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Last block in place

Two tasks remain to complete the observatory foundation.

 

1) The crown, a 12 cm thick ring of reinforced concrete, will cap the top of the masonry. The crown serves two functions: it binds the structure together and it secures thirty-two bolts which hold the dome rotation ring's steel track in place.

 

2) Both exterior and interior walls must be plastered. This forms a barrier against moisture, and it looks nice to.