Dr. Yolanda Joradi and Dr. Hocine Benchina for their translation of Ahmed Almuradi’s Kitab-Ulasrar (Book of Secrets) which was written in the eleventh century (AD). It included his inventions and creations in engineering and mechanics illustrated with geometrical drawings and figures that are extremely complicated. This work shows one aspect of the contributions of Arab and Muslim scientists and their role in providing human life with inventions and machines which represented the pillars of modern scientific discoveries and developments. The translation is characterized by accuracy and clarity. Both translators have- meantime- authenticated and translated the original text as they managed to overcome the challenges of deformed pages of the origin. They inserted significant explanations and comments.