This book is the largest scientific encyclopedia in human history written by one person. Ibn al -Nafis worked to write down his encyclopedia for many years, so he put its drafts to come in three hundred volumes, Ibn al -Nafees was eggs of only eighty, then he passed away while he was eighty years old, in the year 687 AH in Cairo, and Ibn Al -Nafis gave the volumes the eighties with his library, his house and money to the Mansouri Bimaristan in Cairo - Qalawun Hospital now - which Ibn Al -Nafees was supervisor as the largest Cairo hospital at the time and the workplace of "President of Egypt Doctors", which is the position that Ibn Al -Nafis occupied until his death. And he was aggressive of this encyclopedia because of his belief in its value.