'Al-Mas udi for instance, reports such a story about Alexander.
Sea monsters prevented Alexander from building Alexandria. He took a wooden container in which a glass box was inserted, and dived it to the bottom of the sea. There he drew pictures of the devilish monsters he saw. He then had metal effigies of these animals made and set them up opposite the place where building was going on. When the monsters came out and saw the effigies, they fled. Alexander was thus able to complete the building of Alexadria.
It is a long story made up of nonsensical elements which are absurd for various reasons ...'(Khaldun lists some reasons)'... Furthermore, the jinn are not known to have specific forms and effigies. They are able to take on various forms …. All this throws suspicion upon the story.'