Gelenbevi Ismail Efendi

Ismail Gelenbevi (born 1730, date of death unknown) was an Ottoman mathematician and professor at the Naval College in Istanbul, Turkey.

Born in 1730 in the town of Gelenbe near Manisa, he is known under the name "Gelenbevi" ( _en. "from Gelenbe"), which means "de Gelenbe" in French, and "von Gelenbe" in German. He studied in İstanbul where he rose through the Ottoman examination system to the rank of "Müderris" (professor) at the age of 33.

At the request of the Sadrazam or Grand Vizier Halil Hamit Pasha ("Paşa" in modern Turkish) (1782-1785), and of the Fleet Admiral Cezayirli Hasan Pasha, he was appointed to a professorship in mathematics at the Naval College in Kasımpaşa, on the Golden Horn, in Istanbul. He received an award from the Emperor Sultan Selim III for his very accurate balistic computations.

Ismail Gelenbevi published some thirty five scientific articles written in Turkish and Arabic. He is credited with the introduction of logarithms in Turkey.