My first "10-speed" bicycle was manufactured in France by Motobecane. I used it at the University of Texas in Austin around 1975. To the best of my recollection, it was a Mirage. I perused the internet and found images from the 1975 Motobecane catalog that I put together into an PDF file: 1975 Motobecane Catalog.
I do not remember much about the details of this bike. It was blue. I remember replacing the saddle with a much better one made by Avocado. I did not have a car at the time and it was my only means of transportation. This bike was stolen from the parking garage at the Castilian Dorm during the 1975-1976 University of Texas academic year. A reward of $10,000 is offered for its return.