CHAPTER SEVEN
There are, as everybody knows, many ways of measuring time: and right through the ages learned men have argued heatedly in favour of their different systems. Hipparchus of Rhodes sneered every time anybody mentioned Marinus of Tyre to him: and the views of Ahmed Ibn Abdallah of Baghdad gave Purbach and Regiomontanus the laugh of their lives. Purbach in his bluff way said the man must be a perfect ass: and when Regiomontanus, whose motto was Live and let live, urged that Ahmed Ibn was just a young fellow trying to get along and ought not to be treated too harshly, Purbach said Was that so? and Regiomontanus said Yes, that was so, and Purbach said that Regiomontanus made him sick.
Tycho Brahe measured time by means of altitudes, quadrants, azimuths, cross-staves, armillary sp
