Palmer's Computing Scale with Fuller's Time Telegraph, issue four
Date: 1847
Inventory Number: 5466
Classification: Slide Rule
Dimensions:1.1 × 28.6 × 28.6 cm (7/16 × 11 1/4 × 11 1/4 in.)
Accessories: cardboard envelope with fabric tie (from Harvard University Libraries); two additional Palmer's scales, see 5464 and 5465
DescriptionYellowed cardboard square, with red, gold-embossed cloth edges, joined at center by a metal fastener to two yellowed cardboard discs (one on either side). A flowered pattern is engraved in each of the square's four corners on both sides.
Printed on the face of the cardboard square around the circumference of the top disc is a logarithmic scale carrying values 1 to 10. A diamond, labeled "Mult. &Div.", is printed to the right of the 1 mark. Printed on the top disc around its circumference is a second logarithmic scale, also carrying values 1 to 10.
In total, fifty-seven gauge points on either of the two scales are labeled for different mathematical functions.
Two scales are printed on the back of the cardboard square around the circumference of the bottom disc. The outermost scale has values descending from 365 to 1 in a clockwise direction; the innermost scale has values ascending from 1 to 365 in a clockwise direction. A box surrounds the 365 mark on both scales. Every seventh value on the outermost scale is marked, "w. 1", "w. 2", "w. 3", and so on; the values in between are marked 1 through 6, in order. Approximately every thirtieth value is marked, "M. 1", "M. 2", "M. 3", etc. The value 10 on the outermost scale is concealed by a small metal pin.
Printed on the bottom disc around its circumference is a scale composed of the twelve months of the year in succession, graduated into days. Directions for the slide rule's use are printed above and below the center bolt.
This instrument, together with 5464 and 5466, is stored in a grey cardboard envelope with fabric tie from Harvard College Libraries. A Harvard College Library bookplate is affixed to the inside front cover the envelope; a pocket for circulation cards is attached to the back inside cover.
Signedface, top of top disc: Use the inner circle for Dollars, Cents & Mills, / or Pounds, Shillings & Pence. ;
face, top of top disc: Entered according to Act of Congress in year 1847 by J.E. Fuller In the Clerks office of the District Court of the United States for the Southern District of New York. ;
face, center of top disc: PALMER'S / COMPUTING SCALE. ;
face, center of top disc: IMPROVED BY / FULLER. ;
face, top disc, bottom center: Entered according to Act of Congress in year 1843 by Aaron Palmer in the Clerks Office of the District Court of the State of Massachusetts. / And by J.E. Fuller 1847. ;
face, top disc, bottom center: Engraved by George G. Smith 186 Washington St. Boston;
stamped over white paint on face, top disc, bottom center: HARVARD COLLEGE LIBRARY / GIFT OF / ESSEX INSTITUTE / SALEM / JAN. 17, 1922;
back, center of bottom disc: FULLER'S / TIME TELEGRAPH. ;
back, bottom disc, bottom center: Entered according to Act of Congress in year 1845 by John E. Fuller in the Clerks Office of the District Court of the State of Massachusetts ;
back, bottom disc, bottom center: Engd by G. G. Smith Boston;
on spine of cardboard envelope: Palmer's Computing Scale
Inscribedpencilled on back, top right: [crossed out, a library number] Math 7939.43;
pencilled on back, top left: [crossed out, a library number] QA / P3 ;
pencilled on back, bottom right: [illegible]
FunctionTwo early circular slide rules. Palmer's Computing Scale was used to solve mathematics problems, including multiplication, division, the calculation of interest, and geometry problems. Fuller's Time Telegraph was used to find the time, in either days or weeks, between two dates.
Primary SourcesFuller, John E. Improvement to Palmer's endless self-computing scale and key . . . . New York: John E. Fuller, 1846. Available online here.
ProvenanceOriginally owned by the Essex Institute in Salem, Massachusetts, this instrument was given to Harvard College on January 17, 1922. It resided in Widener Library, then the Cabot Science Library, before being transferred to the CHSI.
Related WorksFeazel, Bobby. "Palmer's Computing Scale." Journal of the Oughtred Society 3, no. 1 (March 1994): 9-17,
Feazel, Bobby. "Palmer's Computing Scale -- Revisited." Journal of the Oughtred Society 4, no. 1 (March 1995): 5-8.