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The building across the road is the newly constructed Windsor House. A crowd has congregated in the alley between Windsor House and Exchange Building to view work that is being carried out. Not sure of the exact scene but a China Mail newspaper article as noted here on Page 17 informs the reader that there were problems in piling and excavation due to the presence of an underground stream. There was also a network of electricity and telephone cables, pipes and sewers in the lane adjoining the Exchange Building on the Des Voeux Road frontage.