Records of Milne Seismograph No. 16, At Christchurch, From November, 1901.

Transactions and Proceedings of the Royal Society of New Zealand, Volume 34, 1901, Page 607

Records of Milne Seismograph No. 16, At Christchurch, From November, 1901. Latitude, 43° 31′ 50′ S.; longitude, 172° 38′ 09′ E. Time employed: 11 h. 30 m. east of Greenwich. Numbers 1, 2, … from November, 1901. Time: N.Z.S.T., as stated above. P.T., preliminary tremors less than 2 mm. complete amplitude; A.T., after-tremors less than 2 mm complete amplitude; B., E., beginning and end of vibrations not less than 2 mm.; Amp., full amplitude in millimetres; B.P., boom period; midnight, 0 h. or 24 h. Records were commenced on this instrument on the 19th November, 1901. The instrument is erected on a brick pillar standing on a concrete foundation sunk to a depth of about 4 ft. 6 in. The concrete is of the form of a truncated pyramid of square section, the length of whose side at the bottom is 4 ft. 6 in. and on the top 1 ft. 6 in., from which rises the square sectioned brick pillar referred to. The geological formation is an alluvial plain of considerable thickness, in which are several water-bearing strata. From these the people of Christchurch derive their artesian water. C. Coleridge Farr, Observer.