If you are a fan of whimsy, this fence may be exactly perfect for your yard. From Garden Drama,
I would recommend using new marbles. Vintage marbles will vary in size, slightly, so it you can deal with this, go ahead. So first, find your marbles if you’ve lost them, then determine a drill bit size that will bore a hole, ever so slightly smaller than your marble. You want it to press in snugly to help it stay put. No adhesive needed. I advise drilling test holes in scrap wood to help you get the right sized holes made. You made need to purchase a special sized bit.
Be prepared to invest in a lot of marble money!