In Chistchurch in the 1920s were the official daily weather summaries recorded by Self-recording Instruments.
If so it looks like they didn't use mercury thermometers as I believed.

From the press 1923.



"THE PRESS" WEATHER REPORT.

Readings by Self-recording Instruments at "The Press" Office, Christchurch up to 1 a.m. on May 10th, 1923.

THE WEATHER.

Meteorologioal observations taken at the Magnetic Observatory,
 Christchurch, at 9.30 a.m. and 5 .p.m. on May 9th: 9.30 a.m. 5 p.m.
 Barometer 28-943 39.853
 therniometer Dry bulb «48.1  50.6  Wet bulb ..48.1 60.3 Max. prev. 24 hours 62.5 Min. prev. 24 hours 46.S Max. in sun ..62 63 Min. on grass 4&5 Max. during day
 Humidity per cent. 100 98
 Wind S.W., N.K., T. light, v. light.
Cloud (0-10) 10 10 Bain ..0.845 0.020
http://paperspast.natlib.govt.nz/cgi-bin/paperspast?a=d&d=CHP19230510.1.14&e=-------10-CHP-271----0+weather+records-ARTICLE-