Finally, I have discovered the purpose of the concrete house that beside Sai Wan Swimming Shed. It is one of the Tide Gauge House that built in Year 1926. In fact, there are two of this house. One was located in Kennedy town, the other was located in Shau Ki Wan (still searching the exact location).
With the help of the old topographic map, it shows the name of the house. Furthermore, I search the Public Works Department Annual Report Year 1925, 1926 and 1927 (Thanks David to post the report link). I have found something very interesting about the history of this Tide Gauge House.
In Year 1925, PWD had a Harbour Development plan, built two Automatic Self-recording Tide Gauges. The sites were chosen at the eastern and western entrance. The design and machines were running hot, just facing some minor difficulties about blasting process. Construction started on 24th Nov, 1925 and the contact time for completion was 3 months only (I don't think a construction project can be finished within several months even today!).
In Year 1926, PWD announced the selected site and the contractor's name, Messrs Fung Chicken (??) & Co! Sure, this contractor cannot finish the job and all works were un-completed after 4 months (March 1926). A new contractor involved and completed the work on 26th August, 1926. It meant this project had spent 8 months to be finished.
In Year 1927, the PWD reported new contractor handed over the House in a satisfactory condition. The maintenance period was ended on 9th June, 1927.
I am not good in accounting, could anyone help me to calculate the total expenditure to build these two Tide Gauge House?
The location of the Kennedy Town house is quite far from the coastline. The only instrument to measure the tide level is Mier syphon tide gauge. It is just pointing a long tube into the sea and measure the pressure different. The pressure difference will mechanically plot to a data sheet. Different mechanism when compare with floating tide gauge. If using floating tide gauge, the house must be built far from nature coastline, forward to deeper sea level.
I also notice there is a small flat platform on the sea shore, not far from the House. I think the platform was used to install a Tide Pole (just a guess).
Thanks!
Photos that show this Place
Comments
Re: Tide gauge house
Interesting discovery. Measuring and recording tides was important for shipping. In earlier days, the tide was measured by hand. Starting towards the end of the 19th century, automatic tide gauges were introduced and used. Early gauges used floats that moved (via string and pulley) an ink pen on a slowly rotating drum with paper on on top. Very likely a device was used that is shown on your Tide Gauge Equipment photo or in the photo below
I think this type was used as "blasting below low water" is mentioned in the 1925 contract. As the house stands on the shore, a connection to the sea is necessary. Possibly a canal or pipe was constructed between the sea and the house, and the iron cover might be a part of it.
Re: Tide gauge house
Thank You for your information.
I have found that the house was built far from the sea level. May be there are pipe below the structure foundation. I may visit there again to check it out!
Thanks Derek, it's good to…
Thanks Derek, it's good to know more about this building.
(I've moved your text from the Forum Post to this page to keep everything together.)
Operation of the tide gauges
Probably the tide gauges were operated by the Public Works Department. It looks as if the Hongkong Observatory was not responsible as they report the construction of tide gauge stations not earlier than the 1950s.
Different usage of tide gauge date
Yes, the PWD report has mentioned that the instrument is kept by Crown. I read a report which is written by Ir Prof Wyss YIM (Hong Kong's sea-level record), inside he has mentioned the tide gauge records by HK Observatory are from 1954 to 2015. He also mentions the oldest HK tide gauge was establish on the North Point coastal reclamation.
In HKO website, under title History of the Hong Kong Observatory, it mentions the first Director of the Observatory, Dr William Doberck, made the first self-recording instrumental tidal measurement in Victoria Harbour. The tidal records for the years 1887, 1888, and 1889 formed the basis for tide predictions for Hong Kong in the tide tables published by the Admiralty, UK since 1893.
This means the early tide gauge records are used by the Admiralty only. Therefore this Tide gauge house is managed by PWD is true! Tide gauge data for military use.
Thanks!
long term record of sealevel from tide gauages
Old tide gauge data is useful to construct long local history of sealevel. You might ask at the hong kong observatory about their oldest records. A brief look (link below) shows they only have tide gauge data back to 1950's, but it is possible they know of these older records.
https://www.hko.gov.hk/en/education/aviation-and-marine/marine/00505-on…
Approach HKO
HKO mentions: In the early years, the Observatory made use of instruments to observe tide in Tsimshatsui, Kowloon. The observations for 1887-1888 were used to make tide tables, but the tide observation based on instrument ended in 1890.
Two tide gauge houses were built in 1927, this really means the data is not used by HKO or public. And the tide gauge station location points for Kennedy Town and Shau Ki Wan have not shown on the station map by HKO.