The Second
Published, by Order of the Ministry of Agriculture and Fisheries,
Colonel Sir Charles Close, KBE, CB, CMG, FRS
Director-General of the Ordnance Survey, Southampton

[Companion volume to the '2GL Abstract' - Original Index]
Contents *
Introduction   4
I (AJW) History of the Ordnance Survey Levelling 7
II (AJW) Instruments 11
III (AJW) Methods of Observation 15
IV (HLPJ) Orthometric and Dynamic Corrections 19
V (AJW) Tidal Observations 24
VI (HLPJ) Mean Sea Level 30
VII (HLPJ) Effect of Meteorological Conditions on the level of the sea 35
VIII (HLPJ) The errors of levelling and the method of reduction 39
VIX (HLPJ) Reduction of the observations of the level net 55

PLATES (gallery)
I Diagram of network of 1st Geodetic Levelling.
II Diagram of network of 2nd Geodetic Levelling.
III Diagram of difference of level of old and new levelling
IV Diagram of Tidal Gauges, Liverpool
V Zeiss Level
VI Zeiss Level
VII Geodetic Staves
VIII Details of Geodetic Staves
IX Graduation of Geodetic Staves
X Fundamental Bench Mark
XI Flush Bracket
XII Dunbar Tidal Observatory
XIIa Newlyn Tidal Observatory
XIII Automatic Tide Gauge
XIV to XX Sea Level Curves [not scanned ...]
XXI to XLII Error Curves [not scanned ...]
XLIII to XLVI Reduction Equations [not scanned ...]

* The initials are those of the writers of the respective chapters:
AJW standing for Lieut.-Colonel A.J. Wolff, DSO, RE,
and HLPJ for Mr H.L.P. Jolly, MA