Help With ID On French Stamps?

Hello all,

I'm hoping to get some info on these french stamps...thanks in advance!

The second two are postage due. The 10c brown is SC#J30 the 20c green is SC#J32. Both issued between 1893 and 1941, the 20c specifically 1906.
The first one the 50c bister brown is SC#123 issued 1900-1929. All French of course. Tres bon!

I'm sure our French and cancel experts can tell you something about the triangular cancel on the 20c postage due.

Can you make out any hint of a letter inside the triangle?

Triangle = Taxe = Postage Due (canceller of postage dues)

France generally a blank triangle
some have numbers but unusual.

thanks for your feedback guys!...you rock!

no, I can't make out a letter inside the triangle...I actually thought it was a "V" all this time until I saw Rod222's example!
I see the triangle, but can't make out much else.

Great information. Why was the triangle cancellation or overprint used on the postage due stamps? Most of what I have doesn't have the triangle on them and are canceled with a regular post mark. I have one stamp that has both a triangle and a regular post mark.

Here is what marcophilie.org has to say about the open triangles:
http://www.marcophilie.org/x/x-tri-i.html
[scroll down the left frame for the open triangle, and if you are at all interested in cancels, prepare to be lost in that site for a few hours]

I take it to mean that the triangle was found in different sizes and was used to cancel the postage due stamps.

Here is how I think this worked, though I'm always happy to be corrected.

The UPU required a "T" mark on short-paid international mail. You'll commonly see French covers with the "T" in a triangle. A postage-due stamp would be affixed, and then canceled when the recipient had paid the shortage. It would make sense to repeat the triangle shape in the cancel for the postage due stamp.

Again, if someone can flesh that out or correct it, have at it.