It had various instruments such as a 4 metre wall quadrant made from copper and an azimuth quadrant which was the invention of Al-Tusi himself. Al-Tusi also designed other instruments for the Observatory which was far more than a centre for astronomy.

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it had various instruments such as a 4 metre wall quadrant made from copper and an azimuth quadrant which was the invention of al-tusi himself. al-tusi also designed other instruments for the observatory which was far more than a centre for astronomy.