. 2 (1964): 1392; Ben W. Rau, "Collapsible Film Reel" (U.S. Patent 3,447,759 issued June 3, 1969), "Proportional Divider" (U.S. Patent D214,399 issued June 10, 1969), "Belt Buckle Assembly" (U.S. Patent 3,475,797 issued November 4, 1969).
Location
Currently not on view
date attributed by donor
1950
date made
1970s
maker
Felsenthal Instrument Co.
ID Number
1977.1141.02
accession number
1977.1141
catalog number
336386
This clear plastic semicircular protractor is divided by tens and marked by hundreds from 100 to 3,100 mils and from 3,300 to 6,300 mils. Mils are units used in artillery and other military applications; 1,000 mils is equivalent to 56.25°. A pinhole is at the origin point.
Description
This clear plastic semicircular protractor is divided by tens and marked by hundreds from 100 to 3,100 mils and from 3,300 to 6,300 mils. Mils are units used in artillery and other military applications; 1,000 mils is equivalent to 56.25°. A pinhole is at the origin point. The bottom edge of the protractor is divided by hundreds and marked by thousands of meters from 6,000 to 0. A vernier appears to the right of the scale. The scale is labeled: 1/25,000. Superimposed on the scale is a second scale, divided by two hundreds and marked (in red) by two thousands from 0 to 12,000. A vernier appears to the left of that scale, which is labeled (in red): 1/50,000.
The interior of the protractor has a semicircular opening with a groove parallel to the origin point. Below the opening is a maker's mark: FSN 6675-556-0118 (/) PROTRACTOR, 16 INCH (/) FELSENTHAL INSTRUMENTS CO. (/) CHICAGO (/) FAE-22A. The letters U.S. are printed above the origin point. Donor Ben Rau, who worked for Felsenthal, dated the object to 1950, but the form of the signature indicates the protractor was probably manufactured for the U.S. Army in the 1960s.
This protractor is very similar to 1977.1141.12. See also 1977.1141.01, 1977.1141.02, 1977.1141.03, 1977.1141.05, 1977.1141.08, 1977.1141.09, 1977.1141.10, 1977.1141.11, 1977.1141.18, 1977.1141.19, 1977.1141.21, 1977.1141.22, 1977.1141.23, 1977.1141.24, 1977.1141.30, and 1977.1141.39.
Reference: Copyright Office, Library of Congress, "Books and Pamphlets," Catalog of Copyright Entries, 3rd ser., 16, part 1, no. 2 (1964): 1392.
Location
Currently not on view
date attributed by donor
1950
date made
1960s
maker
Felsenthal Instrument Co.
ID Number
1977.1141.20
accession number
1977.1141
catalog number
336404
This device assists in calculations of changes in the range of a gun because of meteorological conditions, particularly wind speed and temperature. A rotating disc and pointer attached to the plastic base have the scales required to correct for wind speed.
Description
This device assists in calculations of changes in the range of a gun because of meteorological conditions, particularly wind speed and temperature. A rotating disc and pointer attached to the plastic base have the scales required to correct for wind speed. A scale toward the bottom of the base gives the temperature correction. Both of these corrections are in percentages of the range. Summing them gives the total meteorological correction as a percentage of the range. One then can use a range correction chart to find the actual range correction.
A mark on the front of the instrument reads: Signal Corps U. S. Army (/) SOUND VELOCITY CORRECTOR PT-62/TSS-1 (/) Order No. 3531-CEGSA-45 G. FELSENTHAL & SONS - CHICAGO.
The instrument was designed and made for the United States Army by G. Felsenthal & Sons of Chicago in 1945. It had Felsenthal designation FAS-2.
For a related range correction chart, see 1977.1141.43.
Reference:
Accession file.
Location
Currently not on view
date made
1945
maker
G. Felsenthal & Sons, Inc.
ID Number
1977.1141.42
catalog number
336426
accession number
1977.1141
This plastic green and white slide rule carries out calculations related to the capacity, draft, and resistance of cargo tankers able to carry up to 26,700 deadweight metric tons of petroleum or petroleum products. Eight metal rivets hold the rule together.
Description
This plastic green and white slide rule carries out calculations related to the capacity, draft, and resistance of cargo tankers able to carry up to 26,700 deadweight metric tons of petroleum or petroleum products. Eight metal rivets hold the rule together. The front is marked: KOEHLER TRIM-NUMERAL CALCULATOR (/) 26700 D.W.T. TANKERS. The bottom of the front of the slide is marked: MARKETED BY JEFKO PRODUCTS COMPANY, 100 OAKLAND ROAD, MAPLEWOOD, NEW JERSEY. The back of the rule and the back of the slide are both marked: COPYRIGHT 1954 BY J. F. KOEHLER.
According to the accession file, this instrument was made by Felsenthal Instrument Company in 1954 as model number FDJ-23. For company history, see 1977.1141.01 and 1977.1141.02. The address for JEFKO Products is a single-family home constructed in 1925. A New Jersey engineer named J. Franklin Koehler (b. 1927) earned a B.S. in naval architecture and marine transportation from the Massachusetts Institute of Technology in 1951 with a thesis titled "Influence of Rising Operating Costs on Relative Economic Operation of Higher Speed Cargo Vessels."
Location
Currently not on view
date made
1954
maker
Felsenthal Instrument Co.
ID Number
1977.1141.38
catalog number
336422
accession number
1977.1141
This ten-inch aluminum linear slide rule is coated with yellow plastic and has a flat nylon indicator. The back of the base has LL1, LL2, A, D, LL3, and LL4 scales, with B, T, ST, S, K, and C scales on the slide. The left end of the slide is marked: MODEL 14 (/) U.S.
Description
This ten-inch aluminum linear slide rule is coated with yellow plastic and has a flat nylon indicator. The back of the base has LL1, LL2, A, D, LL3, and LL4 scales, with B, T, ST, S, K, and C scales on the slide. The left end of the slide is marked: MODEL 14 (/) U.S. The right end has the Pickett triangular logo used between 1958 and 1962. The style of the grooved stamped aluminum posts is also consisted with this timeframe.
The top front of the base has scales for "opposite angle" (sine) in both degrees and mils; the top bottom of the base has "Distance D" and A scales. The front of the slide has scales for apex angle (in both mils and degrees), tangent, sine-tangent, sine, and base. The top center of the base is marked: U.S. MILITARY SLIDE RULE.
Pickett & Eckel, Inc., of Chicago and Alhambra, Calif., made this instrument for computations related to the use of field artillery. It fits in an orange-red leather case that has the Pickett logo and US stamped in gold on the front and a metal loop on the back for suspension from a belt. The case is lined with white plastic. A white plastic "data strip" slides into a slot on the case. The strip contains diagrams and equations for trigonometric functions, traverse computations, azimuth and distance from coordinates, triangle computation, and the distance to an artillery target.
The case fits in a brown, black, white, and yellow paper box. The box and its insert are repeatedly marked: ALL METAL SLIDE RULE a rule for every need. The Pickett logo appears between the two segments of the mark. The end of the box once bore a paper tag: 1 UNIT - FSN - 7520 - 656 - 0660 (/) Slide Rule – Military, Field Artillery (/) With Data Strip and Case MIL-S-20195B (/) Mfg. Contr.; PICKETT & ECKEL, INC. Model No. 14.
The object comes from the Felsenthal Collection of computing devices. (See Felsenthal's company history with 1977.1141.02.) Donor Ben Rau suggested a date of 1965 for this slide rule, but it was probably made a few years earlier. Compare to the box collected with 1995.0126.02.
References: Accession File; Tom Bullock, "Pickett 14 U.S. military slide rule," December 8, 2009, http://www.tbullock.com/sliderule.html; Clark McCoy, "Highlights of the A. J. Boardman Collection of Pickett Slide Rules," Journal of the Oughtred Society 16, no. 2 (2007): 10–14.
Location
Currently not on view
date made
1958-1962
maker
Pickett & Eckel, Incorporated
ID Number
1977.1141.29
catalog number
336413
accession number
1977.1141
This 32-page booklet was received with 1979.0601.02. Its citation information is: Maurice L. Hartung, How to Use the Deci Log Log Slide Rule (Chicago: Pickett & Eckel, Inc., 1947).
Description
This 32-page booklet was received with 1979.0601.02. Its citation information is: Maurice L. Hartung, How to Use the Deci Log Log Slide Rule (Chicago: Pickett & Eckel, Inc., 1947). Hartung, a University of Chicago professor and consultant to Pickett & Eckel, provided a basic overview of mathematical operations on the slide rule. He then explained placing the decimal point; the inverted scales; scales for squares and cubes, logarithms, and trigonometry; and solving problems using multiple scales. He next described the log log scales in a section that has several diagrams of slide rules.
A pink paper sheet on caring for the slide rule is inside the booklet. A previous owner has written in a few corrections, including an updated population of the United States of 175 million in 1957.
Location
Currently not on view
date made
1947
author
Hartung, Maurice L.
ID Number
1979.0601.04
accession number
1979.0601
catalog number
1979.0601.04
This clear plastic semicircular protractor is divided by twenties and marked by two hundreds from 0 to 3,200 and from 3,200 to 6,400. A pinhole is at the origin point. The interior is labeled: ANGULAR MILS; 8016738. This protractor was item no. FAO-44.
Description
This clear plastic semicircular protractor is divided by twenties and marked by two hundreds from 0 to 3,200 and from 3,200 to 6,400. A pinhole is at the origin point. The interior is labeled: ANGULAR MILS; 8016738. This protractor was item no. FAO-44. Felsenthal Instruments Company manufactured it for the U.S. Army about 1958.
The Felsenthal Instruments Company was the leading supplier of mathematical instruments to the U.S. Army Air Force and the U.S. Navy Bureau of Aeronautics, particularly during World War II (when the firm was known as G. Felsenthal & Sons). After the company ceased operations in approximately 1976, it provided a large sample of its products to the Smithsonian.
See also 1977.1141.01, 1977.1141.02, 1977.1141.03, 1977.1141.05, 1977.1141.08, 1977.1141.09, 1977.1141.11, 1977.1141.12, 1977.1141.18, 1977.1141.19, 1977.1141.20, 1977.1141.21, 1977.1141.22, 1977.1141.23, 1977.1141.24, 1977.1141.30, and 1977.1141.39.
Location
Currently not on view
date made
ca 1958
maker
Felsenthal
ID Number
1977.1141.10
accession number
1977.1141
catalog number
336394
This 5-3/4" black plastic and chrome-plated mechanical pencil is marked near its top: CHICAGO Autopoint USA (/) PATD AND PATS PEND. The word "Autopoint" is in script. The end of the pencil above the mark uncaps to reveal an eraser.
Description
This 5-3/4" black plastic and chrome-plated mechanical pencil is marked near its top: CHICAGO Autopoint USA (/) PATD AND PATS PEND. The word "Autopoint" is in script. The end of the pencil above the mark uncaps to reveal an eraser. A metal clip allows the pencil to be secured in a shirt pocket. The pen is stored in a rectangular gray cardboard box marked: Pencil Used by H H sr. (c[h]rome plated).
Autopoint began manufacturing mechanical pencils in Chicago in 1918. Inventors assigned at least 30 patents to Autopoint between 1918 and 1929. One of the patents referred to on this pencil was taken out by Frank Deli of Chicago, for a metal pin that screwed into a threaded cylinder inside the pencil tip and thus acted to propel the lead. The diameter of the pin suggests the lead width was about 1 mm. The body of the pencil was to be made from bakelite or a similar plastic. Deli applied for his patent in 1921, although it was not granted until 1925. Bakelite, the plastics manufacturer, owned an interest in Autopoint from the 1920s to the 1940s. After several corporate acquisitions and reorganizations, Autopoint moved to Janesville, Wisc., in 1979, where it continues operations.
His daughter-in-law reported that Herman Hollerith Sr. owned this pencil. Hollerith (1860–1929) trained as a mining engineer. He joined the U.S. Census Office in 1879, where he pioneered the development of punch cards for tabulating machines. These machines dramatically sped up the processing of data in the 1890 census. In 1896 he founded the Tabulating Machine Company, which merged with three other companies in 1911 and became the International Business Machines Corporation (IBM) in 1924. Hollerith retired in 1921 and raised cattle on a farm in Maryland until his death, so he presumably acquired the pencil during his retirement. For depictions and examples of Hollerith machines, see 1977.0503.01, 1977.0503.02, and 2011.3121.01, MA.312896, MA.335634, MA.335635, and MA.333894. See also the NMAH object group on tabulating machines, http://americanhistory.si.edu/collections/object-groups/tabulating-equipment.
References: Autopoint, Inc., "About Us," http://autopointinc.com/about-us; Frank C. Deli, "Pencil" (U.S. Patent 1,552,123 issued September 1, 1925); Robert L. Bolin, "Web Resources Concerning the Mechanical Pencil Industry in Chicago," http://unllib.unl.edu/Bolin_resources/pencil_page/index.htm; William R. Aul, "Herman Hollerith: Data Processing Pioneer," Think, November 1972, http://www-03.ibm.com/ibm/history/exhibits/builders/builders_hollerith.html; United States Census Bureau, "Herman Hollerith," http://www.census.gov/history/www/census_then_now/notable_alumni/herman_hollerith.html.
Location
Currently not on view
date made
1921-1929
maker
Autopoint, Inc.
ID Number
1977.0503.03
catalog number
336122
accession number
1977.0503
While many protractors simply measure angles in degrees, others have been adapted for more specialized contexts. For instance, they may be combined with other drawing instruments, such as rulers or templates for flow chart components.
Description
While many protractors simply measure angles in degrees, others have been adapted for more specialized contexts. For instance, they may be combined with other drawing instruments, such as rulers or templates for flow chart components. Or, they may make measurements in other scales for angles, such as radians. Before computerized and satellite navigation equipment was in wide use, protractors were employed in military applications, including positioning artillery.
Thus, this clear plastic protractor, which is in the shape of a sixth-circle, permitted the user to plot the distance traveled by a projectile from the time that elapsed before the sound of the projectile was heard. The outer edge of the protractor's arc is divided by hundredths and marked by tenths from +3.4 to +0.1 (in black print) and from -0.1 to -3.4 (in red print). The scale is labeled: TIME INTERVAL, SECONDS and MIDPOINTS FOR 4-SECOND SUB-BASE, 1/25000.
A scale marked DEGREES is further inside the arc. It is divided by minutes and marked by fives from 55° to 0°. Finally, a scale for MILS is divided by tens and marked by hundreds from 1000 to 100. 1000 mils is equivalent to 56.25°. A scale for THOUSANDS OF YARDS 1/25000 is along the right edge of the protractor. It is divided by five-hundredths and marked by ones from 14 to 1.
The maker's mark is near the vertex: 4 SOUND SECONDS (/) FELSENTHAL INSTRUMENTS CO. (/) MFR'S PART NO. FAE-19A (/) MFR'S CODE 22040.
The Felsenthal Instruments Company was the leading supplier of mathematical instruments to the U.S. Army Air Force and the U.S. Navy Bureau of Aeronautics, particularly during World War II (when the firm was known as G. Felsenthal & Sons). After the company ceased operations in approximately 1976, it provided a large sample of its products to the Smithsonian.
See also 1977.1141.02, 1977.1141.03, 1977.1141.05, 1977.1141.08, 1977.1141.09, 1977.1141.10, 1977.1141.11, 1977.1141.12, 1977.1141.18, 1977.1141.19, 1977.1141.20, 1977.1141.21, 1977.1141.22, 1977.1141.23, 1977.1141.24, 1977.1141.30, and 1977.1141.39.
Reference: Deborah J. Warner, “Browse by Maker: Felsenthal,” National Museum of American History Physical Sciences Collection: Navigation, http://amhistory.si.edu/navigation/maker.cfm?makerid=173.
Location
Currently not on view
date attributed by donor
1950
date made
1970s
maker
Felsenthal Instrument Co.
ID Number
1977.1141.01
accession number
1977.1141
catalog number
336385
This clear plastic rectangular protractor is divided by single degrees and marked by tens from 10° to 170° and from 190° to 350°. Pinholes near the 20° and 60° marks allow for positioning the protractor.
Description
This clear plastic rectangular protractor is divided by single degrees and marked by tens from 10° to 170° and from 190° to 350°. Pinholes near the 20° and 60° marks allow for positioning the protractor. The bottom edge is divided by tenths of an inch and marked by ones from 1" to 5". The interior of the protractor contains three scales of equal parts: 1) divided by hundreds and marked by five hundreds from 0 to 2,500 yards, for a scale of 1/20,000; 2) divided by hundreds and marked by thousands from 0 to 7,000 yards, for a scale of 1/62,500; and 3) divided by hundreds and marked by five hundreds from 0 to 2,000 meters, for a scale of 1/20,000. There are verniers to the left of the first and third scales.
Near the top of the protractor is marked: U.S. 1957. The 1957 is believed to refer to the date of the object. The maker's mark is: G. FELSENTHAL & SONS, INC. (/) PART NO. FAE-9A.
This protractor is almost exactly like 1977.1141.08. See also 1977.1141.01, 1977.1141.02, 1977.1141.03, 1977.1141.05, 1977.1141.10, 1977.1141.11, 1977.1141.12, 1977.1141.18, 1977.1141.19, 1977.1141.20, 1977.1141.21, 1977.1141.22, 1977.1141.23, 1977.1141.24, 1977.1141.30, and 1977.1141.39.
Reference: Deborah J. Warner, “Browse by Maker: Felsenthal,” National Museum of American History Physical Sciences Collection: Navigation, http://americanhistory.si.edu/collections/navigation/maker.cfm?makerid=173.
Location
Currently not on view
date attributed by donor
1957
maker
G. Felsenthal & Sons, Inc.
ID Number
1977.1141.09
accession number
1977.1141
catalog number
336393
A pantograph is an instrument used to duplicate drawings, at different scales if need be. This example consists of four wooden arms held together with pins and a screw-eye with a wooden anchor support under one arm.
Description
A pantograph is an instrument used to duplicate drawings, at different scales if need be. This example consists of four wooden arms held together with pins and a screw-eye with a wooden anchor support under one arm. Two metal screw-eyes are placed in holes which are numbered from 1 to 10. There is a tracer point in one arm, but there no longer is a pencil point.
A mark stamped on one of the wooden bars reads: 1495 (/) POSTS. Below this is stamped an image of an eagle clutching a shield that is stamped P. This trademark appeared on the first page of the Frederick Post Company Catalog in 1903. By 1921, another trademark was used.
The pantograph is number 1495 in the catalog of The Frederick Post Company. The company was started by Frederick Post (1862-1936), a native of Hamburg who emigrated to the United States in 1885 and soon settled in Chicago. By the time of the 1900 U.S. Census, he was a manufacturer of artist's materials there. Post imported drawing instruments and slide rules as well as manufacturing them. Whether his firm made this pantograph is not known.
The instrument is from the estate of the American inventor of tabulating machines Herman Hollerith, Jr. In 1889, Hollerith introduced a device for punching cards for tabulating machines that was called a pantograph card punch. This pantograph dates from after that invention.
For information about the pantograph card punch, see MA.312896.
References:
U. S. Census 1900, 1910, 1920, 1930.
Catalogs of the Frederick Post Company.
Location
Currently not on view
date made
1903-1922
ID Number
1977.0114.04
accession number
1977.0114
catalog number
335636
This clear plastic circular protractor is divided by tenths and marked by ones from 1 to 63. In the 48-64 quadrant, it is also marked in red print by ones from 32 to 17. The scale is labeled: AZIMUTH-MILS (100). The interior of the 16–32 quadrant is cut out.
Description
This clear plastic circular protractor is divided by tenths and marked by ones from 1 to 63. In the 48-64 quadrant, it is also marked in red print by ones from 32 to 17. The scale is labeled: AZIMUTH-MILS (100). The interior of the 16–32 quadrant is cut out. Each of the straight sides bears a scale divided by fifties and marked by thousands from 0 to 4,000. The scales are labeled: METERS RF 1: 50,000.
An arm extending from the 0-16 quadrant is divided by tenths and marked by ones from 1 to 17. The scale is labeled: RANGE METERS (1000). The interior of the 32–48 quadrant bears a maker's mark: FELSENTHAL INSTRUMENTS CO. (/) MFR'S CODE 22040 (/) MFR'S PART NO. FAE-28. The protractor was used to predict the direction and distance of artillery rounds. Donor Ben Rau wrote "Massengale" (which may refer to a particular U.S. Army officer) on the tag he provided with this instrument, and he dated the object to 1966.
See also 1977.1141.01, 1977.1141.02, 1977.1141.03, 1977.1141.08, 1977.1141.09, 1977.1141.10, 1977.1141.11, 1977.1141.12, 1977.1141.18, 1977.1141.19, 1977.1141.20, 1977.1141.21, 1977.1141.22, 1977.1141.23, 1977.1141.24, 1977.1141.30, and 1977.1141.39.
Location
Currently not on view
date attributed by donor
1966
maker
Felsenthal Instrument Co.
ID Number
1977.1141.05
accession number
1977.1141
catalog number
336389
This chart, drawn on a rigid white plastic sheet, has five equally spaced concentric circles, each divided into eight equal sections by lines through the center of the circle.
Description
This chart, drawn on a rigid white plastic sheet, has five equally spaced concentric circles, each divided into eight equal sections by lines through the center of the circle. The outer circle is divided into 64 equal segments, which are numbered counterclockwise from 0 to 32 on the left half of the circle. On the right half, segments are numbered from 0 at the bottom counterclockwise to 30 at the top, and also from (34) to (64).
A mark at the bottom left reads: CARD, TANK RANGE (/) 8724207. A mark on the left top reads: HUNDREDS OF MILS. There are 6400 mils in a circle of 360 degrees angular measure.
The object comes from the Felsenthal Collection of computing devices. According to the accession file it was made by Felsenthal for the U.S. Army in 1955, and had Felsenthal designation FA0-51. It may have been used by the tank gunner to lay his gun on target, before the availability of electronic or laser sighting.
Reference:
Accession file 1977.1141.
Location
Currently not on view
date made
1955
maker
G. Felsenthal & Sons, Inc.
ID Number
1977.1141.06
catalog number
336390
accession number
1977.1141
This white plastic circular slide rule consists of a disc riveted to a square backing. The backing has a logarithmic scale of readings of a stadia rod used with a transit telescope, in feet. The disc has two logarithmic scales of angles.
Description
This white plastic circular slide rule consists of a disc riveted to a square backing. The backing has a logarithmic scale of readings of a stadia rod used with a transit telescope, in feet. The disc has two logarithmic scales of angles. The first scale gives the difference in elevation of the transit and the stadia rod, in feet. It represents multiplying the stadia reading by 1/2 sin 2A, where A is the vertical angle of the transit telescope. The second scale finds the horizontal distance of the rod in feet and represents multiplying the stadia reading by the square of cos A. There is no indicator.
The instrument is marked on the front: STADIA COMPUTER. The interior of the disc has DIRECTIONS FOR USE and a table providing the quantity to be added when a constant is used in measuring stadia. On the back, the rule is marked: 6675-664-4676 (/) CONTRACT NO. DSA 700-68-M-AF86 (/) FELSENTHAL INSTRUMENTS CO. (/) CHICAGO, ILLINOIS (/) 22040 (/) MFR'S PART NO. FAE-15. It has a blue plastic case with snaps and a holder for a label. This object was donated with a second, duplicate Felsenthal stadia computer, which was assigned the same catalog number.
The instrument resembles Cox's Stadia Computer (see 1987.0221.01 and 1987.0221.02). Donor Ben Rau dated the object to 1968, which is consistent with the form of the company name on the instrument. For Felsenthal company history, see 1977.1141.01 and 1977.1141.02.
References: Deborah J. Warner, “Browse by Maker: Felsenthal,” National Museum of American History Physical Sciences Collection: Navigation , http://americanhistory.si.edu/collections/navigation/maker.cfm?makerid=173; accession file.
Location
Currently not on view
date made
ca 1968
maker
Felsenthal Instrument Co.
ID Number
1977.1141.41
catalog number
336425
accession number
1977.1141
This 10-inch duplex slide rule is made from a magnesium alloy coated with white celluloid. It has a flat glass indicator with metal sides and stainless steel end posts. One screw on the back bottom side is missing.
Description
This 10-inch duplex slide rule is made from a magnesium alloy coated with white celluloid. It has a flat glass indicator with metal sides and stainless steel end posts. One screw on the back bottom side is missing. The top side is engraved with a serial number: CO24920.
The front of the rule has nine D scales, four also labeled 1/N, one also labeled Co, and four also labeled N. The two groups of four scales are extended and folded, so that for reading off logarithms, the rule is the equivalent of a rule 80" long. The slide has CF, CI, and C scales.
The slide has several markings above the scales. The first marking reads: INTERNATIONAL (/) COPYRIGHT 1947 (/) U.S.A. COPYRIGHT 1947 (/) R. C. PICKETT, A. F. ECKEL (/) CHICAGO, U.S.A. Second, there is a table for Digits or Zero for Sine and Tangent and a table for the number of digits in a result found on the C scale. Third, a logo inside an oval reads: DECI• (/) LOG LOG (/) Trade Mark. Fourth is another table for whether a result has zeroes or digits in results for squares, cubes, and roots. The fifth marking reads: THE NUMBER OF ZEROS IS (/) ONE LESS THAN THE ABSO- (/) LUTE VALUE OF THE NEGA- (/) TIVE CHARACTERISTIC. (/) EXAMPLE: 10-5 = .00001. The sixth marking reads: THE NUMBER OF DIGITS IS (/) ONE GREATER THAN THE (/) POSITIVE CHARACTERISTIC. (/) EXAMPLE: 105 = 100,000. Finally, a mark at the right end of the slide reads: PATENTS PENDING (/) MADE IN U.S.A. (/) PICKETT & ECKEL, INC. (/) CHICAGO 3, U.S.A. (/) MODEL 2.
The back of the rule has three cube root scales, an L scale, a D scale, and two square root scales. The scales for roots are folded, so that the rule is the equivalent of 60" in length for cube roots and 20" in length for square roots. The slide has two T scales and ST, S, CI, and C scales. The left side of the slide is marked: INTERNATIONAL (/) COPYRIGHT 1945 (/) U.S.A. COPYRIGHT 1945 (/) R.C. PICKETT, A. F. ECKEL (/) CHICAGO, U.S.A.
Arthur Frederick Eckel (1894–1960) and Roswell Colvert Pickett (1892–1969) partnered in Chicago in 1943 to manufacture slide rules. By 1946, they had transitioned from paper slide rules to magnesium, and Pickett established a branch of the company in Alhambra, Calif. In 1947, Maurice L. Hartung, a University of Chicago professor who helped Pickett & Eckel market their products to schools, described the Model 2 in How to Use the Deci-Log Log Slide Rule (Chicago: Pickett & Eckel, 1947). A copy of this pamphlet is 1979.0601.04. Eckel received four of the patents mentioned as "pending" on the object in 1948 and 1949. He left the company around that time, and his name was removed from slide rules by 1950. Thus, this example was probably made between 1946 and 1950.
Indeed, the donor, Frank M. Graves, reported that he used this rule as a college student. He received a Bachelor of Science degree in chemistry from Syracuse University in 1949.
The rule fits in a brown leather case marked on the flap with "Pickett" in script over a triangular logo. A belt loop on the back of the case is marked: SADDLE (/) LEATHER. The logo was used by the company from 1950 to 1958, so the case may be a replacement. The style of the belt loop, though, differs from the ring construction depicted in Pickett's 1953 catalog. In 1953, Model 2 and its case sold for $21.35.
References: Arthur F. Eckel, "Decimal Point Locator for Slide Rules" (U.S. Patent 2,446,696 issued August 10, 1948), "Calculator and Decimal Point Locator (U.S. Patent 2,466,883 issued April 12, 1949), "Slide Rule," (U.S. Patent 2,466,983 issued April 12, 1949), "Interchangeable Scale for Slide Rules" (U.S. Patent 2,491,650 issued December 20, 1949); Pickett All-Metal Slide Rules and "Retail Price List-Catalog," (Chicago: Pickett & Eckel, February 1, 1953); International Slide Rule Museum, "Pickett All-Metal Slide Rules," http://sliderulemuseum.com/SR_Dates.htm#Pickett; Accession File.
Location
Currently not on view
date made
1946-1950
maker
Pickett & Eckel, Incorporated
ID Number
1979.0601.02
catalog number
1979.0601.02
accession number
1979.0601
This clear plastic semicircular protractor is divided by tens and marked by hundreds from 100 to 3,100 mils and from 3,300 to 6,300 mils. Mils are units used in artillery and other military applications; 1,000 mils is equivalent to 56.25°. A pinhole is at the origin point.
Description
This clear plastic semicircular protractor is divided by tens and marked by hundreds from 100 to 3,100 mils and from 3,300 to 6,300 mils. Mils are units used in artillery and other military applications; 1,000 mils is equivalent to 56.25°. A pinhole is at the origin point. The bottom edge of the protractor is divided by hundreds and marked by five hundreds from 0 to 8,000 yards. A small vernier appears to the left of the scale, and the scale is labeled: 1/20,000.
The interior of the protractor has a semicircular opening with a groove parallel to the origin point. Below the opening is a maker's mark: 16 INCH (/) G. FELSENTHAL & SONS, INC. (/) -CHICAGO-. The letters U.S. are printed above the origin point. Donor Ben Rau, who worked for Felsenthal, dated the object to 1942. The form of the maker's name indicates it was probably manufactured for the U.S. Army in the 1950s.
This protractor is very similar to 1977.1141.11, although the scale for plotting the distance of fired artillery is in yards rather than in meters.
See also 1977.1141.01, 1977.1141.02, 1977.1141.03, 1977.1141.05, 1977.1141.08, 1977.1141.09, 1977.1141.10, 1977.1141.12, 1977.1141.19, 1977.1141.20, 1977.1141.21, 1977.1141.22, 1977.1141.23, 1977.1141.24, 1977.1141.30, and 1977.1141.39.
Location
Currently not on view
date attributed by donor
1942
date made
1950s
maker
G. Felsenthal & Sons, Inc.
ID Number
1977.1141.18
accession number
1977.1141
catalog number
336402
This white plastic chart was designed for the U.S. Army Signal Corps.
Description
This white plastic chart was designed for the U.S. Army Signal Corps. It is a nomogram for finding the range correction in yards of a weapon, by lining up the meteorological correction as a percentage of the range and the range.
On the left is a scale marked “Range Correction in Yds.” On the right is a scale marked “Percentage Meteorological Correction” and on the diagonal between the two is a scale marked “Range in Yds.” According to a label received with the object and stored in the accession file, the object was made in 1945.
The meteorological correction is found from the temperature and wind speed using a related chart called a “sound velocity corrector” (for an example, see 1977.1141.42) .
A mark on the object reads: Range Correction Chart PT-63/TSS-1.
For an explanation of the mathematical theory of this kind of nomogram, see Lipka. For a similar device used for another purpose, see 1985.0636.01.
References:
Joseph Lipka, Graphical and Mechanical Computation. Part I. Alignment Charts, New York: John Wiley & Sons, 1921, pp. 65–
67.
Accession file.
Location
Currently not on view
date made
1945
author
G. Felsenthal & Sons
ID Number
1977.1141.43
catalog number
336427
accession number
1977.1141
This plastic instrument with a metal pivot combines a straight edge, dividers, a course protractor, and a time-speed and drift computer. Instructions are given on it. The date, maker and model number are taken from the accession file.
Description
This plastic instrument with a metal pivot combines a straight edge, dividers, a course protractor, and a time-speed and drift computer. Instructions are given on it. The date, maker and model number are taken from the accession file. The collections include two examples.
Reference:
Accession file.
Location
Currently not on view
date made
1960
maker
Felsenthal Instrument Co.
ID Number
1977.1141.40
catalog number
336424
accession number
1977.1141
This clear plastic semicircular protractor is divided by tens and marked by hundreds from 100 to 3,100 mils and from 3,300 to 6,300 mils. Mils are units used in artillery and other military applications; 1,000 mils is equivalent to 56.25°. A pinhole is at the origin point.
Description
This clear plastic semicircular protractor is divided by tens and marked by hundreds from 100 to 3,100 mils and from 3,300 to 6,300 mils. Mils are units used in artillery and other military applications; 1,000 mils is equivalent to 56.25°. A pinhole is at the origin point. The bottom edge of the protractor is divided by hundreds and marked by thousands from 3,000 to 0. A vernier appears to the right of the scale. The scale is labeled: 1/25,000 METERS. Superimposed on the scale is a second scale, divided by two hundreds and marked (in red) by two thousands from 0 to 6,000. A vernier appears to the left of that scale, which is labeled (in red): 1/50,000 METERS.
The interior of the protractor has a relatively small semicircular opening with a groove parallel to the origin point. Below the opening is a maker's mark: 8 INCH (/) FELSENTHAL INSTRUMENTS CO. (/) CHICAGO (/) FAE-23A. The letters U.S. are printed above the origin point. Donor Ben Rau, who worked for Felsenthal, dated the object to 1951. The form of the signature indicates the protractor was probably manufactured for the U.S. Army in the 1960s.
This protractor is very similar to 1977.1141.11. See also 1977.1141.01, 1977.1141.02, 1977.1141.03, 1977.1141.05, 1977.1141.08, 1977.1141.09, 1977.1141.10, 1977.1141.18, 1977.1141.19, 1977.1141.20, 1977.1141.21, 1977.1141.22, 1977.1141.23, 1977.1141.24, 1977.1141.30, and 1977.1141.39.
Reference: Copyright Office, Library of Congress, "Books and Pamphlets," Catalog of Copyright Entries, 3rd ser., 16, part 1, no. 2 (1964): 1392.
Location
Currently not on view
date attributed by donor
1951
date made
1960s
maker
Felsenthal Instrument Co.
ID Number
1977.1141.12
accession number
1977.1141
catalog number
336396
This clear plastic semicircular protractor is divided by tens and marked by hundreds from 100 to 3,100 mils and from 3,300 to 6,300 mils. Mils are units used in artillery and other military applications; 1,000 mils is equivalent to 56.25°. A pinhole is at the origin point.
Description
This clear plastic semicircular protractor is divided by tens and marked by hundreds from 100 to 3,100 mils and from 3,300 to 6,300 mils. Mils are units used in artillery and other military applications; 1,000 mils is equivalent to 56.25°. A pinhole is at the origin point. The bottom edge of the protractor is divided by hundreds and marked by thousands from 7,000 to 0. A vernier appears to the right of the scale. The scale is labeled: 1/25,000. Superimposed on the scale is a second scale, divided by two hundreds and marked (in red) by two thousands from 0 to 14,000. A vernier appears to the left of that scale, which is labeled (in red): 1/50,000 YARDS.
The interior of the protractor has a semicircular opening with a groove parallel to the origin point. Below the opening is a maker's mark: 16 INCH (/) G. FELSENTHAL & SONS, INC. (/) -CHICAGO- (/) FAE-8. The letters U.S. are printed above the origin point. Donor Ben Rau dated the object to 1945, but the form of the signature indicates the protractor may not have been manufactured for the U.S. Army until the 1950s.
This protractor is very similar to 1977.1141.12, although the scale for plotting the distance of fired artillery is in yards rather than in meters. The red ink on this instrument is particularly vibrant. See also 1977.1141.01, 1977.1141.02, 1977.1141.03, 1977.1141.05, 1977.1141.08, 1977.1141.09, 1977.1141.10, 1977.1141.11, 1977.1141.18, 1977.1141.20, 1977.1141.21, 1977.1141.22, 1977.1141.23, 1977.1141.24, 1977.1141.30, and 1977.1141.39.
Reference: Deborah J. Warner, “Browse by Maker: Felsenthal,” National Museum of American History Physical Sciences Collection: Navigation, http://americanhistory.si.edu/collections/navigation/maker.cfm?makerid=173.
Location
Currently not on view
date attributed by donor
1945
date made
1950s
maker
G. Felsenthal & Sons, Inc.
ID Number
1977.1141.19
accession number
1977.1141
catalog number
336403

Our collection database is a work in progress. We may update this record based on further research and review. Learn more about our approach to sharing our collection online.

If you would like to know how you can use content on this page, see the Smithsonian's Terms of Use. If you need to request an image for publication or other use, please visit Rights and Reproductions.