Rare Pillar Transit - Wonderful Example

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This is a wonderful example of a rarely scene Pillar Transit. Bearing serial number 347, this Pillar Transit was likely made in the late 1860s. Pillar Transits were generally viewed as more accurate than a transit with normal standards.

I found a note in my dad's files about how surveyors used Pillar Transits:

"The type of work for which a pillar transit might be used was mostly laying out horizontal control for geographic surveys.  This were customarily performed by government surveyors, both military and civilian.  The work included both triangulation and field astronomy.  Field astronomy, however, would require a vertical circle which your instrument does not have.  All government surveys I am familiar with used instruments with A-shaped standards, not pillars.  Certainly a few could have been used by either government of private surveyors, but they would be in the great minority.

Pillar transits could also have been used for surveying long, straight boundaries of states or counties."

Another surveyor told me that Pillar Transits were also likely used for surveys involving bridges and tunnels.

Edmund Draper was born in Philadelphia in 1805 and died there in 1882. Draper went into business on his own in 1832: the Philadelphia City directories show as follows: 1833-37 Edmund Draper, instrument mf; 1837-38 Draper & Knox, Mathematical Instrument maker, Edmund Draper & Joseph Knox; 1852-82 Edmund Draper, mathematical & optical instrument maker.

This is a REALLY COOL transit. The only fault I see is that modern string is used to connect the pins holding down the telescope. I personally would remove the string, but I'll leave that decision to the next owner of this great instrument.

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