In irregular astigmatism the orientation of the
principal meridian changes from point to point across the pupil.
In 1815, two surveyors set out with stakes, chains, and compasses to establish Michigan Territory's baseline and
principal meridian, the standard coordinates by which townships and property descriptions would later be established.
After 'zeroing' the focimeter, the first step is to establish the power of the
principal meridian with the higher absolute back vertex power (BVP).
Peter Dorsher's study of Myers' nine myofascial meridians revealed that, 'In 8 of 9 comparisons, there was substantial overlap in the distributions of the anatomically derived myofascial meridians with those of the acupuncture
Principal Meridian distributions'.
is selected and attributed to the
principal meridian misalignment.
the axis varied +- 15-30o from 180
principal meridian, which is in agreement with other studies conducted on the refractive errors of children.
A piece of land is described as "the NW 1/4 of the SE 1/4 section 14, T 6 N, R 11 W, 6th Prin Mer." The translation is "the northwest quarter of the southeast quarter of section 14 in township 6 north and range 11 west of the 6th
Principal Meridian."
In previous work [14] each
principal meridian on the front surface of a cornea was independently aligned with the focused mires of a keratometer.
* The K-readings can be used to determine the radius of the steeper meridian, along with the use of axial edge tables to finalise the peripheral curves for each
principal meridian, or it may be possible to determine the fit from the fluorescein pattern
He is a charter member of the 6th
Principal Meridian Surveyors, vice president for Southern Colorado Professional Land Surveyors, a member of the Colorado Department of Transportation Survey Activities Committee (a group overseeing surveying within the department), project manager for the Statewide GPS Network, surveying instructor for the department, chair for Colorado Section - American Congress on Surveying and Mapping, and a member of the Civil Technology Advisory Committee for Trinidad State Junior College and the University of Southern Colorado.