Sweeping
James Dunlop always looked at objects when they transited at their highest point in the sky and he had good eyes, he was only 32 years old. He used to sweep back and forth along the meridian and recorded the time, a description and the south polar distance when he found something. He also had to climb up and down a ladder because his 9 inch speculum mirrored scope was 9 foot long. He used candles for lighting, there were no red LEDS in 1826!
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