This device probably appears in the background of street-view photographs of the location from that time.
‘EVA’ takes control- HK’s first automatic traffic lights.
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
Submitted by IDJ
Date picture taken (may be approximate):
Sunday, August 12, 1934
Gallery:
Connections:
- ‘EVA’ takes control- HK’s first automatic traffic lights. shows Place Junction of Des Voeux Road Central and Pedder Street [????- ]
Comments
Here's a view from 1941
Here's a view from 1941 showing the lights on a little island between the tram tracks:
EVA takes control
Well spotted!
Traffic light date
My guess was 1935 - so a near miss.
Where was the editor?
Interesting to see a typo having slipped through in the original print article: "The Hong Kong Tramways, Ltd., who, in connection with the who, in connection with the Electrical Department..."