Silage silo, near modern-day Fu Yat Yuen [????-????]
The location of the marker is approximate, as the silo has disappeared under the Chi Fu Fa Yuen development.
It can be seen in this photo, just below half way up, to right of centre, a round sructure with a conical roof:
The silo can also be seen on this 1959 map of the area. I've marked it with the letter A.