MEMORANDA. [1st, Sun rises 8 h. 8 m.

Fig 76 Fig 77 P = Pole of the heavens Fig 77 drawn on the plane of the meridian, showing the circles of the upper hemisphere, as the would appear to the eye situated at a great distance due East of the sphere. NWSE (Fig 76) or the horizon

- appears as a st. line, NS being seen edgewise

The Meridian (NS - Fig 76) appears as semicircle NP22. The E. + W. Points are seen in one with the centre ENW - 50[?] [degrees] fr. the pole is the Celestial Equator

Prime Vertical - EZW passing thru the E.+W. pts (In Fig 77 EZW does not appear being one with CZ, a radius joining the centre Zenith.

When the observer is on the equator the celestial Equator + prime vertical coincide

Altitude is measure on a circle of altitude from the horizon AH = altitude of A

Parallels of altitude are circles parallel to the horizon

Zenith Distance (Co-Altitude) is the arc included between the zenith and celestial body - ZA

Declination is that portion of the Meridian between the Equator and the body - Reckoned N. or S. from the Equator A3 = [illegible] of "A" Declination and Terrestial Latitude correspond - that is a star in 28[degrees] N. Dec. passes every day vertically over all places in 28[degrees] N

Polar Distance is the arc of the Celestial Meridian between a Celestial body + the Pole When Lat. + Dec are same name the P.D is the complement of the [delta?] to 90[degrees] When Lat. + [delta?] are different names PD = [delta?] + 90[degrees]

Azimuth is the Angle at the Zenith contained between the Merid. of the place + the circle of altitude passing thru the body. L.PZA is azimuth of A. (In Geodetic Computations reckoned from South around to 20

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BC Archives, MS-0392 Box 1 Volume 4 / FRANK SWANNELL PAPERS / Diary and enclosures, 1915.