The answer will be found in Articles section - History of Wrist Chronographs Pt 1
Bonjorno Massimo e benvenuto!
Since you are a newcomer and likely will have trouble navigating around, here is a link to the article which Dean mentioned:
You will find your answer there, but you will also find many interesting and fascinating facts and photos about the history of Vacheron chronos.
Read both parts!
In addition the collection of articles will keep you busy for days exploring the many faceted world of Vacheron Constantin.
I hope that wasn't just a run-by-fruiting . Still waiting for pictures...
with a Mrs. Doubtfire reference. Eh, my little poppet?