The Roswell slides promoters seem to be obsessed with the idea that real researchers are all convinced that the "being" depicted in the Roswell slides is a mummy. Yes, that is a possibility that many have raised, but no-one has yet put that forward as a final conclusion (although I am still happy to take orders for my "It's a mummy, dummy" merchandise!).
So while no firm conclusion has yet been put forward publicly by the skeptics (as opposed to the promoters, who have positively asserted it to be a space alien from the supposed Roswell crash), could it have been a mummy? Is that prospect so far-fetched?
Well, no... as anyone who isn't a Roswell-is-aliens true believer (or a con man looking to soak money out of said true believers) would understand. Mummies were fairly common sideshow and carnival attractions back in the 1940s. For example, here is a newspaper article from the Hanover Evening Sun in late August, 1947, for a fair in Hannover, Pennsylvania (courtesy of Tim Printy):
Is this or something like it the Roswell slides being?
You'll have to wait until May 4th to find out for certain. But one thing is for sure - when the slides promoters tell you that it absolutely can't be a mummy, they clearly don't know very much about mummies, or history.