Help with recognize an old watch

Hi, I recently find my grandmothers old watch and I decide to try to reveal all story of that watch. She wasnt first owner, and I would like if you can help me with finding a original owner name and watch history. Its old full gold IWC with nubmer 778496 on the case, number on movement I cant see and dont know is there and number exist. It have also some symbols but I cant tell what they are. On the back of the watch there is some family crest( I think that belong to first owner) and date 5.8.1922 so I think it was made around that time. I would realy appriciate if you can tell me something more. Thanks in advance..
https://pictub.club/image/szxJOC
https://pictub.club/image/szxUQj
https://pictub.club/image/szlhJL
https://pictub.club/image/szlOW5
https://pictub.club/image/szlj51

Very nice piece...