Building the Observatory
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A S Partridge
When the Zeiss arrived in many cases on the wharf, the Winstone family was very helpful. They cleared it all and brought it all into their store. They assumed complete responsibility for the fabrication and erection of the dome itself which came out in case from Germany. The copper outside sheeting (there were three layers of that) came out in rolls and the coppersmiths from Winstones fabricated it all. They had their head coppersmith there for six weeks and it was all free.
There were a lot of difficulties on the site because they struck a lot of water. The foundations sank over on the hall side. I had demanded that pier for the Zeiss must sit on bedrock and the Trust Board agreed. The engineer in charge said it was sheer nonsense, and wanted to put down a raft foundation at about 12 feet. As a result the job was held up for a month but finally they were forced to carry on to rock. Believe it or not they had to go down 40 feet. I got the DSIR up with their instruments for a full vibration check on the rock and it was very, very slight indeed.
For the pier a slab of concrete was laid down on the bedrock somewhere of the order of 3 feet deep by 6 feet square and on that they built hollow stone blocks up for about 12 feet. They filled this square with compacted sand and put another slab of concrete on the top of that; and then they went up again with another 12 feet of these sand compacted blocks and finally up with solid concrete. As far as we can determine the pier has not moved any measurable amount since the instrument was set on it.
The Zeiss telescope was assembled by Kurt Gottlieb of the Mt Stromolo staff, who was in New Zealand at the time.
A S Partridge
Everything was tuned to the date when the Governor General would open the Observatory. But the building was miles behind. So here was Gottlieb with all his cases of equipment, surrounded by builders and sawdust and cement dust and everything, he had to scrape away a corner where he could open the equipment up and put it together while they were still working in the dome.
I remember going up one day when he opened up the main mirror. The next day we were going to put it into place. When he went to lunch he put only the covering on it, not the lid and he came back to find that someone had pulled the paper back and rubbed their hand across the mirror. Well, he nearly went berserk. It did not scratch it, the oxide overlay coating had saved it but this is the sort of problem he experienced in putting that telescope together.
Then he found that there was no circuitry diagram at all for the electrical side. Things started to go haywire so we brought in professional electrical engineers. But when they tried to trace the wiring they were completely stumped. Finally we muddled through, we got the thing going and only then did the circuitry arrive.
T Rounthwaite
I was curator of instruments at the time the Zeiss was going together, and spent quite a few nights after he (Kurt Gottlieb ) had gone, in setting up the polar axis. Kurt brought over notes for taking circumpolar photographs and calculating from the drift, using a measuring microscope, just how many minutes you should move the instrument up or down.
I finally settled however, for using the highest power (1100 magnifications) and setting a star on the edge of the field and making sure it stayed on the edge of the field. And similarly if a star right above that tracks perfectly, then the telescope is north and south.
Not only was the telescope well aligned but it has stayed that way throughout thirty years of concentrated use.
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