I don't have much on 1937 and 1938 (yet) but by 1939 Vietto had indeed mounted a cage on the downtube. I'll post those pics tomorrow, but here's a sneak-peak!
http://www.birfield.com/
(click on pic for larger version)
Aldo Ross
Blue Ball, Ohio
> Aldo Ross wrote:
> >
> > Pic of the Day Special
> > How To Mount Your Cages
> > Pt.1 - 1934-1935
> >
> > All the discussion about mounting bottle cages for use with aluminum
bottles got me digging through the magazines for examples. Here are the
first 7 photos, showing riders at the Tour de France in 1934 and 1935. More
variety than I'd realized.
> >
> > http://www.birfield.com/
> >
> > Aldo Ross
> > Blue Ball, Ohio
>
>
> =======================
> Rene Vietto, no cages, 1935 TdF:
> http://www.birfield.com/
>
> Description: Rene Vietto wins the 6th stage of the 1935 TdF to
> Aix-Les-Bains. Vietto is one of the few riders who used no bottle cages
> that year, carrying bottles in rear pockets instead. From "Le Miroir des
> Sports" No.835, 13 July 1935.
> ========================
>
> Great stuff Aldo!!!
>
> Rene Vietto is credited with being the first to mount his bottle to the
> down tube. I've read that he also tried mounting his rear brake caliper
> to the front of the brake bridge and also mounting the rear caliper
> underneath the chain stay. Anyone else read this?
>
> Chuck Schmidt
> South Pasadena, Southern California
>
> .