Measuring & Mapping

Vernier Compass

Where, how far, and how much? People have invented an astonishing array of devices to answer seemingly simple questions like these. Measuring and mapping objects in the Museum's collections include the instruments of the famous—Thomas Jefferson's thermometer and a pocket compass used by Meriwether Lewis and William Clark on their expedition across the American West. A timing device was part of the pioneering motion studies of Eadweard Muybridge in the late 1800s. Time measurement is represented in clocks from simple sundials to precise chronometers for mapping, surveying, and finding longitude. Everyday objects tell part of the story, too, from tape measures and electrical meters to more than 300 scales to measure food and drink. Maps of many kinds fill out the collections, from railroad surveys to star charts.

Alidade

This alidade consists of a cherry bar with folding brass sights located near either end and centered on one beveled edge. The other beveled edge is graduated to quarter inches. The U.S. Geological Survey transferred it to the Smithsonian in 1907.Currently not on view
Description
This alidade consists of a cherry bar with folding brass sights located near either end and centered on one beveled edge. The other beveled edge is graduated to quarter inches. The U.S. Geological Survey transferred it to the Smithsonian in 1907.
Location
Currently not on view
ID Number
PH.247915
catalog number
247915
accession number
47736

Aneroid Barometer

The face of this cylindrical instrument is marked “HOLOSTERIC BAROMETER / COMPENSATED.” The additional circle with the letters “HBPN” was the logo of Naudet & Cie., and probably represents the words: Holosteric Barometer Paul Naudet.
Description
The face of this cylindrical instrument is marked “HOLOSTERIC BAROMETER / COMPENSATED.” The additional circle with the letters “HBPN” was the logo of Naudet & Cie., and probably represents the words: Holosteric Barometer Paul Naudet. The firm was founded in Paris in 1860 by Paul Naudet, and used the term Holosteric to mean “without liquid." The scale around the edge of the silvered metallic dial extends from 28 to 31 inches of mercury and is graduated to hundredths of an inch. A blued needle indicates the present pressure; a brass needle indicates a previous observation.
The “U.S. Signal Service – 1101” inscription on the back of the case refers to the organization that became responsible for America’s national weather service in 1870. The U.S. Weather Bureau transferred this instrument to the Smithsonian in 1904.
Location
Currently not on view
date made
ca. 1870-1890
maker
Naudet & Cie.
ID Number
PH.230002
accession number
42625
catalog number
PH*230002
230002

Set of Charts, Evans' Arithmetical Study

Around 1900 many American educators advocated the use of objects in teaching mathematics and the sciences. R. O. Evans Company of Chicago published this set of twenty chromolithographed charts.
Description
Around 1900 many American educators advocated the use of objects in teaching mathematics and the sciences. R. O. Evans Company of Chicago published this set of twenty chromolithographed charts. They were designed to apply the object method “to the entire subject of practical arithmetic.” The title chart shows a man in classical garb holding a diagram of the Pythagorean theorem and a pair of dividers, expounding to a child. Other instruments displayed include a pencil, a drawing pen, a magnetic compass, several geometric models, a globe, a telescope, two set squares, an hourglass, and one of Evans’s charts.
Charts include extensive commentary for teachers. There are sheets entitled Counting and Writing Numbers, Reviews and Colors, Addition, Subtraction, Multiplication, and Division,. Other charts discuss Fractions, Weights and Measures, the Metric System, and Mensuration (one chart considers the measurement of flat surfaces, another one 3-dimensional solids). There also are charts on Business Methods (3 charts), Lumber and Timber Measure,Surveying, Percentage, Commercial and Legal Forms, and Book Keeping. A variety of objects are shown.
The paper, cloth-backed charts are held together at the top by a piece of fabric that is tacked to a wooden backing. This backing slides into an oak case decorated with machine-made molding and panels. A mark on the case reads: This is the (/) Property of (/) F. C. Adams (/) Hillsboro N. H. (/) May 28 - 1902 (/) Loaned to (/) Miss L. Hany (?) (/) Teacher School Dist. No. 17. F.C. Adams is probably Freeman C. Adams (1845-1913) of Hillsborough and Manchester, N.H. This suggests that this particular example of Evans’ Arithmetical Study was used by a woman who taught at a school in New Hampshire.
Location
Currently not on view
date made
1897
maker
R. O. Evans Company
ID Number
2009.0086.01
accession number
2009.0086
catalog number
2009.0086.01

Surveyor's Compass

This surveyor's compass may date from the third quarter of the 18th century. The bar holding the vertical sights is straight and narrow. The needle rim is graduated to single degrees, and numbered in quadrants from North and South. The face reads clockwise.
Description
This surveyor's compass may date from the third quarter of the 18th century. The bar holding the vertical sights is straight and narrow. The needle rim is graduated to single degrees, and numbered in quadrants from North and South. The face reads clockwise. And, with an extra needle and scales at North and South, the compass can serve as a clinometer for measuring angles of elevation.
Location
Currently not on view
ID Number
1980.0695.01
accession number
1980.0695
catalog number
1980.0695.01

Surveyor's Vernier Compass

Surveyor's vernier compass marked "Wm. J. Young Maker Philadelphia." William J. Young began using this particular signature around 1840, and began putting serial numbers on his instruments in the early 1850s. The variation arc on the north arm extends 27 degrees either way.
Description
Surveyor's vernier compass marked "Wm. J. Young Maker Philadelphia." William J. Young began using this particular signature around 1840, and began putting serial numbers on his instruments in the early 1850s. The variation arc on the north arm extends 27 degrees either way. The vernier is moved by rack and pinion located on the south arm and hidden under a brass plate, and reads to 5 minutes. There is a circular level vial on the south arm and an outkeeper on the north arm. The face is dark, and the needle ring was probably silvered originally.
This compass belonged to David Newton Ellis (1850-1926), the County Surveyor of Monroe County, West Virginia.
Ref.: D. J. Warner, "William J. Young. From Craft to Industry in a Skilled Trade," Pennsylvania History 52 (1985): 53-68.
Location
Currently not on view
maker
Young, William J.
ID Number
1981.0648.02
accession number
1981.0648
catalog number
1981.0648.02

Surveyor's Vernier Compass

This surveyor's vernier compass has an unusual and ornate face decorated with Masonic symbols. The variation arc on the north arm extends 10 degrees either way; the vernier is moved by rack and pinion, and reads to 10 minutes. A level vial is on the south arm. The "J.
Description
This surveyor's vernier compass has an unusual and ornate face decorated with Masonic symbols. The variation arc on the north arm extends 10 degrees either way; the vernier is moved by rack and pinion, and reads to 10 minutes. A level vial is on the south arm. The "J. SIMPSON BARDSTOWN KY" inscription refers to Jonathan Simpson (1787-1863) who was was working in Kentucky by 1820, and who advertised in the Bardstown newspaper, The Republican, on October 3, 1844: "I shall keep on hand a constant supply of SILVERWORK of my own manufacture-warranted to be as good as any manufactured in the United States, and at the Cincinnati prices. My necessities compel me to labour as much as ever I did. I have a few Surveying instruments on hand, which I will sell very low."
Location
Currently not on view
maker
Simpson, Jonathan
ID Number
PH.325686
catalog number
325686
accession number
257690

Graphometer

This graphometer is one of several objects from the Bureau of Education that the U. S. Department of Interior transferred to the Smithsonian Institution in 1910.
Description
This graphometer is one of several objects from the Bureau of Education that the U. S. Department of Interior transferred to the Smithsonian Institution in 1910. Active during the period 1876-1885, the Bureau of Education had organized exhibits for national and international exhibitions, and collected educational materials from around the world for display in its museum in Washington, D.C. The graphometer is of nickel-plated brass. Its semicircle arc is graduated every 30 minutes, and read by vernier scales at either end of the alidade to single minutes. The "Ed LUTZ Paris" inscription is that of Edouard Lutz, an optical and mathematical instrument maker who worked in Paris in the second half of the 19th century.
Location
Currently not on view
maker
Lutz, Edouard
ID Number
PH.261271
accession number
51116
catalog number
261271

Bubble Sextant

This instrument was developed for the Navy by the Aeronautical Instrument Section of the National Bureau of Standards in 1924, and produced by the Bausch & Lomb Optical Company. The instrument bears a plaque that reads “BUBBLE SEXTANT / U.S.
Description
This instrument was developed for the Navy by the Aeronautical Instrument Section of the National Bureau of Standards in 1924, and produced by the Bausch & Lomb Optical Company. The instrument bears a plaque that reads “BUBBLE SEXTANT / U.S. NAVY / BUREAU OF STANDARDS / MODEL NO. 2 / 1924 / NO. 4.” Phillip Van Horn Weems, who donated this example to the Smithsonian, noted that "Six sextants were made at the time for $250,000 each. Bausch & Lomb lost money on the deal but naturally recuperated on later orders and on later models. I drew this sextant from the storeroom in North Island, at the Naval Air Station, San Diego, and made numerous tests with it, along with Byrd, Lindbergh, Ellsworth, etc. etc."
Location
Currently not on view
user
Weems, Philip Van Horn
maker
Bausch & Lomb
ID Number
AF.59069-N
catalog number
59069-N
accession number
242229

Crosby Pair of Steam Engine Indicators, ca 1930

An engine indicator is an instrument for graphically recording the pressure versus piston displacement through an engine stroke cycle. Engineers use the resulting diagram to check the design and performance of the engine. Manufactured by Crosby Steam Gage & Valve Co.
Description
An engine indicator is an instrument for graphically recording the pressure versus piston displacement through an engine stroke cycle. Engineers use the resulting diagram to check the design and performance of the engine. Manufactured by Crosby Steam Gage & Valve Co. of Boston, Massachusetts, these steam engine indicators are enclosed in a wooden case. Each consists of a steel piston; an interchangeable external, helical wound spring; a large single recording drum with a spiral spring; and a brass stylus. The piston causes the stylus to rise and fall with pressure changes in the engine under measurement thereby directly recording the indicator’s output on the paper. Around the drum’s base is wound a cord that is attached to the connecting rod of the piston on the steam engine being measured. This causes the drum to rotate as the engine’s piston moves. An internal coil spring causes the cord to retract and the drum to counter rotate back to its original position as the connecting rod returns. The result is a steam pressure-volume diagram which is used to measure the efficiency and other attributes of the steam engine. These indicators enabled simultaneous measurement of both ends of a cylinder.
The introduction of the steam indicator in the late 1790s and early 1800s by James Watt and others had a great impact on the understanding of how the steam behaved inside the engine's cylinder and thereby enabled much more exacting and sophisticated designs. The devices also changed how the economics and efficiency of steam engines were portrayed and marketed. They helped the prospective owner of a machine better understand how much his fuel costs would be for a given amount of work performed. Measurement of fuel consumed and work delivered by the engine was begun by Watt, who in part justified the selling price of his engines on the amount of fuel cost the purchaser might save compared to an alternate engine. In the early days of steam power, the method to compare engine performance was based on a concept termed the engine’s “duty”. It originally was calculated as the number of pounds of water raised one foot high per one bushel of coal consumed. The duty method was open to criticism due to its inability to take into consideration finer points of efficiency in real world applications of engines . Accurate determination of fuel used in relation to work performed has been fundamental to the design and improvement of all steam-driven prime movers ever since Watt’s time. And, the steam indicators’ key contribution was the accurate measurements of performance while the engine was actually doing the work it was designed to do. These Crosby steam indicators represented over one hundred years of evolution and improvement of the devices.
Location
Currently not on view
date made
ca 1930
ID Number
MC.335062
catalog number
335062
accession number
314531

Bubble Sextant

Edwin A. Link, Jr. presented this bubble sextant, in a beautiful alligator case, to P. V. H. Weems. It is a standard A-12 with an attachment that enables the user to view the real horizon.
Description
Edwin A. Link, Jr. presented this bubble sextant, in a beautiful alligator case, to P. V. H. Weems. It is a standard A-12 with an attachment that enables the user to view the real horizon. Link applied for a patent on this feature in 1943.
Ref: Link Bubble Sextant (Octant) Model A-12 Handbook: Description, Operation, Use, Adjustment (Binghamton, N.Y.: Link Aviation Devices, Inc., 1943).
Edwin A. Link, Jr., "Navigation Instrument Including a Horizon Attachment," U.S. patent #2,395,559
Location
Currently not on view
user
Weems, Philip Van Horn
ID Number
AF.59061-N
catalog number
59061-N
accession number
242229

Hygrometer (replica)

This is a modern replica of the oat-beard hygrometer that was designed by the English natural philosopher Robert Hooke and illustrated in his Micrographia (London, 1665). The inscription reads "Eichner Fecit MCMLIX"Currently not on view
Description
This is a modern replica of the oat-beard hygrometer that was designed by the English natural philosopher Robert Hooke and illustrated in his Micrographia (London, 1665). The inscription reads "Eichner Fecit MCMLIX"
Location
Currently not on view
maker
Eichner, Laurits Christian
ID Number
PH.316858
accession number
228484
catalog number
316858

Liquid Compass

The Ritchie ledgers, now held by Ritchie Navigation, indicate that this compass was manufactured on August 11, 1877, and sold to T.S. & J.D. Negus, a New York firm that sold a variety of nautical and optical instruments. It later belonged to the U.S. Coast & Geodetic Survey.
Description
The Ritchie ledgers, now held by Ritchie Navigation, indicate that this compass was manufactured on August 11, 1877, and sold to T.S. & J.D. Negus, a New York firm that sold a variety of nautical and optical instruments. It later belonged to the U.S. Coast & Geodetic Survey. The inscriptions read "RITCHIE BOSTON U.S.A." and "PATENTED APL. 7. 1863. APL. 10, 1866. MAY 12, 1868. JULY 19, 1870" and "9786."
Ref: E. S. Ritchie & Sons, Ritchie’s Liquid Compasses and Nautical Instruments (ca. 1905).
Location
Currently not on view
date made
1877
maker
Ritchie
ID Number
PH.337138
catalog number
337138
accession number
1979.0361

Dumpy Level

The U. S. Coast and Geodetic Survey Precise Level "is constructed without regard to cost, extreme accuracy being the governing consideration.
Description
The U. S. Coast and Geodetic Survey Precise Level "is constructed without regard to cost, extreme accuracy being the governing consideration. This fact accounts for the seemingly high price, which is for the complete instrument, with two achromatic eye–pieces, graduated and chambered level–vial having a value of 2 seconds per division. Completed packed, with extra heavy tripod...$300." Thus wrote G. N. Saegmuller, proprietor of Fauth & Co., describing the Precise Level that had been developed by E. G. Fischer and his colleagues in the Instrument Division of the Coast and Geodetic Survey. This example, marked "FAUTH & CO. WASHN. D.C. 2239" was made between 1900, when the form was introduced, and 1905, when Fauth went out of business. It belonged to the University of Missouri at Columbia.
To minimize changes due to temperature variation, Fischer's team developed an iron–nickel alloy with a very low coefficient of expansion. They also placed the telescope tube within a slightly larger tube, and sealed the openings between the tubes with chamois leather collars. To minimize disruptions caused by changes in weight or pressure upon the ground, Fischer's team mounted the level above the telescope. A mirror, mounted above the level, reflects an image of the bubble into a tube at the left side of the telescope. Thus, while the surveyor's right eye looks through the telescope to the distant rod, his/her left eye can see both ends of the level vial.
The Fischer level was Fauth's third precise level. The first was similar to the instrument that Kern had shown at the 1876 Centennial Exhibition held in Philadelphia. The second, unveiled in 1879, was based on a design originating in Vienna, Austria, and developed in the Instrument Shop of the Coast and Geodetic Survey, which was then under Saegmuller's direction.
Ref: E. G. Fischer, "Description of Precise Levels Nos. 7 and 8," Report of the Director of the United States Coast and Geodetic Survey (1900), Appendix 6.
George N. Saegmuller, Descriptive Price–List of First–Class Engineering & Astronomical Instruments (Washington, D.C., 1903), pp. 60–61.
Randall Brooks and Heather Bajdik, "Precise Levels in Surveys of North America," Rittenhouse 10 (1996): 48–57.
Location
Currently not on view
maker
Fauth & Co.
ID Number
PH.333634
catalog number
333634
accession number
300659

Surveyor's Transit

Instrument with a "Kolesch & Co. New York. 1796" inscription. The firm termed it an Engineer's Transit, No. 7650. The horizontal circle is graduated every 20 minutes, and is read by opposite verniers with celluloid reflectors to 30 seconds.
Description
Instrument with a "Kolesch & Co. New York. 1796" inscription. The firm termed it an Engineer's Transit, No. 7650. The horizontal circle is graduated every 20 minutes, and is read by opposite verniers with celluloid reflectors to 30 seconds. There is a clamp and tangent to the telescope. New, it cost $160.
Heinrich Adolph Kolesch (1855-1903) was a German immigrant who began in business in 1885, taking over the firm that had been founded by E. & G. W. Blunt. Kolesch & Co. was still using the Blunt dividing engine in 1925. The firm was incorporated in New York State in 1904, and dissolved in 1947.
Ref: Kolesch & Co., Illustrated Catalogue and Price-List (New York, 1913), pp. 228-229 for this type of instrument, and pp. 195 and 198 for the history of the firm.
Location
Currently not on view
date made
after 1885
maker
Kolesch and Company
ID Number
1989.0409.01
accession number
1989.0409
catalog number
1989.0409.01

Sextant

This unsigned sextant belonged to Oberlin College, and may date from the time of the founding of that school in 1833. The frame is brass.
Description
This unsigned sextant belonged to Oberlin College, and may date from the time of the founding of that school in 1833. The frame is brass. The silvered scale is graduated every 15 minutes from -5° to +160° and read by vernier with tangent screw and swinging magnifier to single minutes of arc. One trade card in the box is that of Thomas Hemsley (either father or son) who were in business in London throughout the first half of the 19th century, offering a wide variety of instruments and other items for navigational use.
Ref: Gloria Clifton, Directory of British Scientific Instrument Makers 1550-1851 (London, 1995), p. 132.
Location
Currently not on view
date made
19th century
ID Number
1980.0075.02
accession number
1980.0075
catalog number
1980.0075.02

Geodetic Transit

This transit marked "USC&GS No. 18" was designed by E. G. Fischer, chief mechanician of the U. S. Coast and Geodetic Survey. It is one of two identical instruments that were built in the Survey's instrument shop in 1888–1889.
Description
This transit marked "USC&GS No. 18" was designed by E. G. Fischer, chief mechanician of the U. S. Coast and Geodetic Survey. It is one of two identical instruments that were built in the Survey's instrument shop in 1888–1889. They were said to be "the most complete and best constructed transits the Survey has ever had for longitude." They had about the same optical power as the transits that Troughton & Simms had made in the 1840s, but weighed substantially less. When packed in two boxes for transportation, each instrument weighed "only" about 350 pounds. John Clacey made the objective lenses, and Edward Kahler made the eyepieces.
G. N. Saegmuller, who offered an apparently identical instrument for $900, termed it a "Coast Survey Transit. No. 30" and noted that the Survey used instruments of this sort "for time observations only."
Ref: Edwin Smith, "A Description of Two New Portable Transit Instruments for Longitude Work," Report of the Superintendent of the U.S. Coast and Geodetic Survey for 1889 (Washington, D.C., 1890), Appendix No. 9.
G. N. Saegmuller, Descriptive Price–List of First–Class Engineering & Astronomical Instruments (Washington, D.C., 1903), p. 75.
Location
Currently not on view
ID Number
PH.316661.01
accession number
226636
catalog number
316661

Telescopic Alidade

The telescope of this instrument has stadia wires and a hanging level. The base has a level vial, a screw adjustment, and a vertical arc that extends 50 degrees either way and that is read by vernier to single minutes.
Description
The telescope of this instrument has stadia wires and a hanging level. The base has a level vial, a screw adjustment, and a vertical arc that extends 50 degrees either way and that is read by vernier to single minutes. There is also a plumbing arm for use on plane tables.
Albert Joseph Seligman (1859-1935) probably bought this alidade in the late 1870s, when he studied mining engineering at Freiberg, and he probably donated it to the Rensselaer Polytechnic Institute, his alma mater, around 1899, when he obtained a seat on the New York Stock Exchange. The signature reads "AUGUST LINGKE & CO FREIBERG IN SA NO 1315." A German silver tag on the wooden box reads "Albert J. Seligman New York."
Location
Currently not on view
maker
August Lingke & Co.
ID Number
2001.0300.03
accession number
2001.0300
catalog number
2001.0300.03

Surveyor's Vernier Compass

This compass is marked "T. R. RANDOLPH CINCINNATI. O." and "1234" and "PATENTED JUNE 24 '79." On June 24, 1879, Theodore F.
Description
This compass is marked "T. R. RANDOLPH CINCINNATI. O." and "1234" and "PATENTED JUNE 24 '79." On June 24, 1879, Theodore F. Randolph received a patent (#216,759) for a surveyor's compass with a telescope sight, in which the telescope and its supports can be detached from the compass. In this example (which is missing the telescope and its supports) the raised rim is silvered, and graduated to 30 minutes. The variation arc, which is located on the compass face, extends 25 degrees either way, and reads by double vernier to single minutes. The carrying case is marked "PATENTED NOV. 9, 1880," referring to Randolphs' patent (#234,331) for a seamless leather container of this sort. This instrument belonged to the University of Missouri at Columbia.
Ref: T. F. Randolph, Illustrated Catalogue and Price List (Cincinnati, 1892), p. 2.
Location
Currently not on view
maker
Randolph, Theodore F.
ID Number
PH.333647
catalog number
333647
accession number
300659

Geologist's Compass

This is an aluminum compass with brass sights that was designed for topographical work. The raised rim and beveled outer ring are graduated every degree and numbered every 10 degrees in quadrants from north and south.
Description
This is an aluminum compass with brass sights that was designed for topographical work. The raised rim and beveled outer ring are graduated every degree and numbered every 10 degrees in quadrants from north and south. The northeast quadrant of the face has a variation scale that extends 27 degrees one way and 43 degrees the other; this is graduated to degrees, and reads by folded vernier to 5 minutes. The southern half of the face is graduated to degrees, and equipped with a pendulum clinometer pivoted at the center. There are level vials on the SE and SW corners of the plate. The four beveled edges of the plate are graduated, one to inches and tenths, one to inches and eighths, and two as protractors. The back of the plate has a diagram showing the arrangement of township numbering. The signature reads "KEUFFEL & ESSER CO NEW YORK." Other marks read "U.S. INDIAN FOREST SERVICE. DEPT OF THE INTERIOR" and "1958." New, with ball joint and socket for mounting on a jacob staff, this compass cost $25. The University of Missouri at Columbia donated it to the Smithsonian.
Ref: Keuffel & Esser, Catalogue (New York, 1913), p. 420.
Location
Currently not on view
maker
Keuffel & Esser Co.
ID Number
PH.333652
catalog number
333652
accession number
300659

Solar Compass

This solar compass, one of the earliest instruments of its kind, is marked "Burts patent Made by Wm. J. Young Philada." It belonged to Artemas Curtis, a brother–in–law of the inventor, William Austin Burt. It was made by William J.
Description
This solar compass, one of the earliest instruments of its kind, is marked "Burts patent Made by Wm. J. Young Philada." It belonged to Artemas Curtis, a brother–in–law of the inventor, William Austin Burt. It was made by William J. Young in Philadelphia, probably in 1840, and it nicely illustrates the complex process of developing a successful instrument. Following Burt's instructions, Young produced an instrument in which the vernier for the variation arc was moved by hand. When that design proved inconvenient, a tangent screw was added to move the vernier–and this tangent screw covered the signature. This example is of that type. In later examples, the signature appears where it can be easily read.
Ref: John S. Burt, They Left Their Mark. A Biography of William Austin Burt (Rancho Cordova, Ca., 1985).
Location
Currently not on view
maker
Young, William J.
inventor
Burt, William A.
ID Number
PH.328793
catalog number
328793
accession number
277834

Brunton Pocket Transit

The Brunton Pocket Transit was said to be "the most convenient, compact and accurate pocket instrument made for preliminary surveying on the surface or underground." It has a folding sight at north.
Description
The Brunton Pocket Transit was said to be "the most convenient, compact and accurate pocket instrument made for preliminary surveying on the surface or underground." It has a folding sight at north. The lid of the instrument, hinged at south and provided with sight line and small hole, serves as the second sight. Since the lid is mirrored, the user can read the needle while sighting a distant object. The needle ring is graduated to degrees. The western half of the face is graduated in degrees, in quadrants from west, and provided with a clinometer with vernier that reads to 5 minutes. The sides of the case and lid are flat, and so the instrument can be set up vertically when used for vertical angles. This example is marked "D. W. BRUNTON'S PAT. SEPT. 18, 1894 APR. 14, 1914 WM. AINSWORTH & SONS SOLE MANUFACTURERS PAT. OCT. 2, 12. MAY 27. 13. DENVER, COLO. U. S. A. 14711." It was owned by the University of Missouri at Columbia, and was probably made between 1915 and 1919.
David W. Brunton (died 1927), a Canadian–born surveyor working in Colorado, invented this instrument after growing tired of carrying heavy equipment through the Rocky Mountains. He obtained his first patent (#526,021) in 1894, and subsequent patents in 1912 (#1,042,079), 1913 (#1,062,582), and 1914 (#1,092,822). The Wm. Ainsworth Co. of Denver began marketing these instruments in 1896, and by 1899 had sold more than 200 units. The firm became Wm. Ainsworth & Sons in 1905. The Brunton pocket transit remains in production today in Riverton, Wyoming.
Ref: Wm. Ainsworth & Sons, Catalog BX of Precision Engineering and Surveying Instruments (Colorado, 1908), p. 62.
Peter von Gitter, "The Brunton Pocket Transit, A One Hundred Year Old North American Invention," Earth Sciences History 14 (1995): 98–102.
Location
Currently not on view
maker
William Ainsworth and Sons
ID Number
PH.333641
catalog number
333641
accession number
300659

Persian Drah

This wooden rectangular rule is reported to be a Persian drah, or pic, a unit of length measure used in surveying and architecture. According to Russ Rowlett, the pic (or pik) was a traditional unit of distance in the Eastern Mediterranean and Near East.
Description
This wooden rectangular rule is reported to be a Persian drah, or pic, a unit of length measure used in surveying and architecture. According to Russ Rowlett, the pic (or pik) was a traditional unit of distance in the Eastern Mediterranean and Near East. An "arm" unit, like the ell, the pic varied considerably. A typical value was about 28 inches (71 centimeters). This example is divided on one side in pencil and on the other with carved notches. The divisions on the pencil side are at: 3.0, 6.3, 9.6, 12.7, 25.3, 28.3, 31.6, 37.8, 50.3, 53.4, 56.6, 59.8, and 62.7 cm. The divisions on the notched side are at: 12.5, 15.7, 18.8, 21.8, 25.0, 37.9, 41.0, 44.2, 47.1, 50.2, 56.2, 59.2, and 62.3 cm.
The pencil side is marked at the right end: teheran (/) dept of State. In 1892, the U.S. Department of State transferred this object to the Smithsonian.
Reference: Russ Rowlett, How Many? A Dictionary of Units of Measurement, July 11, 2005, http://www.unc.edu/~rowlett/units/index.html.
Location
Currently not on view
date made
19th century
ID Number
1979.0991.01
accession number
1979.0991
catalog number
166897

Graphometer

This graphometer, purchased in Paris ca. 1890 and probably made there as well, has a silvered semicircle that is graduated to 30 minutes, numbered clockwise and counterclockwise. It is read by verniers at either end of the alidade to single minutes.
Description
This graphometer, purchased in Paris ca. 1890 and probably made there as well, has a silvered semicircle that is graduated to 30 minutes, numbered clockwise and counterclockwise. It is read by verniers at either end of the alidade to single minutes. There is a level on the alidade.
Location
Currently not on view
owner
Engineering Societies' Library
ID Number
PH.319962
catalog number
319962
accession number
241593

Industrial Thermometer

This is a short-stem instrument designed for industrial use. The brass V-shaped case is marked “Tycos” at top, and “Taylor / Instrument / Co.” at bottom.
Description
This is a short-stem instrument designed for industrial use. The brass V-shaped case is marked “Tycos” at top, and “Taylor / Instrument / Co.” at bottom. The black housing around the mercury-in-glass thermometer with a milk glass tube has a scale from 32 to 240 degrees Fahrenheit, and is marked “Tycos / ROCHESTER / N.Y. U.S.A.”
Hohmann & Maurer had been making instruments of this sort since the mid-1880s, and continued doing so after being bought out by Taylor Bros. in 1896. This example was made after 1908 when the Taylor Instrument Co. introduced the Tycos trade mark and dropped the Hohmann & Maurer signature and trade mark. It came to the Smithsonian in 1923.
Location
Currently not on view
date made
ca 1923
maker
Taylor Instrument Co.
ID Number
PH.308162
catalog number
308162
accession number
70532

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.