Harvard Project Physics teaching "astrolabe" (quadrant)
Date: 1962-1972
Inventory Number: 2006-1-0098
Classification: Quadrant
Dimensions:14.3 × 24.7 × 0.9 cm (5 5/8 × 9 3/4 × 3/8 in.)
Accessories: white folded paper listing contents and instructions
DescriptionThe main component of the quadrant (the so-called Astrolabe) is a white plastic, half-circle compass. The degree gradations on the circumference of the compass are marked in blue. Each end of the straight edge of the protractor is marked as 90 degrees, and the gradations decrease in tens until the two gradation sets meet at 0 in the center of the arc portion of the compass. Each degree increment is further divided in ten by short blue lines, with the central line slightly longer.
There is a clear plastic attachment on the surface of the protractor. One end is a small arrow that points directly to the degree markings on the circumference. It is attached to a large, metal washer. On the other side of the washer, the clear plastic attachment narrows to a point, forming a long, skinny triangle. At its point, it is attached to a smaller metal washer. The straight edge of the compass is attached to a blue plastic strip with three metal divots.
The quadrant also includes a long black string, used as a plumb line for vertical orientation (as plumb lines are taken to point to the Earth's center of gravity). The Astrolabe also includes a long rectangular metal attachment that can be used to attach the compass to a tripod. It can also be used manually.
Signedon the white protractor: [crossed-ovals logo] DAMON
Inscribedon the accompanying instruction sheet: Catalog Number 50037
FunctionThis so-called astrolabe, but more properly called a quadrant, was used by students to find their local latitude or the elevation of celestial bodies. In order to determine the local latitude, students measure the elevation of the North Star. The plumb line, when weighted, serves as the vertical reference and the protractor (when the straight edge is positioned perpendicular to the plumb line) measures the elevation of bodies above the horizontal.
Historical AttributesThis apparatus was designed to be used with Project Physics, a national physics curriculum developed in the 1960s. Project Physics materials included teaching aids, apparatus for student experiments, and books.
The Project Physics Course grew out of a Harvard University initiative to teach all students physics, not just those who would go on to careers in science. The course aimed to be a "humanistically oriented" introduction to "science at its best."
Damon Engineering produced and marketed a set of Project Physics laboratory equipment in coordination with the curricular work of Harvard physics professor Gerald Holton, California high school science teacher F. James Rutherford, and Harvard Graduate School of Education professor Fletcher G. Watson.
Primary SourcesThe Project Physics Collection of course books is archived online here.
Linda J. Greenhouse, "Gerald Holton: The Discovery That Scientists Are Also Philosophers Should Not Depend On Accidents," The Harvard Crimson, December 12, 1966; found online here.
ProvenanceScience Center Undergraduate Physics Lab, Harvard University