Smithsonian - National Museum of American History, Behring Center

 
Physical Sciences Collection - Surveying and Geodesy

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Transit - click to enlarge

Transit - click to enlarge

Transit - click to enlarge

Click photos to enlarge.

Transit

Catalogue number:
PH*326958

Inscriptions:
"A. Megarey NEW YORK"

Dimensions:
height 11.25 inches; horizontal circle 7.5 inches diameter; needle 4.5 inches; telescope 12 inches long

Discussion:

Alexander Megarey (1790-1850) was born in Ireland and served an apprenticeship in London before moving to New York in the mid-1820s. In the 1840s he established a Navigation Warehouse, offering nautical charts and instruments, most of which were imported from England, and publishing a Nautical Almanac copied from that produced in London. He also ran a small shop for the manufacture of surveying instruments.

This transit, which probably dates from the 1840s, is similar to the ones that William J. Young was making at that time. The horizontal circle, located outside the compass box, is silvered, graduated to 30 minutes of arc, and read by two verniers to single minutes. There is one level vial on the upper plate at west, and another on the southern standard. The tangent screw that moves the plates is at east. The telescope is not centered, and transits only with the objective end down.

Further Information:

Transit
Young

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