Does anyone recall this old time travel novel?

[bomolub]

I read this in the late 1950s or early 1960s.

A man has to escape the present for some reason, so jumps in a time machine and heads for the renaissance. There he sets up as an inventor/sculptor/painter using his future knowledge. Eventually he meets a woman named Lisa and paints her picture. Finally at the end of the novel he figures out or announces: "I am Leonardo da Vinci."

I've been looking for this for years; can anyone help?

[K. Riehl]

It is Twice in Time by Manly Wade Wellman published May 1940 in Startling Stories.
It was reprinted in Wonder Story Annual 1951. And was "fixed up" as a novel in the Avalon science fiction series in 1957.

[ghost8772]

I wonder if Heinlein didn't borrow at least part of the idea for that one. The Door into Summer had a scientist mention one of his assistants named Leonard Vincent had disappeared with an equal mass (the machine worked by sending one mass forward in time, the equal mass backwards) 500ish years in time travel.

[bomolub]

Originally Posted by K. Riehl

It is Twice in Time by Manly Wade Wellman...

K, thank you so very much; I found the 1958 paperback cover art on line and that's it! Now to get a copy and see if it is any good 50 years later. As a youngster, I was of course quite impressed.

Originally Posted by ghost8772

I wonder if Heinlein didn't borrow at least part of the idea for that one. The Door into Summer...

Ghost, thanks for that aside. I read this Heinlein novel years ago but didn't remember that little snippet; very humorous!

[black1]

There was also a really cool little sci fi story where some people in the 20th century find a cave in Italy with a whole load of Mona Lisa paintings attached to a machine. One of the guys cranked the handle and you saw it was an early peep show film with the Mona Lisa winking and getting her boobs out. The other guy couldn't stand the damage to Leonardo's reputation so set light to the machine - great story!

[Urlik]

Originally Posted by black1

There was also a really cool little sci fi story where some people in the 20th century find a cave in Italy with a whole load of Mona Lisa paintings attached to a machine. One of the guys cranked the handle and you saw it was an early peep show film with the Mona Lisa winking and getting her boobs out. The other guy couldn't stand the damage to Leonardo's reputation so set light to the machine - great story!

I remember that story.
didn't it start with a collector buying The Mona Lisa and although his experts declared it to be the work of Leonardo, they also pointed out subtle differences between the poses in it and the more familiar one hanging in the Louvre?

at least it explained her enigmatic smile