Following the 1894 earthquake, the Ottoman government decided to provide a new housing for the imperial observatory, the Rasathane-i Amire. Sismological instruments were provided and a commission including Aristidis Coumbary Efendi (director of the observatory), Emile Lacoine (technical advisor), the architect Raimondo D’Aronco, G. Agamennone and an officer were appointed to undertake the construction. According to the daily newspaper Moniteur Ottoman, the observatory would be built in Üsküdar. It seems that eventually the gardens of the Silahhane, the armory at Maçka, was considered more appropriate for such a project. This paper will introduce the architectural projects of 1895 for the construction of a new observatory in Istanbul.