This is a very early 1900s sepia real photo postcard of the famous 100-inch telescope at Mt. Wilson Observatory in California.
It is in excellent unsent condition with fairly crisp corners and no yellowing. It is 3 3/8" by 5 3/8". Manufacturer and photographer unstated.
We believe this is the first use of this particular photo on a postcard. This photo was used later by E C Knopp Co. to make a linen postcard.
(Inv Codes: RP 3011-L26)